Most GPS units record your position every 2 seconds or so as a default, and then join those positions together in a line to work out your distance. Some allow you to change that recording interval to longer for battery saving or shorter for accuracy. Even if ignoring tree cover issues, the GPS is always going to effectively cut corners and give a shorter reading than a wheel based sensor. Think about your average twisty single track and how many corners you can get round in less than 2 seconds. Elevation accuracy with GPS is even worse than barometric. Loving your channel. Keep it up 👍
Once per second on Garmin units or at least that's what in the FIT file. Interesting idea that the GPS always cuts the corner. At once per second, the real question is how bad could it be? My back of the envelope calculations say it can't be too bad unless you're pulling greater than 1g turns (that's assuming the GPS is updating once a second and not blocked by trees, etc.)
I am a professional boat captain using GPS units a good deal more sophisticated than a bike GPS and I've seen altitudes recorded as 20' above sea level and 20' below sea level...I'll bet you can guess which of the two errors is more worrisome. As for linear measurement accuracy as already pointed out is really based upon periodic readings and straight line plots between those readings. It does not account for the over the ground distance traveled between them.
I think it’s important to load your tires with your typical ride weight and ensure your tire pressures are set as normal when measuring outer wheel circumference. The outer tread then compresses accurately to give a better true outer circumference reading, which is smaller than an unloaded tire. This smaller circumference turns faster, so your speed and distance will indicate faster, larger values. It would be interesting for you to use the automatic setup instead, and then compare your performance values. Good, informative video!
I second this. This should be especially important on a mtb since the tires can compress more then on a road bike under load. Doing an automated set-up while riding in a straight line with good gps-coverage would probably yield the most accurate result.
Thanks Clint for the information. I ride on open road no tree cover, but I definitely lose some mileage and elevation using gps. Especially evident on long rides. One example riding with buddy who also has Garmin computer but is using speed sensor from our last ride. My mileage was 160.4 miles with an elevation gain of 8,301 feet. He on the other hand logged 164.2 miles with 8,636 feet of elevation even though we rode the same route together. No tunnels or tree cover.
Great informative video. One thing to consider: Your wheel's circumference will always be marginally smaller when it's carrying a portion of your weight. Exactly how much smaller is very difficult to say and even varies as you ride.
Hey Clint. Quick suggestion. As you’ve seen in other comments there is some variability in circumference setup with MTB because of the lower pressures we use. I’ve found the best and easiest way to set it up is to use automatic and ride down an open straight road with full riding gear on. After a mile or two check to see what measurement automatic calculated. Set that number as your manual number. Quick, easy, accurate.
Mounting on the front tire will require less weight when measuring the circumference. I really didn't use this video to go into specifics on how to measure but I typically will put some weight on the front. But I can't imagine it making much of a difference.
sir, i saw a video of a guy mountain biking trail riding with his garmin device. the bumpiness of the trails and the cheapness of the garmin bike mounts allowed his garmin device to fall off on the trail. after about 2 hours of looking he found the device. i suggest to tether the device to your handlebars with your lanyard strap along with the mount for a double protection just in case the device falls off it wont go anywhere. its good to do with motor bikes too.
Been using these for a few years in conjunction with my 520 edge on MTB. They are more accurate than just GPS especially in woods / forest situations. When on gravel bike my speed sticks until tree cover is exposed to day light.
If you're riding with a Garmin GPS-enabled head unit and a Garmin speed sensor, how does Garmin deal with the two sets of input data during the ride (i.e., to show current speed)? Does it always default to the speed sensor and ignore the GPS signal for the purposes of calculating speed and distance?
The speed sensor is used over the GPS speed. I know this because when my speed sensor died during a ride, the GPS speed was quite laggy and not great under heavy trees. The speed under heavy canopy was showing nowhere near the speed I was actually travelling. I’d never seen that before with the combination of speed and GPS.
Nice video to incorporate all or most aspects of the speed and cadence sensor. I've been using them for 10 years and stumbled on this looking for battery changes and felt like a nice refresher. Thanks Clint
Thanks for talking about the difference in your distances w/o sensor. I have 100 or so rides on strava and I'm sure my mileage is not accurate.\ after watching this. My sneor pack arrives this week, cant wait to get it set up.
To attach the band of the cadence sensor I found that hooking it first on one side, then the other, and lastly shifting the center bit to fit its groove was the trick. (You'd think Garmin instead of the bureaucratic crappy instructions in their useless manuals would watch people attaching the thing and then figure out the instruction.) I've paired the cadence sensor twice but can't get it to read. There doesn't seem to be any How To Fix this. I'll go for a ride, maybe stop by the bike shop - and if they can't fix it... Congrats Garmin - Got me again. You'd think I'd learn after two worthless handheld GPS units. (Fragile screen, but the second one was so clever. Batteries lasted only 8 hours and were expensive, so instead of replacing a set before every single kayak paddle, I'd replace them on the water as needed. Absolutely calm seas, but the first step to replacing the batteries was remove the part that tethers it, second step was to pry open, with great difficulty, the battery door. Whoops right in the ocean - f me. Swore I'd never buy another Garmin device. At this point my advice is buy the cheapest speedo, timer, distance, cadence device you can find and use the map on your phone. Button button button button... I've got at least a dozen digital devices, I ain't got time to remember arcane multi step nonsense (besides if you do figure it out, you're not going to be doing so often that you'd remember it. Why is it that I can hop in a Tesla (and hand over a huge check) and immediately drive it home, but I'm already two hours into this stupid Edge 530 nonsense and it's not doing what it's supposed to??
My Garmin Edge 520 used in conjunction with a Garmin speed sensor began giving wildly inaccurate readings of speed such as 74mph. I have used in in the past”automatic wheel size” for years with no problems. I manually input the wheel circumference and this seems to have corrected the problem.
I went down this rabbit hole with my Wahoo bolt & speed sensor. I did a 50km 1/2 marathon event - my distance ended up being more like 60km. This is fine for your personal trails but in a long (for me) event all I really wanted to know is where I was in relation to water stations etc. As others have mentioned tyre deformation would account for over reading by a couple of percent (although maybe sticking it on the front tyre lessens this difference). I’d suggest testing your calibration on some well known straight/road segments.
Just a side note on the speed sensor I don't recommend pairing it to your phone because every time you ride the bike with out the garmin it will store the ride then upload it when it pairs with the phone because it stores the rides in the speed sensor. I love my speed sensor on my mtb I noticed a difference with distance too.
My battery for speed and cadence last around 2 years for my heart rate monitor (purchased same time as speed and cadence) has not needed replacement yet.
another good test....record the ride with 830/wheel sensor.....and at same time use the watch only w/o speed sensor. see what the difference is. (maybe strap the watch to the handle bars for a more consistent reading.) for distance.
Apologies if this comment is in here somewhere...I have multiple sensors on multiple bikes, and sometimes a neighbor rides one of my bikes with me. I have found that the sensors on the other bike get picked up on my Garmin computer. With only a number to identify multiple speed and cadence sensors, the readings get crossed...e.g. I see my cadence as 80 when I'm not pedaling because my friend is pedaling. I finally got down to it and named my sensors according to the bike they are on. Now when my computer "sees" the other sensors, I can reject the sensor based on the name, and not wonder if it is my bike's sensor or the other bike's sensor. Also, beware of accepting speed sensors as perfectly accurate. If the tire pressure is absolutely constant and the tire circumference measurement is dead on, then yes...but when the tire starts to lose air, the actual rollout will decrease and your mileage will read high. I wrestled with this for about a month and came to this conclusion after multiple rides with two gps (simultaneously) measuring against a wheel based measurement. Measurements were progressively higher (wheel size based) until checking tire pressure and inflating (from about 20 psi to 40 psi). Then the readings were instantly lower for the wheel based speed and distance. Tire pressure matters with wheel size based measurement but not with gps...just my findings...comments welcome. Cheers.
Could I use this sensor to measure the speed of any other rotating thing apart from bicycles? Can the manual wheel size be adjusted to literally any size?
I have used one of the older magnet style sensors to do this and it worked, I assume this would work with the newer style sensors too as long as it falls in the limits of the 4 figures allowed, 0001 to 9999
When you measure the tire circumference its supposed to be done with you sitting on the bike while rotating the wheel and with the same tire pressure you ride on the trail for best accuracy
@@ClintGibbs Yep that's how I used to do it :) Either way speed sensor will be far more accurate compared to not using one. Usually on the tight twisty trails my friends GPS will say 18km, while mine usually is around 26km, quite a big difference!
Nice video! I know where at least some of the difference between the distance of the speed sensor and the GPS track comes. Once I used to measure the wheel size like you did. But I found out that this isn't accurate since you have no real pressure on the handlebar like you did on an actual ride. Pressure on the handlebar will automatically decrease the wheel size by up to a few millimeters. What I tend to do from know on when I measure the wheel size is to lean my upper body a little bit over the handlebar so the wheel will get some pressure and decrease in size. Then I roll foreward and do the measuring.
WORD OF ADVICE TO GET A BETTER MANUAL WHEEL CIRCUMFERENCE READING YOU MUST BE SITTING ON THE BIKE SO THE TYRE COMPRESSES DOWN WHICH IS EXACTLY WHAT YOU DO WHEN RIDING. THE DISTANCE WILL BE DIFFERENT WHEN YOU SIT ON THE SADDLE WHILE MEASURING. OK.:-)..
So how about the cadence sensor I’ve connected the speed, but wondering how to connect the cadence is it automatically with the speed sensor? I don’t need to worry about it ?
I've been noticing that riding with trees around results in the speed often reading erroneously low only to jump up to like the right speed when there is a hole etc. Think I'll have to do this. Happens on tree lined roads.
Hi Clint, you have to put weight on front wheel. That should shorten your tire size to approx 2260mm. So accurate mileage should between 13 & 11.5 miles. (Proabably 12.2 is actual)
Hi Clint, nice vid, thank you for it. I'm thinking about buying Edge 130 plus, but I'm a bit concerned with its declared battery life of 12 hours, especially around 0°C conditions. I wonder if using with paired speed sensor improves its battery life? I can imagine, that in that case the device could pick GPS position less frequently. Any experience? Is it possible to charge the device from a power bank during the ride? Many thanks.
I haven't noticed the speed sensor improving the battery. In fact, the more sensors you look up. I think the less battery you get but it's not that noticeable. But I think the best option for you would get the Garmin external battery pack that you can attach to your 830. Perhaps you know about it, but if not, look into it. www.garmin.com/en-US/p/571552
Compressing the tire with rider weight changes the circumference, no? By how much, I have no idea. I've always let some air out of my tire when measuring circumference so I can physically push down and distort the casing while rolling it. That would be an interesting test to see how much difference, if any, it makes.
I agree with you. If you’re going to manually enter wheel size then I’d think tire compression would play a role. Some quick math shows that 2290mm rolling circumference equates to about 365mm radius. I’d guess rider weight would compress that 365mm down to something closer to 360mm, just ballpark. That new circumference based on 360mm comes to 2262mm, which is about 1.25% different than the 2290mm and that 1.25% should translate 1:1 over to the measured distance on rides. If you assume 10mm compression, then the difference amounts to 2.5%. Not a big difference-certainly not remotely big enough to account for the difference in his two ride length measurements-but not zero either. I think riding it around the neighborhood for 5min or so without tree cover would probably give you the most accurate estimate.
totally agree with you. truck tires have a spec listed as ''static loaded radius''... he is right about a gps not being as accurate though. the app probably takes every users's gps data and then uses it to acurately recreate the track so probably isnt very off for trails with many users
@@justingt3rs Oh ya, no doubt the GPS is off... probably much, much more off than any difference in the loaded/unloaded tire circumference. GPS makes bread crumbs trails to calculate distance, so the computer draws straight lines between the crumbs and omits corners. It also doesn't do very well with marginal elevation change (i.e. short rises and falls), which is extra distance covered. I just thought it was an interesting point to bring up; probably depends just how picky someone wants to be about accuracy.
@@cup_and_cone I crush up some blackboard chalk, wet it so it's like a paste then ride a straight line through it. I can usually see two Mark's on the asphalt corresponding to 2 rotations. Measure, ÷2 and I'm done.
Ha, I give you another interesting puzzle put speed sensors on both wheels and record the speed and distance. They won't be exactly the same. In a sharp corner, the back wheel cuts across and takes a shorter path than the front wheel. I remember riding around as a kid, going through puddles and making patterns with the wet bike tires. Path of the front tire was always longer than path of the back.
This might have been answered but I wanted to ask if using the speed sensor improves the garmin route directions, making them more accurate. e.g when to turn etc. I understand it makes the measured distance more accurate than the GPS in trees. Hope this make sense, thanks
It makes sense but I don’t think it’s really going to help. I believe that direction notifications and tracking are purely off of GPS. If Garmin has built in some kind of coordination with the speed sensor I do not know about it.
Does it matter where (how high up or down) on the crank arm the cadence sensor is mounted? Will mounting it closer to the pedal vs. closer to the bottom bracket yield different accuracy/readings?
I have the 830 with speed sensor as well. Battery in sensor is going on a year and a half! Thanks for the video! Just curious, which watch face was that on your Vivo?
I use a Garmin 510 with the speed sensor set to “automatic” on my Road Bike. When switching the 510 to my Mountain Bike, the 510 seamlessly goes to GPS. When switching back to my road bike, the 510 is 3-5minutes of riding to re-sinc and will not be accurate on reporting Garmin stats however STRAVA will correct the stats. My Mtb rides are in heavily wooded areas with lots of twisty track. The 510 reports the ride accurately (Garmin-STRAVA) when compared to others. Perhaps the location of the GPS satellites may affect the connection.
Great video! Clear and to the point. One question: how does the head unit “know” to get speed and distance data from the sensor rather than from the GPS? And is there any way to switch between GPS and speed-sensor input?
That's good question. I know in the FIT file there's a speed and a distance reading (once per second). Appears the distance is just the integral of the speed. My guess is that the Garmin unit overwrites the GPS speed with the sensor speed reading if it's connected. I have one on order and will be testing this out in the next couple of weeks.
I have one of these speed sensors now and from my use of it, the speed is taken from the speed sensor NOT the GPS if the sensor is connected (guess you could call it an overwrite). There's only one speed reading in the FIT file. Kind of disappointing. You could take the difference of the position and get an independent measure of the speed, but would have been nice if they had recorded both speeds.
I’ve been wanting to confirm this myself for months. I use the vivoactive 4 watch (like in the video) and am having trouble finding that type of riding data. Is it available on my watch somewhere?
Hi Clint. I just got a garmin speed and cadence sensor 2 and hooked it on my bike, everything works except the 3s powermeter as I don't have a powermetre. Can you tell me how to work it by just using the cadence and speed sensors? Thanks
@@robertpellegrino8947 it's one of the fields that you can select when you customize your screen. There is instant powe, 3 second power and 10 second power.
Do I need a garmin watch and the sensor or can I just use the speed sensor and the garmin connect app? Like if I don't care about my heart rate do I even need the watch? I just want to get more accurate miles
Will Garmin 510 recognize my old speed/cadence sensors from lixada wireless cyclocomputer (don't know if all wireless sensors use ant+ or not) or do I have to purchase a new sensor? Thanks
My friends and I debate this device accuracy all the time especially as it pertains to Strava KOMS. We've seen slower riders take KOMS as they roll in after the faster riders, sometimes even minutes after. People using iphone's take more KOMS than Android users and some Garmin users. Anyone else experienced this?
I have the cadence sensor and I just use the gps (garmin800) to record speed/distance when I go out for a ride. If I use the speed sensor, does it give better accuracy of speed and also distance?
Hi, Clint! I also have the 830. I use a cadence and a speed sensor on both, my road bike and Mtb. No issues on the road bike, but always loosing miles on the Mtb. Doing the Santos epic with others I have between 4-5+ miles less than everyone else. I’ve done exactly everything you did on this video. Is there an option where I can have my Edge830 record from the speed sensor and totally ignore the gps part??? Btw, this also happened with my old Edge520. Help!!! TIA!
My experience has seen that the speed sensor overrides the GPS data. Meaning, my rides are always longer and more accurate than most of my riding partners.
to be more accurate it have to be the right measures on the HUB, because thats where the sensor is sticking to and with a thicker hub it spins slower, so ihave the sensor kit but think i will not use it
Hi Clint, I used this speed sensor, the speed keep on got fluctuations around 0.5 sometimes, and sometimes like crazy, any fix to that, thx for replying
Just make sure it is paired and connected. You probably know this, but when it is connected you will see a little symbol on your Garmin letting you know. That's the first thing I would check
I've invested heavily in these new sensors as I ride a lot of different bikes. All of these fail after several months of use. I must have a dozen of them and none will pair anymore.
That's why I pushed down on the bars and put the same amount of weight I would have on the front tire as I would sitting on the bike. If I were measuring the rear wheel I would be sitting on the bike.
Sitting is a bit better but hard to do. Or you could just go for a ride and let the sensor calibrated itself after about a mile. Just make sure you do it on the open road that’s pretty straight.
I was recently gifted a set of these sensors. i do mountain biking and dont own a garmin watch nor a garmin bike computer. I have iphone and apple watch. would i be able to see my results after my ride with iphone or apple watch? And which app is best to use for them to work?
I have not used them with anything other than my Garmin computers, but this is what I found on their website support.garmin.com/en-US/?faq=lIHN1t3sLK02hr9jl36kyA
I have the Garmin speed/cadence sensor paired to my smartphone through garmin connect app. I want to use it indoors over the winter. Strava will not connect a speed sensor. Without using a Garmin computer or watch is there any way to hook up to a smart phone app?
Not really sure since I haven't tested it so I'll let others chime in here. But I'm pretty sure they will connect through the Zwift app if you ever choose to use a non-smart trainer with Zwift.
With sensor, your travel is longer. Then you measure it with no load, radius probably larger. With loaded tire can be different story. I am not sure what is auto. Maybe it averages by gps on a straight line.
Put a Garmen speed sencer on my trike. I know the wheel size is 24 inches and the setting the app I'm using is some metric figure that appears have something to do with distance per revolution.
Someone else is having some issue with cadence sensor and GPS auto start pause? I have a Polar V650 GPS for more than 2 years. None issue until i paired one Magene cadence sensor with it. Everytime i stop turning the cranck set, auto pause turns on, and the GPS stops to register, like if was not in movement. Just to confirm, the cadence sensor is correctly setted and Polar V650 GPS recognized it correctly like a cadence sensor. Is this a normal situation when using cadence sensor and GPS auto pause?
No, power meters are a completely different style of device, and much more expensive. Here's my review on the Garmin Rally power meter pedals: ruclips.net/video/d6BFG4uvTQc/видео.html
It was all going well until the mounting of that cadence sensor. If someone were using flat pedals then it wouldn't take long for that to be ripped off the crank by a shoe.
So from 13 mi/h before uploading to 12 mi/h after uploading…that is a huge difference…. I use kilometres and usually it deducts about 0.5 to 0.8 km/h from the original garmin reading. I am not sure what they do that and what algorithm they use to do that, because I know some cases in which the opposite happens and they gain up to 1 km/h even thought they were no exactly the fastest in the group
The wheel would be spinning at the same speed as you were riding before you left the ground. So I don't think it's going to cause an issue. But people who jump a lot probably aren't using a speed sensor.
Surprised you weren't already using speed sensor ----- I lose 10-20% of mileage on my local trails without one. Have put one on my gravel bike as well. My iphone with strava even records more mileage than my Garmin 520+ without the speed sensor. Most people gripe about strava shorting them miles ---- speed sensor is the solution imo.
Distance will be longer with the sensor. One reason is your wheel will turn faster when it got off the ground and adding more distance than the actual distance over ground.
You’re suggesting the wheel will increase speed when getting off the ground. That would be an interesting phenomenon. I can see that happen if you were to put it on the back wheel of a motorcycle and jumped through the air, but on the unpowered front wheel of a mtb? I don’t see that happening....
@@klaasa.deraad6355 If the jump was perfectly on the same plane you would be correct, but if you go down (or up somehow) any distance, the wheel will spin more than the actual horizontal distance traveled. Think of jumping 10 feet downwards straight off a cliff. The wheel will spin from the initial release counting as horizontal movement, but when you land you won't have actually traveled any horizontal distance because it was straight down. This will lead to an inaccuracy (albeit extremely minor).
You cannot do the wheel measurement that way. When you sit on the bike and add weight to the wheel, it compresses, and the measurement is off. Find a straight road on Google Maps, measure a distance between two known points (intersections), and then fiddle with the wheel diameter until it shows the same distance when you ride it. I can get my distance over a 10 km straight road accurate to within +/- 5 meters this way. But don't obsess too much over the accuracy, because it will change over time as your tire loses air, and be off again when you inflate it. :-)
Most GPS units record your position every 2 seconds or so as a default, and then join those positions together in a line to work out your distance. Some allow you to change that recording interval to longer for battery saving or shorter for accuracy.
Even if ignoring tree cover issues, the GPS is always going to effectively cut corners and give a shorter reading than a wheel based sensor. Think about your average twisty single track and how many corners you can get round in less than 2 seconds. Elevation accuracy with GPS is even worse than barometric.
Loving your channel. Keep it up 👍
Once per second on Garmin units or at least that's what in the FIT file. Interesting idea that the GPS always cuts the corner. At once per second, the real question is how bad could it be? My back of the envelope calculations say it can't be too bad unless you're pulling greater than 1g turns (that's assuming the GPS is updating once a second and not blocked by trees, etc.)
I am a professional boat captain using GPS units a good deal more sophisticated than a bike GPS and I've seen altitudes recorded as 20' above sea level and 20' below sea level...I'll bet you can guess which of the two errors is more worrisome. As for linear measurement accuracy as already pointed out is really based upon periodic readings and straight line plots between those readings. It does not account for the over the ground distance traveled between them.
I think it’s important to load your tires with your typical ride weight and ensure your tire pressures are set as normal when measuring outer wheel circumference. The outer tread then compresses accurately to give a better true outer circumference reading, which is smaller than an unloaded tire. This smaller circumference turns faster, so your speed and distance will indicate faster, larger values. It would be interesting for you to use the automatic setup instead, and then compare your performance values.
Good, informative video!
I second this. This should be especially important on a mtb since the tires can compress more then on a road bike under load. Doing an automated set-up while riding in a straight line with good gps-coverage would probably yield the most accurate result.
I just came on here to make this same comment. My own measurements with a 29x2.6 tire at 19 psi yielded a 31mm difference weighted vs unweighted.
Thanks Clint for the information. I ride on open road no tree cover, but I definitely lose some mileage and elevation using gps. Especially evident on long rides.
One example riding with buddy who also has Garmin computer but is using speed sensor from our last ride. My mileage was 160.4 miles with an elevation gain of 8,301 feet. He on the other hand logged 164.2 miles with 8,636 feet of elevation even though we rode the same route together. No tunnels or tree cover.
I find GPS not to be reliable. Wrong altitude etc, even using a Garmin.
Great informative video. One thing to consider: Your wheel's circumference will always be marginally smaller when it's carrying a portion of your weight. Exactly how much smaller is very difficult to say and even varies as you ride.
Hey Clint. Quick suggestion. As you’ve seen in other comments there is some variability in circumference setup with MTB because of the lower pressures we use. I’ve found the best and easiest way to set it up is to use automatic and ride down an open straight road with full riding gear on. After a mile or two check to see what measurement automatic calculated. Set that number as your manual number. Quick, easy, accurate.
Mounting on the front tire will require less weight when measuring the circumference. I really didn't use this video to go into specifics on how to measure but I typically will put some weight on the front. But I can't imagine it making much of a difference.
@@ClintGibbs 15% tire drop under weight is typical. 15% of 56mm tire is 8.4mm, or a 52mm difference in circumference, or about 2%, or about 0.25mph.
sir, i saw a video of a guy mountain biking trail riding with his garmin device. the bumpiness of the trails and the cheapness of the garmin bike mounts allowed his garmin device to fall off on the trail. after about 2 hours of looking he found the device. i suggest to tether the device to your handlebars with your lanyard strap along with the mount for a double protection just in case the device falls off it wont go anywhere. its good to do with motor bikes too.
I have a venu watch and am about to buy the speed sensor. Thank you for the video it makes life a lot easier than trying to follow a manual.
This is very helpful! I managed to get them both connected to my Vivoactive 3 in a matter of minutes. Can't wait to try them out!
Would be interesting to see the differing results on a road ride out of the trees.
not by much I suppose
Been using these for a few years in conjunction with my 520 edge on MTB. They are more accurate than just GPS especially in woods / forest situations. When on gravel bike my speed sticks until tree cover is exposed to day light.
5:58 that shock needs some love
Always enjoy your informative videos, Clint.
If you're riding with a Garmin GPS-enabled head unit and a Garmin speed sensor, how does Garmin deal with the two sets of input data during the ride (i.e., to show current speed)? Does it always default to the speed sensor and ignore the GPS signal for the purposes of calculating speed and distance?
The speed sensor is used over the GPS speed. I know this because when my speed sensor died during a ride, the GPS speed was quite laggy and not great under heavy trees.
The speed under heavy canopy was showing nowhere near the speed I was actually travelling.
I’d never seen that before with the combination of speed and GPS.
Nice video to incorporate all or most aspects of the speed and cadence sensor. I've been using them for 10 years and stumbled on this looking for battery changes and felt like a nice refresher. Thanks Clint
Garmin GPS will “compare” and verify the speed of the sensor after rolling 1 to 3 minutes.
Truth!! Good info and we’ll done with no fluff! If you want accurate mileage … wheel sensor Every time!
Thanks for talking about the difference in your distances w/o sensor. I have 100 or so rides on strava and I'm sure my mileage is not accurate.\ after watching this. My sneor pack arrives this week, cant wait to get it set up.
Long time follower of the Channel and Clint is the best. Ride safe Mate! :)
Wow, this video gives me an idea where I put it to my bike
To attach the band of the cadence sensor I found that hooking it first on one side, then the other, and lastly shifting the center bit to fit its groove was the trick. (You'd think Garmin instead of the bureaucratic crappy instructions in their useless manuals would watch people attaching the thing and then figure out the instruction.) I've paired the cadence sensor twice but can't get it to read. There doesn't seem to be any How To Fix this. I'll go for a ride, maybe stop by the bike shop - and if they can't fix it... Congrats Garmin - Got me again.
You'd think I'd learn after two worthless handheld GPS units. (Fragile screen, but the second one was so clever. Batteries lasted only 8 hours and were expensive, so instead of replacing a set before every single kayak paddle, I'd replace them on the water as needed. Absolutely calm seas, but the first step to replacing the batteries was remove the part that tethers it, second step was to pry open, with great difficulty, the battery door. Whoops right in the ocean - f me. Swore I'd never buy another Garmin device.
At this point my advice is buy the cheapest speedo, timer, distance, cadence device you can find and use the map on your phone. Button button button button... I've got at least a dozen digital devices, I ain't got time to remember arcane multi step nonsense (besides if you do figure it out, you're not going to be doing so often that you'd remember it. Why is it that I can hop in a Tesla (and hand over a huge check) and immediately drive it home, but I'm already two hours into this stupid Edge 530 nonsense and it's not doing what it's supposed to??
My Garmin Edge 520 used in conjunction with a Garmin speed sensor began giving wildly inaccurate readings of speed such as 74mph. I have used in in the past”automatic wheel size” for years with no problems. I manually input the wheel circumference and this seems to have corrected the problem.
I went down this rabbit hole with my Wahoo bolt & speed sensor. I did a 50km 1/2 marathon event - my distance ended up being more like 60km. This is fine for your personal trails but in a long (for me) event all I really wanted to know is where I was in relation to water stations etc. As others have mentioned tyre deformation would account for over reading by a couple of percent (although maybe sticking it on the front tyre lessens this difference).
I’d suggest testing your calibration on some well known straight/road segments.
I think I need to invest in more gadgets. Thanks for nice video!
Just a side note on the speed sensor I don't recommend pairing it to your phone because every time you ride the bike with out the garmin it will store the ride then upload it when it pairs with the phone because it stores the rides in the speed sensor. I love my speed sensor on my mtb I noticed a difference with distance too.
My battery for speed and cadence last around 2 years for my heart rate monitor (purchased same time as speed and cadence) has not needed replacement yet.
great review, thanks a lot
another good test....record the ride with 830/wheel sensor.....and at same time use the watch only w/o speed sensor. see what the difference is. (maybe strap the watch to the handle bars for a more consistent reading.) for distance.
Thank you Clint, this was so helpful 👍🏽
Excellent video, great info. TY
Really nice job on the review. Thank you.
Apologies if this comment is in here somewhere...I have multiple sensors on multiple bikes, and sometimes a neighbor rides one of my bikes with me. I have found that the sensors on the other bike get picked up on my Garmin computer. With only a number to identify multiple speed and cadence sensors, the readings get crossed...e.g. I see my cadence as 80 when I'm not pedaling because my friend is pedaling. I finally got down to it and named my sensors according to the bike they are on. Now when my computer "sees" the other sensors, I can reject the sensor based on the name, and not wonder if it is my bike's sensor or the other bike's sensor. Also, beware of accepting speed sensors as perfectly accurate. If the tire pressure is absolutely constant and the tire circumference measurement is dead on, then yes...but when the tire starts to lose air, the actual rollout will decrease and your mileage will read high. I wrestled with this for about a month and came to this conclusion after multiple rides with two gps (simultaneously) measuring against a wheel based measurement. Measurements were progressively higher (wheel size based) until checking tire pressure and inflating (from about 20 psi to 40 psi). Then the readings were instantly lower for the wheel based speed and distance. Tire pressure matters with wheel size based measurement but not with gps...just my findings...comments welcome. Cheers.
GPS comunicating with your garmin will correct the distance after 1 to 3 minutes of on the road cycling.
Could I use this sensor to measure the speed of any other rotating thing apart from bicycles? Can the manual wheel size be adjusted to literally any size?
I have used one of the older magnet style sensors to do this and it worked, I assume this would work with the newer style sensors too as long as it falls in the limits of the 4 figures allowed, 0001 to 9999
When you measure the tire circumference its supposed to be done with you sitting on the bike while rotating the wheel and with the same tire pressure you ride on the trail for best accuracy
Definitely true for the back wheel. With the front you can just put some pressure on the handlebars.
@@ClintGibbs Yep that's how I used to do it :) Either way speed sensor will be far more accurate compared to not using one. Usually on the tight twisty trails my friends GPS will say 18km, while mine usually is around 26km, quite a big difference!
Nice video!
I know where at least some of the difference between the distance of the speed sensor and the GPS track comes. Once I used to measure the wheel size like you did. But I found out that this isn't accurate since you have no real pressure on the handlebar like you did on an actual ride. Pressure on the handlebar will automatically decrease the wheel size by up to a few millimeters. What I tend to do from know on when I measure the wheel size is to lean my upper body a little bit over the handlebar so the wheel will get some pressure and decrease in size. Then I roll foreward and do the measuring.
thank you for this helpful video!
Nice ! Can you get power on garmin watch ? If so what sensor should you use ?
WORD OF ADVICE TO GET A BETTER MANUAL WHEEL CIRCUMFERENCE READING YOU MUST BE SITTING ON THE BIKE SO THE TYRE COMPRESSES DOWN WHICH IS EXACTLY WHAT YOU DO WHEN RIDING. THE DISTANCE WILL BE DIFFERENT WHEN YOU SIT ON THE SADDLE WHILE MEASURING. OK.:-)..
of course, but many do not realize this
Exactly, was a 5 cm difference for me! But then doing this makes you look slower and doing less miles 😅
Great video, thanks!
So how about the cadence sensor I’ve connected the speed, but wondering how to connect the cadence is it automatically with the speed sensor? I don’t need to worry about it ?
I've been noticing that riding with trees around results in the speed often reading erroneously low only to jump up to like the right speed when there is a hole etc. Think I'll have to do this. Happens on tree lined roads.
Howard Petrie I’m a roadie but have noticed the tree distortion too.
Great video
To be even more precise with the measurement of the wheel it should be done with you sitting on the bike to take tire deflection into consideration.
Does it make a difference which tire size you enter manually if you have two different size tires??
Hi Clint, you have to put weight on front wheel. That should shorten your tire size to approx 2260mm. So accurate mileage should between 13 & 11.5 miles. (Proabably 12.2 is actual)
Interesting observation. I will have to see if it makes a difference. Nice tip!
Hi Clint, nice vid, thank you for it. I'm thinking about buying Edge 130 plus, but I'm a bit concerned with its declared battery life of 12 hours, especially around 0°C conditions. I wonder if using with paired speed sensor improves its battery life? I can imagine, that in that case the device could pick GPS position less frequently. Any experience? Is it possible to charge the device from a power bank during the ride? Many thanks.
I haven't noticed the speed sensor improving the battery. In fact, the more sensors you look up. I think the less battery you get but it's not that noticeable. But I think the best option for you would get the Garmin external battery pack that you can attach to your 830. Perhaps you know about it, but if not, look into it.
www.garmin.com/en-US/p/571552
Compressing the tire with rider weight changes the circumference, no? By how much, I have no idea. I've always let some air out of my tire when measuring circumference so I can physically push down and distort the casing while rolling it. That would be an interesting test to see how much difference, if any, it makes.
I agree with you. If you’re going to manually enter wheel size then I’d think tire compression would play a role. Some quick math shows that 2290mm rolling circumference equates to about 365mm radius. I’d guess rider weight would compress that 365mm down to something closer to 360mm, just ballpark. That new circumference based on 360mm comes to 2262mm, which is about 1.25% different than the 2290mm and that 1.25% should translate 1:1 over to the measured distance on rides. If you assume 10mm compression, then the difference amounts to 2.5%. Not a big difference-certainly not remotely big enough to account for the difference in his two ride length measurements-but not zero either. I think riding it around the neighborhood for 5min or so without tree cover would probably give you the most accurate estimate.
totally agree with you. truck tires have a spec listed as ''static loaded radius''...
he is right about a gps not being as accurate though. the app probably takes every users's gps data and then uses it to acurately recreate the track so probably isnt very off for trails with many users
@@justingt3rs Oh ya, no doubt the GPS is off... probably much, much more off than any difference in the loaded/unloaded tire circumference. GPS makes bread crumbs trails to calculate distance, so the computer draws straight lines between the crumbs and omits corners. It also doesn't do very well with marginal elevation change (i.e. short rises and falls), which is extra distance covered. I just thought it was an interesting point to bring up; probably depends just how picky someone wants to be about accuracy.
@@cup_and_cone I crush up some blackboard chalk, wet it so it's like a paste then ride a straight line through it. I can usually see two Mark's on the asphalt corresponding to 2 rotations. Measure, ÷2 and I'm done.
Ha, I give you another interesting puzzle put speed sensors on both wheels and record the speed and distance. They won't be exactly the same. In a sharp corner, the back wheel cuts across and takes a shorter path than the front wheel. I remember riding around as a kid, going through puddles and making patterns with the wet bike tires. Path of the front tire was always longer than path of the back.
This might have been answered but I wanted to ask if using the speed sensor improves the garmin route directions, making them more accurate. e.g when to turn etc. I understand it makes the measured distance more accurate than the GPS in trees. Hope this make sense, thanks
It makes sense but I don’t think it’s really going to help. I believe that direction notifications and tracking are purely off of GPS. If Garmin has built in some kind of coordination with the speed sensor I do not know about it.
Hello!
Can we put the speed sensor on the pedal because the spinning bikes in gyms are not like regular bike.
That won’t works…it has to be on a rotating wheel.
Will the work with the Garmin Connect app.
Does it matter where (how high up or down) on the crank arm the cadence sensor is mounted? Will mounting it closer to the pedal vs. closer to the bottom bracket yield different accuracy/readings?
No, it does not matter
I have the 830 with speed sensor as well. Battery in sensor is going on a year and a half! Thanks for the video! Just curious, which watch face was that on your Vivo?
The name of the face is titanium.
I ordered this and bought a new Garmin too for 35o euro (for the Garmin alone)
I use a Garmin 510 with the speed sensor set to “automatic” on my Road Bike. When switching the 510 to my Mountain Bike, the 510 seamlessly goes to GPS. When switching back to my road bike, the 510 is 3-5minutes of riding to re-sinc and will not be accurate on reporting Garmin stats however STRAVA will correct the stats.
My Mtb rides are in heavily wooded areas with lots of twisty track. The 510 reports the ride accurately (Garmin-STRAVA) when compared to others. Perhaps the location of the GPS satellites may affect the connection.
Not exactly, the problem is edge 830 and 530 also and Sony GPS chip in them. You should check Garmin forum about that.
Could I pair these with my Apple Watch?
Can you load those coordinates up to like rouvy or bkool to create your own track.
Great video! Clear and to the point.
One question: how does the head unit “know” to get speed and distance data from the sensor rather than from the GPS? And is there any way to switch between GPS and speed-sensor input?
I guess it's magic. The GPS is still tracking you but it's using the speed sensor for your speed and distance. All in the programming I assume.
That's good question. I know in the FIT file there's a speed and a distance reading (once per second). Appears the distance is just the integral of the speed. My guess is that the Garmin unit overwrites the GPS speed with the sensor speed reading if it's connected. I have one on order and will be testing this out in the next couple of weeks.
I have one of these speed sensors now and from my use of it, the speed is taken from the speed sensor NOT the GPS if the sensor is connected (guess you could call it an overwrite). There's only one speed reading in the FIT file. Kind of disappointing. You could take the difference of the position and get an independent measure of the speed, but would have been nice if they had recorded both speeds.
I’ve been wanting to confirm this myself for months. I use the vivoactive 4 watch (like in the video) and am having trouble finding that type of riding data. Is it available on my watch somewhere?
Will it connect with samsing health app, though not sure if your using samsung phone
Hi Clint.
I just got a garmin speed and cadence sensor 2 and hooked it on my bike, everything works except the 3s powermeter as I don't have a powermetre. Can you tell me how to work it by just using the cadence and speed sensors? Thanks
You have to have a dedicated power meter to get power data. Is that what you're asking?
@@ClintGibbs ok if that's what I have. Can you tell me how to hook it up to the average 3s power in the garmin?
@@robertpellegrino8947 it's one of the fields that you can select when you customize your screen. There is instant powe, 3 second power and 10 second power.
Do I need a garmin watch and the sensor or can I just use the speed sensor and the garmin connect app? Like if I don't care about my heart rate do I even need the watch? I just want to get more accurate miles
You need a Garmin watch or a Garmin bike computer. The app itself does not track activities.
Will Garmin 510 recognize my old speed/cadence sensors from lixada wireless cyclocomputer (don't know if all wireless sensors use ant+ or not) or do I have to purchase a new sensor? Thanks
As far as I know it will work but I would see if you can contact Garmin customer service to make sure.
My friends and I debate this device accuracy all the time especially as it pertains to Strava KOMS. We've seen slower riders take KOMS as they roll in after the faster riders, sometimes even minutes after. People using iphone's take more KOMS than Android users and some Garmin users. Anyone else experienced this?
great video! do you get different times on your segments?
Times are the same, but average speed is of course higher.
I have the cadence sensor and I just use the gps (garmin800) to record speed/distance when I go out for a ride. If I use the speed sensor, does it give better accuracy of speed and also distance?
Yes, especially on twisty mountain bike trails. On the road it’s not as big of a difference.
may I know if I let the speed sensor detect wheel size automatically ,will it be accurate as put it manually?
Haven't tested that but I think it will be very close
We've come full circle...
Lol. True, and a great pun.
Hi, Clint! I also have the 830. I use a cadence and a speed sensor on both, my road bike and Mtb. No issues on the road bike, but always loosing miles on the Mtb. Doing the Santos epic with others I have between 4-5+ miles less than everyone else. I’ve done exactly everything you did on this video. Is there an option where I can have my Edge830 record from the speed sensor and totally ignore the gps part??? Btw, this also happened with my old Edge520. Help!!! TIA!
TBH I have not looked into turning off the GPS and only using the speed sensor.
My experience has seen that the speed sensor overrides the GPS data. Meaning, my rides are always longer and more accurate than most of my riding partners.
@@codybolick2368 unfortunately my Mtb rides are exactly the opposite
to be more accurate it have to be the right measures on the HUB, because thats where the sensor is sticking to and with a thicker hub it spins slower, so ihave the sensor kit but think i will not use it
Hi Clint, I used this speed sensor, the speed keep on got fluctuations around 0.5 sometimes, and sometimes like crazy, any fix to that, thx for replying
Just make sure it is paired and connected. You probably know this, but when it is connected you will see a little symbol on your Garmin letting you know. That's the first thing I would check
consumer grade gps isnt very good at accounting for changes in elevation when calculating speed and distance, esp bad for trail riding
Which model of Garmin computer are you using?
Fenix 7, Edge 840 and 1030
I've invested heavily in these new sensors as I ride a lot of different bikes. All of these fail after several months of use. I must have a dozen of them and none will pair anymore.
It is good to measure the circumference of the MTB wheel under load, otherwise an error occurs. 🚲
That's why I pushed down on the bars and put the same amount of weight I would have on the front tire as I would sitting on the bike. If I were measuring the rear wheel I would be sitting on the bike.
Should I seat on the or just push the bike in measurement?
Sitting is a bit better but hard to do. Or you could just go for a ride and let the sensor calibrated itself after about a mile. Just make sure you do it on the open road that’s pretty straight.
I was recently gifted a set of these sensors. i do mountain biking and dont own a garmin watch nor a garmin bike computer. I have iphone and apple watch. would i be able to see my results after my ride with iphone or apple watch? And which app is best to use for them to work?
I have not used them with anything other than my Garmin computers, but this is what I found on their website
support.garmin.com/en-US/?faq=lIHN1t3sLK02hr9jl36kyA
Thank you very much for this, I will try the wahoo app and I’ll update as to which one works.
It works great with the wahoo app, will have to get an additional hrm strap.
Hi good day, another question which other gps computer brand is compatible with garmin speed & cadence sensors 2?
Garmin sensors are fine. But their rubber band is the problem. How many did I lose those expensive sensors because of the weak rubber band?
I have the Garmin speed/cadence sensor paired to my smartphone through garmin connect app. I want to use it indoors over the winter. Strava will not connect a speed sensor. Without using a Garmin computer or watch is there any way to hook up to a smart phone app?
Not really sure since I haven't tested it so I'll let others chime in here. But I'm pretty sure they will connect through the Zwift app if you ever choose to use a non-smart trainer with Zwift.
@@ClintGibbs thank you, I will try that!
How can I put a wheel size of my spinning bike? The wheel have 17 inchs so what measure do I have to put?
The sensor has to go on the hub so it would obviously have to go on the rear wheel. If you can fit on a rear hub you should be OK.
With sensor, your travel is longer. Then you measure it with no load, radius probably larger. With loaded tire can be different story. I am not sure what is auto. Maybe it averages by gps on a straight line.
Will this work on any iOS app via the phone without the Garmin head unit?
I will defer to iOS users for this one. Curious myself…
Put a Garmen speed sencer on my trike. I know the wheel size is 24 inches and the setting the app I'm using is some metric figure that appears have something to do with distance per revolution.
Is that a RUclips award behind you on the wall?
Yep 😊
what if theres a small jump and the wheel is spinning airborne whould it count it as distance traveled?
Yes
Someone else is having some issue with cadence sensor and GPS auto start pause? I have a Polar V650 GPS for more than 2 years. None issue until i paired one Magene cadence sensor with it. Everytime i stop turning the cranck set, auto pause turns on, and the GPS stops to register, like if was not in movement. Just to confirm, the cadence sensor is correctly setted and Polar V650 GPS recognized it correctly like a cadence sensor. Is this a normal situation when using cadence sensor and GPS auto pause?
Can I use these sensors on an indoor Schwinn IC7 indoor bike?
Yes, you can use the sensors so that you can use a non-smart trainer on apps like Zwift
@@ClintGibbs not sure where i can put the speed one, what orientation should it be in order to work ok?
@@rosinegrean would have to go in the rear wheel, assuming it's the type of trainer where you keep the rear wheel on the bike.
By any chance what width tire are u using?
2.4 front and 2.2 rear
How did it do on reading your speed?
Perfect actually
Best to have the speed sensor on the rear wheel - otherwise a few wheelies is apt to give you a wrong reading.
Or get false reading from rear when locking up going into corners etc. either way it is better than basic phone gps
Working with Kinomap?
I have not tried it with Kinomap since I use a Wahoo Kickr. I’ll let someone else chime in for that.
Is this the same as a power meter! Garmin Connect app can't tell me my power curve bc I'm not using a power meter... Is this device the same thing??
No, power meters are a completely different style of device, and much more expensive. Here's my review on the Garmin Rally power meter pedals:
ruclips.net/video/d6BFG4uvTQc/видео.html
@@ClintGibbs okay... Did some reading today... So the power estimates i get from Strava are approximations...
@@SG-dg6oi yes, unless you have a power meter on your bike
@@ClintGibbs will a cadence and speed meter add more data to the Garmin connect app that's my last question thank you
@@SG-dg6oi yes, Garmin sensors, no matter what they are, will each collect more data.
E compatibile con il garmin 510 ?!
It was all going well until the mounting of that cadence sensor. If someone were using flat pedals then it wouldn't take long for that to be ripped off the crank by a shoe.
How much speed did Strava deducted from your actual garmin reading?….
About 1mph
So from 13 mi/h before uploading to 12 mi/h after uploading…that is a huge difference….
I use kilometres and usually it deducts about 0.5 to 0.8 km/h from the original garmin reading.
I am not sure what they do that and what algorithm they use to do that, because I know some cases in which the opposite happens and they gain up to 1 km/h even thought they were no exactly the fastest in the group
is this for the "Garmin Edge 130". Thanks in advance. :-)
Yes, this pairs with most edge computers, which includes the 130
when the 830 is a GPS cycling computer, why do we need a speed sensor?
That’s what I explain in the video at 6:30.
thanks for that review!
To calculate wheel size, just do (2*pi*radius).
When you make jumps the wheels spins many extra revolutions thus making the distance recorded further?
The wheel would be spinning at the same speed as you were riding before you left the ground. So I don't think it's going to cause an issue. But people who jump a lot probably aren't using a speed sensor.
Surprised you weren't already using speed sensor ----- I lose 10-20% of mileage on my local trails without one. Have put one on my gravel bike as well. My iphone with strava even records more mileage than my Garmin 520+ without the speed sensor. Most people gripe about strava shorting them miles ---- speed sensor is the solution imo.
I thought it was weird that my 1030 never asked for my wheel size, I guess it’s automatic only. 👍🏻
It is manual and automatic, I set it up manually.
Distance will be longer with the sensor. One reason is your wheel will turn faster when it got off the ground and adding more distance than the actual distance over ground.
You’re suggesting the wheel will increase speed when getting off the ground. That would be an interesting phenomenon. I can see that happen if you were to put it on the back wheel of a motorcycle and jumped through the air, but on the unpowered front wheel of a mtb? I don’t see that happening....
@@klaasa.deraad6355 If the jump was perfectly on the same plane you would be correct, but if you go down (or up somehow) any distance, the wheel will spin more than the actual horizontal distance traveled.
Think of jumping 10 feet downwards straight off a cliff. The wheel will spin from the initial release counting as horizontal movement, but when you land you won't have actually traveled any horizontal distance because it was straight down. This will lead to an inaccuracy (albeit extremely minor).
Does this work for wahoo computer..?
I'll let an owner of a Wahoo chime in but I think it does
You cannot do the wheel measurement that way. When you sit on the bike and add weight to the wheel, it compresses, and the measurement is off. Find a straight road on Google Maps, measure a distance between two known points (intersections), and then fiddle with the wheel diameter until it shows the same distance when you ride it. I can get my distance over a 10 km straight road accurate to within +/- 5 meters this way. But don't obsess too much over the accuracy, because it will change over time as your tire loses air, and be off again when you inflate it. :-)