New to mountain biking but also an engineer and have been obsessing over this topic since I started. It blew my mind how much different small changes in frame reach and stem length feel. For example a 440/50 feels like a completely different bike than a 455/35 frame/stem despite having identical effective reach of 490, which is something I tried while picking a frame size. My conclusion, for Trail/All Mountain an equal Stem/Offset is ideal. The bars move in the exact same path as the front tire making it incredibly intuitive and balanced. For XC/Climbing you want a stem longer than offset to get weight forward of the tire to keep it down. And for Downhill you want it behind offset to keep from having a tendency to rotate over the axle (OTB). By how much I do not have nearly enough experience or testing to say what those values are. But I think most people would be best served by something around +/- 5mm of offset, which way depending on what you typically do more of. This theory is reinforced by 40-50mm stems and 44mm offsets being the most common.
Well also remember that for XC, you want a fit more akin to a road bike to maximize wattage output and efficiency.. Look at Nino schurter etc... Their bikes are more like a tour road bike in terms of fit. I was a competitive road and track cyclist for years and the fit is much different than Enduro/downhill.. But your intuition is spot on..
@@TheMarkList Yeah XC was probably the wrong terminology for what I meant to say. It probably would have been more accurate to say for Technical Climbing or something akin to that. It’s amazing how something as simple as a bike can become such a complex engineering problem around geometry. I’ve done a little bit with race car suspension design, and it’s not that dissimilar, just a different application. Enjoyed your video though, good exploration of the topic not many people talk about.
@@sethrich5998 suspension is such a cool thing to dive into.. on any type of vehicle.. I'm a big fan of telemetry and data... it beats guessing or "feel" ... glad you enjoyed the video, but yes, technical climbing versus downhill, totally different applications and setup
@@TheMarkList Oh definitely. Yeah we did instrumentation and data acquisition on our prototype suspension for design iteration and for race setup. It was with the Formula SAE team at my college if you’ve heard of that.
"The bars move in the exact same path as the front tire" Except only the center of the bars moves the same as the front wheel. Your hands are out at the ends, and not at the same offset due to backsweep, do not move at all like the front wheel. And a really important aspect of the front wheel is the contact patch, and its relation to the steering axis, and your hands, changes with head tube angle, so matching stem to offset is going to be valid for some head tube angles. It's more about trying different stem lengths than about matching lengths.
I'm running a 35mm Spank stem, w/ a 60mm rise Spank handlebar, on a 44mm fork offset, all on a bike with a 455mm reach. I've messed around with various stem and bar combos, and this weirdo setup actually feels great. A more upright stance, allows me to really push hard into corners to load the front, yet not feel like I'm over the front when launching into the steeps.
I bought my first new eMTB there. I've just put a Funns Equalizer V2 stem (42mm, 35mm thicker bar the new one) on my Fox 38s 27.5in, and I'm loving it. It's spot-on for me. The 35mm was just too short, and the 50mm standard was just too far over the front, putting a lot of weight down on the forks. I'm 5'9" on a 20in large frame Cube Stereo 2024 Action Team 160. With Burgtec Ride High 38s cut to 780mm with those Peaty's Monarch grips, oh, it's nice now! It feels more responsive and stable, and it's just unbelievable for climbing! It took a few tries, but I got there!
5'9" on a 480mm reach bike is pretty wild. If all you are climbing is fire road and only doing DH runs then cool. For anything else, you have fallen into the trap of longer=better. Obviously body proportions play into sizing but 480mm is a LONG bike.
From a 35mm lenght to a 50mm Deity cooperhead made a HUGE difference, more relaxed, better fit, good tracking and cornering. The bike is alive, pop better at any needed situations and great at full speed. That does work superbly for me.
Just ordered 50mm high rise bars for a . more upright moto feeling I got a 2024 polygon xtrada 7 hardtail the stems low as it is but the factory bars are maybe 10mm rise I'm so leaned over great for climbing but sucks for long rides
The video I have been waiting for. I ride a 2020 Jeffsy, my first upgrade was swapping m1900 to stans flow ex3 with hopes. Not sure why the steering went heavier, but just decided in spring to use my premium Pike ultimate 51 offset over 42 yari, also upfork to 160 on a 150mm stem. I'm not so OTB now, but funny I didn't think I was that heavy over the bar at 150mm lol. Steering is lighter now than out of the box, quicker response, and already better cornering. I'm going to keep an 800mm bar for now. Oh, and less pedal strikes now. I was never worried about upforking, but that 9 degree difference did.
@@koretell I'm on 780 bars, usually run 770 and I have a huge wingspan... I think a lot of people ride too wide. Good to see you are experimenting with your setups. It takes a lot of time and patience and sometimes money to get it right! Thanks for the comment and for watching. Appreciate it!
I found this video, and am actually shocked. I messed around with stem length because of back pain, and I run a 50mm on my 51 offset fork, and a 40mm on my 44 offset fork, and when I did the 40mm on the 44 I had replaced the 50mm with it… stumbled across way better handling on accident really. Then I wanted to try the 50mm on place of old 70mm length stem just outta curiosity. Never understood why both bikes got so much better with handling, and this video matches my findings, and gives me some reasoning on what’s happening in my case as well. Thanks man! 🎉
I jist started the process of buying components to build up a frame. I'll have to check this out and see how it works for me. Thanks for the video on this subject!
I loved the ergonomics on my hard tail (long and low ) and really struggled to get on with my full suspension trail bike. After changing forks ,bars and stems I settled on a 60mm stem ,bars rotated max forward. This over the front body position by far suits me best as I ride trials sections for fun also. It’s also helped curb my poor front wheel high jumping technique. I honestly could not ride a high short stem. On aside note, I find the more you hang off the rear of the bike the more you are a passenger especially in the air. Chin over the stem almost always gives more control, I find anyhow.
2020 Hightower medium. I’ve run a 35mm stem and the bike felt way too short. Went back to 50mm and it’s been perfect. The bike was alway washing out the front tire with the 35.
Fantastic video! Provides me with some knowledge to make better decisions in my build out. Also, Mammoth? I assume you know my sister and brother-in-law, Rob and Cheryl Witherill.
@@RickCoreyRealEstate I do not know them.. I ride downhill and mostly pretty technical terrain and I'm usually the only one I see on the trail... And glad you got some value from the video!
A real experiment would be to get the 37mm lowers for your fork. Then swap between your current 44mm offset and the 37mm offset and see if the bike feels more or less balanced with matching stem lengths. If you feel more comfortable with a shorter stem on a shorter offset and a longer stem on a longer offset then you’ll know whether there is a correlation between offset and stem length.
I've matched offsets on my dh bike and now on the Kenevo Sl and on both it's been pretty great...frame reach will be something interesting to look at too... Am I on a small bike or one on the larger side ? But great way to look at data and to see if results compare! Thanks for the great response!
I ride a Merida with a 51mm fork offset. It came with a 40mm offset, and I can't even count the number of times I washed out the front end and crashed. After trying different stem lengths, I settled on a PNW 50mm stem. Since then, my bike hasn't washed out once, and I feel a whole lot more confident.
Been playing with stem length, stem spacer, different bar sweep and rise, and I’m now settled wit 35mm stem and 40mm rise bar. What I could say about all these years of experiments is bar roll and your muscle dominance. If you hv stronger lower body as in stronger hip and legs you will be more leaning forward liking shorter front end and higher rise bar. If you hv stronger upper body then it’s the opposite
I think it depends on the bike geometry as well , a 35mm stem felt great on my old bike , a hardtail with a 63.5 degree head angle and a 51mm offset . My new bike is a full suspension with a 65 degree head angle and 51mm offset . The 35mm stem felt too short with too much weight on the rear and a 50mm stem felt better but the front end felt floppy if that makes sense . So i went with a 43mm stem and it felt perfect .
@@justgo4033 yeah it depends on a lot of things. Type of bike you are riding, geometry, Terrain etc. In terms of Enduro and downhill and riding steep technical terrain, I think it's the sweet spot. I know I'm not the only one who keeps going back to this school of thought. I've tried just about every length and where it puts you over the front axle. Plus, everyones riding style and body proportions are different... So go with what's comfy and fast! Happy new year!
@ I found a good deal on a pike ultimate with 44mm offset, I think I might get it . Never had a short offset fork before, I’m interested to see how it feels . Happy new year .
@@Ronnie_rrrip any time. I think it makes sense for a lot of riders and set ups.. I also think people just adapt to what's on the bike! But if you want to go fast as you can, I think it's best to get it absolutely perfect and dialed.. Which is why I have a 44mm on the way to try!
It's not really about matching the offset, because your hands aren't at that same offset due to the bar sweep. And between different bar widths, bar sweeps, even bar rise and roll, everyone's hands will be in a different location relative to the axle even with matching stem length and offset. If matching length to offset happens to feel good for you, it's just because you found the right hand position compared to whatever stem length you had before, and could get the same feeling with a different stem length on a different handlebar. So also mentioned it a bit with the contact patch, but have to remember that the contact patch to steering axis distance changes with both fork offset _and_ head tube angle. So if the relation of hands to contact patch is important, them stem length has as much to do with fork offset as is does with head tube angle (and the bars are mentioned above). Thus, matching stem length to fork offset is only going to be valid for some head tube angles (and some bars) for a given rider.
agree with everything. There are a ton of variables... and you didn't mention peoples body parts and proportions.. what if someones femur is much longer in proportion to their tibia or forearm length versus upper arm length and how they bend in proportion etc. There's a ton of variables. The head tube angle is definitely a factor too, but the steepness of the terrain you're on will influence that too... great comment!
Without body position considered, the stem length determines the leverages you have as it relates to steering. The longer the stem, the larger the sweep, more control, and less twitch. Shorter stems have less sweep, less leverage, faster twitches, and input response...... Now consider how it affects your body postion and throw everything else I said and trash it😂.
I'll discuss width, sweep and rise in another video. I used the same bars on all the stems so that the only thing changing was the stem length and design.
@@TheMarkList Please, you should measure where your grips are in comparison to your stearing axis. Your Stem length does not really matter. If you have a 43mm stem but a riserbar with 50mm rise and 8° backsweep rolled a bit backwards, your grips might be right on the stearing axis. And with the rulesman stem your grips will be behind the stearing axis like on many moto x bikes.
@@EliasSchul yup, I'm well aware of all of this. I'm not changing anything except the stem length and measuring the bar height from the ground to make sure grip height etc is the same,and leaving the bar roll the same. Been riding and racing road, track and mtn bikes since the 80s...been messing with bike set up a long time and try to just use data as a factor. It's why I use motion instruments telemetry to tune my suspension and will never just 'guess' if my fork and shock are balanced etc.
@@EliasSchul Also, the steering axis will ALWAYS be over the center of the fork tube unless your measuring the axis the wheel/axle rotates around. As soon as you put a stem of any length on the fork tube, you're no longer on the axis. Simple geometry. The bars will now be on an arc that is determined by the length of the stem... regardless of sweep and rise, the bars are no longer on the same axis as the fork tube. Where you're gripping the bars doesn't change the axis the bars are rotating on. It will change your hand position and it will possibly have the position your gripping the bars change, but the weight is still going to be transferred to the stem via the bars. This video was about discussing what stem length alone does to ones riding position and weight distribution. That's it. No other factors were changed between stems. This is why i measure the bar height from the ground every time I swapped stems. Also, it's pretty difficult to have your hands in a static determined position on the bars. They are constantly moving and adjusting in a dynamic fashion... so that will also affect how you are moving the bars. Feel free to do a video on sweep and steering axis so that you can explain how the steering axis moves based on the sweep of the bars.
Help! Old guy (58) here trying to adjust to my 2024 Trek Fuel EX's handling. 29er with 160mm fork. Haven't ridden in over 20 years and that was on a 5" travel trail bike with 27.5s. I can't used to the way my front wheel flops back and forth and wanders all over the place in slow speed rough terrain, especially climbing. What could be causing this? Really appreciate your input folks!
@@GODZclaN11 well slow speeds make rough terrain even more difficult. I'd make sure you have plenty of air in your fork. Stiffer is better than softer... You don't want the bike diving into a hole and compressing all the way down to the crown. How tall are you? What reach bike? How much air pressure in fork and tires? Lots to consider
If i can‘t match the offset, i prefer to run slightly longer stems (46 offset and 48 stem, 44 offset and 45mm stem). I think chris porter was on the offset matching wagon a while ago
i think the more stems you try the better.. and for some the offset length works. I agree that you have to try many lengths and see what works best for you. I ran a 43mm and have a 44mm on the way just to see if it might be better. Great comment, thank you!
I'm going to say no. rise in the stem will just affect your upright position. I'm currently on a 44mm williams racing stem with zero rise and love it. I'm also on 50mm rise dh bars. I actually wanted a stem with some rise, but a 44mm with a 31.8mm stem doesn't exist that I know of. The Fraezen stem in 44mm has a rise to it, and it's pretty sweet. If you have 35mm bars, I'd go with that one! Hope this helps. Enjoy the rest of your weekend.
@@TheMarkList only thing I was thinking was that if trying to match stem length exactly to fork offset in mm, a rise in the stem would then require a stem that is slightly longer than 44mm to effectively equal the fork offset because of the different angles?
@@TheMarkList thanks for all of the info btw, great presentation! I happened to see that video you referenced about keeping the stem as close to the fork as possible and advocating much longer bikes. All very interesting stuff.
@@teecee4459 whoever makes the stem takes that into consideration. the length is 44mm with the rise built in. they won't add a rise and then make the stem the wrong length or not account for it.
@@teecee4459 You're welcome. There are a lot of variables to consider. Just know, I'm also optimizing for downhill riding/enduro etc. If you're on a xc bike, things will be way different as you're looking to make it the most efficient in terms of power transfer to the pedals and breathing efficiency etc. Let me know if you have any other questions!
@@TheMarkList 50mm feels great for fast single track! My slack HT hooligan rig is now on bikepacking duties, 50mm is horrendous, 100mm is the sweet spot!
@mokotramp yeah it's so depends on the person, their build, the bike, the terrain, type of riding etc. My focus was on Enduro and dh duties...downhill in super techy terrain
Did also see the video about what benefits it would be to have a really really short stem (18 mm) and that threw me off as I'm also riding a Kenevo SL but a size S3 and I'm 6 foot tall. My body with longer legs and slightly shorter torso made me pick the S3 as the S4 feelt to freakin long (could have gone with a 30 mm stem instead of the factory 50 mm on the S4 but I didn't as the S3 feelt more nimble, quicker manoeuvring and easier to flip around on bike parks/trails. Anyway, looking at RAD I was almost spot on but had to increase the reach/stack with 10 mm soo I picked a Renthal Apex 35 60 mm stem and flipped the flip chip to high. Also went with a Oneup 35 mm carbon handlebar with 35 mm rise - increasing the stack with 5 mm. Oboy was that spot on! It turns quick with high precision both on tight techy parts, high speed runs - all with a ton of grip on the front wheel. So a suggestion for you would be to make a new video and try an even longer stem - 60 mm - and see how that feels! 😊
I’d love to hear your thoughts on trying a 40mm then run back to back on a 43mm and see what you think. I have 40mm on all my 44mm offset as that’s the best option I can find so far. Also, that trail looks awesome. Is it a green or blue?
@@TheMarkList What did you find in 44mm? I’m using the i9 A35s but am open to options of equivalent quality no longer than 44mm. OneUp Carbon bars on all the bikes set to the HTA per OneUp specifications.
This is for a long travel bike? Not sure this applies to my XC bikes. I am also experimenting with finding the perfect cockpit. So many factors, I get overwhelmed with every little detail.
@@usmceric1 absolutely correct. Not optimizing for pedaling or wattage output. You'll want to get fitted like a road bike. This is for Enduro/downhill.
@@bostondye3736 I'm running the Williams Racing 44mm stem and loving it. I'm going to do one more video on the topic and will be quoting you as your comment is one of the best!
@@TheMarkList the 45mm pro taper is my go to but recently put the 50mm back on for my local trails after not running it for 3 years and I was surprised how much I liked it. But with the higher speed turns at the bike park I feel like it might be too nervous.
@@bostondye3736 yeah, i've only been riding very tech/dh type runs this summer at Mammoth Bike park.. the dirt here is super deep loose pumice and makes "steering" very interesting to say the least.
If the sweet spot is matching the fork offset and stem length, then manufactures need to start offering the common fork offset lengths because there’s not many options available.
@@cletussurfsalot7190 yeah I'd double check your offset to match what it is... Also reach and bike fit do play a role too. I feel that taller riders seem to gain more benefits from matching it but that's not based on a lot of data! :)
My preference for tight single track or fast downhill is not to have a bike that is too precise. I crash and/or wash out way more often with a precise bike. I put it in the category of twitchy. If I'm making very quick adjustments at speed, it gives me a feeling of under steer. I just don't have the finesse I think it comes from riding motorcycles all my life.
When you take into consideration head angle, axle to center of bars length and with most forks being 44mm offset, it’s just an arbitrary number. The stem matching the fork offset id think is meaningless. Not saying it won’t work for some people or some setups but all this does is leave everyone where we already are…try many things until you find what works. A 45mm stem is middle of the road for mountain bikes, it’ll most likely feel good for a lot of riders. Side note, I tried the rulezman stem (still own it) you’re wild with 50mm rise bars and that stem 🤠
Every stem has a rise, so to have the same length as the fork offset the stem has to be longer. And what about backsweep and rise of the bar. And spacers shorten rise. ong reach and short stem work better. But if reach is, no way a short stem that has the same length as yor fork offset is going to work.
Yup a ton of variables to look at and consider. There's not one answer or setup that works for every person. You could also factor in terrain, type of riding and mtb discipline. Also, the geometry of the frame, your head tube angle etc etc.
For road bikes and XC/trail, yes.... But for downhill and Enduro where we aren't worried about wattage or maximizing power output, then how you set up the cockpit will be totally different.
@@TheMarkList 🤣 yeah, exactly. When I feel my front wheel washin or drifting, or on the incredibly rare occasions I've front wheel wiped out, it's almost exclusively because I am not loading the front tyre enough, that does not mean excessively or exclusively loading, just if your drifting in loose over hard or when it's gravely etc (not talking about slick roots/mud that's a different scenario) then you need to play with your style and technique to get traction. Modern tyres and compounds are insane compared to the likes of Panaracer Fire XC and similar from the early 00's, you need to be in goose crap on an ice rink polished slick roots to come unstuck these days, but again you need a different approach for that scenario. As some one who had built many bicycle frames, been a mech on and off for over two decades I can assure you that the 1-2 mm difference in stem length has far less influence on where your weight is loaded on the front wheel than you do, you likely weigh about 4 times your bike. Also, spacers unser the stem, bar height and how far you roll the bars forward or behind the zero point will have a huge difference on stack, reach and feel vs two standard style stems that are a few mm longer or shorter. My general guidance for fellow riders or in the past customers was to create a cockpit that feels comfortable when seated for climbs but most importantly, when on the pedals, dropper down and in the ready/neutral position. If you can move comfortably and are not too cramped or stretched you will be able to exert better influence over the bike. Whilst I'll admit my technique is faaaar from perfect, the basic principle still works, twist the upper torso from above the hip, shoulders to the inside of the corner, bum outside over BB stay loos and conform/work with how the bike moves when things do step out, look through corners and make sure you don't hang back so much your front washes out on you, a little pressure on the grip that's to the outside of the turn goes a long way, but your wight has to be over the bike not in free space on the inside of the turn. Err towards level pedals unless it's a very flat or off camber turn also is an over simplification. I have 44mm offset forks on a 63. 5° hta with a 35mm long stem on OneUp 30mm rise rolled back about half a degree from zero, about a 1320mm wheel base and 160mm fr/rr travel. This is not to discredit your video, or discourage, I enjoy your content, and yes I'm some random dude offering unsolicited advice, but I just know from experience some people end up playing with stuff that costs money when they can get the gains for free. Tldr, technique is more important than parts, but comfort/freedom in the cockpit is supportive of good technique. Anyway take it or leave it, and have the most fun riding ♥️, hope I don't cop too much hate for my opinion ✌️.
@@jd4000 all good! And yes, all that influences how you ride and more.. How about body build and proportions? Long upper body and short legs or the opposite... How much do you weigh? Are you fit or fat? Nimble or stiff? Lots to think about... Been mtn biking since 94' when stems were long like road bikes and 90mm of elastomers for a front fork and no dropper... Also raced kilo on the track in the 80s and 90s...so seen a lot and done a lot. Thanks for the great comment! I'm the worst at tight hairpins on off camber single track. I blame it on my height! Lol
Yeah...i believe body size matters...but instead of worrying about steem and steering...you were gasping for breath on that last run...and it wasn't so bad on the other runs...that trail didn't seem to be a incline or very long.. .you may want to see a Dr about that breathing or stop doing what your doing on rain 🌧 days...JS
@@TheMarkList I have built recumbent bikes and choppers with very flat steering angles and can tell you that the stem is much less important than the fork offset or the trail. If you need further professional advice, I can highly recommend the hardtailparty channel but of course also the website of Peter Verdone Design.
@@bertkreft9689 this is for Enduro/downhill application.. And if you look at the word cup dh or ews racers and what they are running, I'm pretty on point. I've been racing at a national level since the 80s on the road, track and dirt (mtb) and have worked with custom frame builders on all those disciplines. One bike designer isn't the answer to everything.. And if he's the best, show me what frames at the world cup level he's designed? I like real world examples and data. A recumbent has ZERO to do with downhill or Enduro... So if you want to discuss bike design or kinematics, get on the same page. If I did a video on recumbent design and tried to compare it to downhill, I'd be the laughing stock of RUclips....
New to mountain biking but also an engineer and have been obsessing over this topic since I started. It blew my mind how much different small changes in frame reach and stem length feel. For example a 440/50 feels like a completely different bike than a 455/35 frame/stem despite having identical effective reach of 490, which is something I tried while picking a frame size.
My conclusion, for Trail/All Mountain an equal Stem/Offset is ideal. The bars move in the exact same path as the front tire making it incredibly intuitive and balanced. For XC/Climbing you want a stem longer than offset to get weight forward of the tire to keep it down. And for Downhill you want it behind offset to keep from having a tendency to rotate over the axle (OTB). By how much I do not have nearly enough experience or testing to say what those values are. But I think most people would be best served by something around +/- 5mm of offset, which way depending on what you typically do more of. This theory is reinforced by 40-50mm stems and 44mm offsets being the most common.
Well also remember that for XC, you want a fit more akin to a road bike to maximize wattage output and efficiency.. Look at Nino schurter etc... Their bikes are more like a tour road bike in terms of fit. I was a competitive road and track cyclist for years and the fit is much different than Enduro/downhill.. But your intuition is spot on..
@@TheMarkList Yeah XC was probably the wrong terminology for what I meant to say. It probably would have been more accurate to say for Technical Climbing or something akin to that. It’s amazing how something as simple as a bike can become such a complex engineering problem around geometry. I’ve done a little bit with race car suspension design, and it’s not that dissimilar, just a different application. Enjoyed your video though, good exploration of the topic not many people talk about.
@@sethrich5998 suspension is such a cool thing to dive into.. on any type of vehicle.. I'm a big fan of telemetry and data... it beats guessing or "feel" ... glad you enjoyed the video, but yes, technical climbing versus downhill, totally different applications and setup
@@TheMarkList Oh definitely. Yeah we did instrumentation and data acquisition on our prototype suspension for design iteration and for race setup. It was with the Formula SAE team at my college if you’ve heard of that.
"The bars move in the exact same path as the front tire"
Except only the center of the bars moves the same as the front wheel. Your hands are out at the ends, and not at the same offset due to backsweep, do not move at all like the front wheel. And a really important aspect of the front wheel is the contact patch, and its relation to the steering axis, and your hands, changes with head tube angle, so matching stem to offset is going to be valid for some head tube angles.
It's more about trying different stem lengths than about matching lengths.
I'm running a 35mm Spank stem, w/ a 60mm rise Spank handlebar, on a 44mm fork offset, all on a bike with a 455mm reach. I've messed around with various stem and bar combos, and this weirdo setup actually feels great. A more upright stance, allows me to really push hard into corners to load the front, yet not feel like I'm over the front when launching into the steeps.
@@jokermtb if it works, use it! There's definitely so many variables to look at!
I bought my first new eMTB there. I've just put a Funns Equalizer V2 stem (42mm, 35mm thicker bar the new one) on my Fox 38s 27.5in, and I'm loving it. It's spot-on for me. The 35mm was just too short, and the 50mm standard was just too far over the front, putting a lot of weight down on the forks. I'm 5'9" on a 20in large frame Cube Stereo 2024 Action Team 160.
With Burgtec Ride High 38s cut to 780mm with those Peaty's Monarch grips, oh, it's nice now! It feels more responsive and stable, and it's just unbelievable for climbing! It took a few tries, but I got there!
5'9" on a 480mm reach bike is pretty wild. If all you are climbing is fire road and only doing DH runs then cool. For anything else, you have fallen into the trap of longer=better. Obviously body proportions play into sizing but 480mm is a LONG bike.
From a 35mm lenght to a 50mm Deity cooperhead made a HUGE difference, more relaxed, better fit, good tracking and cornering. The bike is alive, pop better at any needed situations and great at full speed. That does work superbly for me.
good to hear! always great when things work and feel good. Trying different setups is key!
Just ordered 50mm high rise bars for a . more upright moto feeling I got a 2024 polygon xtrada 7 hardtail the stems low as it is but the factory bars are maybe 10mm rise I'm so leaned over great for climbing but sucks for long rides
The video I have been waiting for.
I ride a 2020 Jeffsy, my first upgrade was swapping m1900 to stans flow ex3 with hopes. Not sure why the steering went heavier, but just decided in spring to use my premium Pike ultimate 51 offset over 42 yari, also upfork to 160 on a 150mm stem.
I'm not so OTB now, but funny I didn't think I was that heavy over the bar at 150mm lol. Steering is lighter now than out of the box, quicker response, and already better cornering. I'm going to keep an 800mm bar for now. Oh, and less pedal strikes now. I was never worried about upforking, but that 9 degree difference did.
@@koretell I'm on 780 bars, usually run 770 and I have a huge wingspan... I think a lot of people ride too wide. Good to see you are experimenting with your setups. It takes a lot of time and patience and sometimes money to get it right! Thanks for the comment and for watching. Appreciate it!
I found this video, and am actually shocked. I messed around with stem length because of back pain, and I run a 50mm on my 51 offset fork, and a 40mm on my 44 offset fork, and when I did the 40mm on the 44 I had replaced the 50mm with it… stumbled across way better handling on accident really. Then I wanted to try the 50mm on place of old 70mm length stem just outta curiosity. Never understood why both bikes got so much better with handling, and this video matches my findings, and gives me some reasoning on what’s happening in my case as well. Thanks man! 🎉
@@robsmith7681 glad you got your stuff dialed and handling well.. Sometimes we stumble on to solutions that don't make sense! Thanks for the comment!
I jist started the process of buying components to build up a frame. I'll have to check this out and see how it works for me. Thanks for the video on this subject!
@@gutzboy1 absolutely! Let me know if you have any questions about bars, grips, stems etc
I loved the ergonomics on my hard tail (long and low ) and really struggled to get on with my full suspension trail bike. After changing forks ,bars and stems I settled on a 60mm stem ,bars rotated max forward. This over the front body position by far suits me best as I ride trials sections for fun also. It’s also helped curb my poor front wheel high jumping technique. I honestly could not ride a high short stem. On aside note, I find the more you hang off the rear of the bike the more you are a passenger especially in the air. Chin over the stem almost always gives more control, I find anyhow.
2020 Hightower medium. I’ve run a 35mm stem and the bike felt way too short. Went back to 50mm and it’s been perfect. The bike was alway washing out the front tire with the 35.
nice job Mark!
thanks brother!!
I just ordered some 50mm high-rise bars my stem is factory length on my 2024 polygon xtrada 7 ❤❤will see how they feel saturday when they get here
'i love my 50mm rise Enve DH bars... i think a more upright position suits descending and downhill the best!
Fantastic video! Provides me with some knowledge to make better decisions in my build out. Also, Mammoth? I assume you know my sister and brother-in-law, Rob and Cheryl Witherill.
@@RickCoreyRealEstate I do not know them.. I ride downhill and mostly pretty technical terrain and I'm usually the only one I see on the trail... And glad you got some value from the video!
A real experiment would be to get the 37mm lowers for your fork. Then swap between your current 44mm offset and the 37mm offset and see if the bike feels more or less balanced with matching stem lengths.
If you feel more comfortable with a shorter stem on a shorter offset and a longer stem on a longer offset then you’ll know whether there is a correlation between offset and stem length.
I've matched offsets on my dh bike and now on the Kenevo Sl and on both it's been pretty great...frame reach will be something interesting to look at too... Am I on a small bike or one on the larger side ? But great way to look at data and to see if results compare! Thanks for the great response!
I ride a Merida with a 51mm fork offset. It came with a 40mm offset, and I can't even count the number of times I washed out the front end and crashed. After trying different stem lengths, I settled on a PNW 50mm stem. Since then, my bike hasn't washed out once, and I feel a whole lot more confident.
it's nice when things work well! I had some same issues with some shorter stems which I mentioned in the video. Glad you're getting things dialed!!
44mm offset and 40mm stem with 5mm backxwssp and 12mm rise. 👌
Been playing with stem length, stem spacer, different bar sweep and rise, and I’m now settled wit 35mm stem and 40mm rise bar. What I could say about all these years of experiments is bar roll and your muscle dominance. If you hv stronger lower body as in stronger hip and legs you will be more leaning forward liking shorter front end and higher rise bar. If you hv stronger upper body then it’s the opposite
@@liwx the size of your body matters too....long legs or long arms or the opposite and also the proportions
I think it depends on the bike geometry as well , a 35mm stem felt great on my old bike , a hardtail with a 63.5 degree head angle and a 51mm offset . My new bike is a full suspension with a 65 degree head angle and 51mm offset . The 35mm stem felt too short with too much weight on the rear and a 50mm stem felt better but the front end felt floppy if that makes sense . So i went with a 43mm stem and it felt perfect .
@@justgo4033 yeah it depends on a lot of things. Type of bike you are riding, geometry, Terrain etc. In terms of Enduro and downhill and riding steep technical terrain, I think it's the sweet spot. I know I'm not the only one who keeps going back to this school of thought. I've tried just about every length and where it puts you over the front axle. Plus, everyones riding style and body proportions are different... So go with what's comfy and fast! Happy new year!
@ I found a good deal on a pike ultimate with 44mm offset, I think I might get it . Never had a short offset fork before, I’m interested to see how it feels . Happy new year .
@justgo4033 44mm offset is pretty common on most 29er forks... Depending on the brand and travel...
Saw the same video that Brian made and have been stem curious for a while now… gonna try it out. Great video thanks for sharing!
@@Ronnie_rrrip any time. I think it makes sense for a lot of riders and set ups.. I also think people just adapt to what's on the bike! But if you want to go fast as you can, I think it's best to get it absolutely perfect and dialed.. Which is why I have a 44mm on the way to try!
It's not really about matching the offset, because your hands aren't at that same offset due to the bar sweep. And between different bar widths, bar sweeps, even bar rise and roll, everyone's hands will be in a different location relative to the axle even with matching stem length and offset.
If matching length to offset happens to feel good for you, it's just because you found the right hand position compared to whatever stem length you had before, and could get the same feeling with a different stem length on a different handlebar.
So also mentioned it a bit with the contact patch, but have to remember that the contact patch to steering axis distance changes with both fork offset _and_ head tube angle. So if the relation of hands to contact patch is important, them stem length has as much to do with fork offset as is does with head tube angle (and the bars are mentioned above). Thus, matching stem length to fork offset is only going to be valid for some head tube angles (and some bars) for a given rider.
agree with everything. There are a ton of variables... and you didn't mention peoples body parts and proportions.. what if someones femur is much longer in proportion to their tibia or forearm length versus upper arm length and how they bend in proportion etc. There's a ton of variables. The head tube angle is definitely a factor too, but the steepness of the terrain you're on will influence that too... great comment!
Without body position considered, the stem length determines the leverages you have as it relates to steering. The longer the stem, the larger the sweep, more control, and less twitch. Shorter stems have less sweep, less leverage, faster twitches, and input response...... Now consider how it affects your body postion and throw everything else I said and trash it😂.
@@mathewselin8704 yeah, tons of variables to consider. Steepness of terrain being a big one to consider too!
How u gunna make a vid like this and not talk about bar back sweep?
I'll discuss width, sweep and rise in another video. I used the same bars on all the stems so that the only thing changing was the stem length and design.
Great job on this
@@TheMarkList Please, you should measure where your grips are in comparison to your stearing axis. Your Stem length does not really matter. If you have a 43mm stem but a riserbar with 50mm rise and 8° backsweep rolled a bit backwards, your grips might be right on the stearing axis. And with the rulesman stem your grips will be behind the stearing axis like on many moto x bikes.
@@EliasSchul yup, I'm well aware of all of this. I'm not changing anything except the stem length and measuring the bar height from the ground to make sure grip height etc is the same,and leaving the bar roll the same. Been riding and racing road, track and mtn bikes since the 80s...been messing with bike set up a long time and try to just use data as a factor. It's why I use motion instruments telemetry to tune my suspension and will never just 'guess' if my fork and shock are balanced etc.
@@EliasSchul Also, the steering axis will ALWAYS be over the center of the fork tube unless your measuring the axis the wheel/axle rotates around. As soon as you put a stem of any length on the fork tube, you're no longer on the axis. Simple geometry. The bars will now be on an arc that is determined by the length of the stem... regardless of sweep and rise, the bars are no longer on the same axis as the fork tube. Where you're gripping the bars doesn't change the axis the bars are rotating on. It will change your hand position and it will possibly have the position your gripping the bars change, but the weight is still going to be transferred to the stem via the bars. This video was about discussing what stem length alone does to ones riding position and weight distribution. That's it. No other factors were changed between stems. This is why i measure the bar height from the ground every time I swapped stems. Also, it's pretty difficult to have your hands in a static determined position on the bars. They are constantly moving and adjusting in a dynamic fashion... so that will also affect how you are moving the bars. Feel free to do a video on sweep and steering axis so that you can explain how the steering axis moves based on the sweep of the bars.
Help! Old guy (58) here trying to adjust to my 2024 Trek Fuel EX's handling. 29er with 160mm fork. Haven't ridden in over 20 years and that was on a 5" travel trail bike with 27.5s. I can't used to the way my front wheel flops back and forth and wanders all over the place in slow speed rough terrain, especially climbing. What could be causing this? Really appreciate your input folks!
@@GODZclaN11 well slow speeds make rough terrain even more difficult. I'd make sure you have plenty of air in your fork. Stiffer is better than softer... You don't want the bike diving into a hole and compressing all the way down to the crown. How tall are you? What reach bike? How much air pressure in fork and tires? Lots to consider
I've been playing with the for years. Ashamed to admit how many stems I have in my parts box.
@@flyingnorseman I'm acquiring quite the collection myself! So I feel your pain! But that's how you learn and get better!
Stems and bars, you should see my collection. Let me know if you need new grips, I have a box full.
@@Klunker1 love it. Rev grips for the win!
If i can‘t match the offset, i prefer to run slightly longer stems (46 offset and 48 stem, 44 offset and 45mm stem). I think chris porter was on the offset matching wagon a while ago
i think the more stems you try the better.. and for some the offset length works. I agree that you have to try many lengths and see what works best for you. I ran a 43mm and have a 44mm on the way just to see if it might be better. Great comment, thank you!
Do you need to have a 0 rise stem fir this to work?
I'm going to say no. rise in the stem will just affect your upright position. I'm currently on a 44mm williams racing stem with zero rise and love it. I'm also on 50mm rise dh bars. I actually wanted a stem with some rise, but a 44mm with a 31.8mm stem doesn't exist that I know of. The Fraezen stem in 44mm has a rise to it, and it's pretty sweet. If you have 35mm bars, I'd go with that one! Hope this helps. Enjoy the rest of your weekend.
@@TheMarkList only thing I was thinking was that if trying to match stem length exactly to fork offset in mm, a rise in the stem would then require a stem that is slightly longer than 44mm to effectively equal the fork offset because of the different angles?
@@TheMarkList thanks for all of the info btw, great presentation! I happened to see that video you referenced about keeping the stem as close to the fork as possible and advocating much longer bikes. All very interesting stuff.
@@teecee4459 whoever makes the stem takes that into consideration. the length is 44mm with the rise built in. they won't add a rise and then make the stem the wrong length or not account for it.
@@teecee4459 You're welcome. There are a lot of variables to consider. Just know, I'm also optimizing for downhill riding/enduro etc. If you're on a xc bike, things will be way different as you're looking to make it the most efficient in terms of power transfer to the pedals and breathing efficiency etc. Let me know if you have any other questions!
Sixpack Millenium stem comes in 31.8mm clamp and 45mm length, they are from germany though.
@@thegarageluthier I ended up getting the Williams Racing in a 44mm... Love it!
My fork off set is 51mm, I run 100mm stem! 🤣
Too many folks running stems too short! 👍
@@mokotrampalso depends on the type of riding you do.. That's very common on an XC set up
@@TheMarkList 50mm feels great for fast single track!
My slack HT hooligan rig is now on bikepacking duties, 50mm is horrendous, 100mm is the sweet spot!
@mokotramp yeah it's so depends on the person, their build, the bike, the terrain, type of riding etc. My focus was on Enduro and dh duties...downhill in super techy terrain
Did also see the video about what benefits it would be to have a really really short stem (18 mm) and that threw me off as I'm also riding a Kenevo SL but a size S3 and I'm 6 foot tall. My body with longer legs and slightly shorter torso made me pick the S3 as the S4 feelt to freakin long (could have gone with a 30 mm stem instead of the factory 50 mm on the S4 but I didn't as the S3 feelt more nimble, quicker manoeuvring and easier to flip around on bike parks/trails. Anyway, looking at RAD I was almost spot on but had to increase the reach/stack with 10 mm soo I picked a Renthal Apex 35 60 mm stem and flipped the flip chip to high. Also went with a Oneup 35 mm carbon handlebar with 35 mm rise - increasing the stack with 5 mm. Oboy was that spot on! It turns quick with high precision both on tight techy parts, high speed runs - all with a ton of grip on the front wheel.
So a suggestion for you would be to make a new video and try an even longer stem - 60 mm - and see how that feels! 😊
@themarklist Definitely needs to try a 50-52mm stem.
I’d love to hear your thoughts on trying a 40mm then run back to back on a 43mm and see what you think. I have 40mm on all my 44mm offset as that’s the best option I can find so far. Also, that trail looks awesome. Is it a green or blue?
Shotgun is a black diamond. I'm going to go from a 43mm to a 44mm....so will see what 1mm does!
@@TheMarkList What did you find in 44mm? I’m using the i9 A35s but am open to options of equivalent quality no longer than 44mm. OneUp Carbon bars on all the bikes set to the HTA per OneUp specifications.
@@justinfournier1285 the 44mm hasn't arrived yet... So to be determined!
@@TheMarkList Sorry I mean what brand is it? Thank you!
@@justinfournier1285 Williams Racing out of Australia. Fraezen makes a 44mm for a 35mm one up bar
Stop !!! you made me buy a new stem. Jeezzz loiuz. I just keep dropping money on my bike.
I probably have 6 stems.... So I feel ya!
Be interesting to see how the wrp stem goes
@@dtran1742 riding it today!
Steering hand offset. Look it up!
argh. so homesick. I miss mammoth
@@nathantoney.1501 it's been very warm!
This is for a long travel bike? Not sure this applies to my XC bikes. I am also experimenting with finding the perfect cockpit. So many factors, I get overwhelmed with every little detail.
@@usmceric1 absolutely correct. Not optimizing for pedaling or wattage output. You'll want to get fitted like a road bike. This is for Enduro/downhill.
An easy way to think of it is this… 44mm is the base. Shorter leads to understeer. Longer leads to oversteer.
@@bostondye3736 absolutely!
@@bostondye3736 I'm running the Williams Racing 44mm stem and loving it. I'm going to do one more video on the topic and will be quoting you as your comment is one of the best!
@@TheMarkList the 45mm pro taper is my go to but recently put the 50mm back on for my local trails after not running it for 3 years and I was surprised how much I liked it. But with the higher speed turns at the bike park I feel like it might be too nervous.
@@bostondye3736 yeah, i've only been riding very tech/dh type runs this summer at Mammoth Bike park.. the dirt here is super deep loose pumice and makes "steering" very interesting to say the least.
If the sweet spot is matching the fork offset and stem length, then
manufactures need to start offering the common fork offset lengths because there’s not many options available.
@@cletussurfsalot7190 more are....Tenet, Fraezen, Williams Racing Products etc.
@@TheMarkList I’m 6’3 on a XL Trek slash Lyrik for with Deity 35mm stem 38mm bars, actually feels pretty dialed.
But not opposed to try 44mm
@@cletussurfsalot7190 yeah I'd double check your offset to match what it is... Also reach and bike fit do play a role too. I feel that taller riders seem to gain more benefits from matching it but that's not based on a lot of data! :)
on my bike l use a BMX set-up with a low/mid bar ect...
My preference for tight single track or fast downhill is not to have a bike that is too precise. I crash and/or wash out way more often with a precise bike. I put it in the category of twitchy. If I'm making very quick adjustments at speed, it gives me a feeling of under steer. I just don't have the finesse I think it comes from riding motorcycles all my life.
@@justsayin3600 good point! Thanks for the comment
oh hi mark
@@micleabogdan886 Hi!
When you take into consideration head angle, axle to center of bars length and with most forks being 44mm offset, it’s just an arbitrary number. The stem matching the fork offset id think is meaningless. Not saying it won’t work for some people or some setups but all this does is leave everyone where we already are…try many things until you find what works. A 45mm stem is middle of the road for mountain bikes, it’ll most likely feel good for a lot of riders. Side note, I tried the rulezman stem (still own it) you’re wild with 50mm rise bars and that stem 🤠
@@JerrySpallone I agree, but also think things are different with taller riders over 6'1...there's way too many variables to look at.
being 6.4 tall i ride a 35 mm stem and 675 mm toptube@@TheMarkList
Every stem has a rise, so to have the same length as the fork offset the stem has to be longer. And what about backsweep and rise of the bar. And spacers shorten rise. ong reach and short stem work better. But if reach is, no way a short stem that has the same length as yor fork offset is going to work.
Yup a ton of variables to look at and consider. There's not one answer or setup that works for every person. You could also factor in terrain, type of riding and mtb discipline. Also, the geometry of the frame, your head tube angle etc etc.
Stem length is to dial in ride quality and rider fit.
For road bikes and XC/trail, yes.... But for downhill and Enduro where we aren't worried about wattage or maximizing power output, then how you set up the cockpit will be totally different.
3 seconds of info in an 18min video.
maybe 4 seconds if you use a stopwatch :)
My brother in bicycle Christ, have you tried leaning forwards.
Lol... If I leaned forward it might put weight on the front of the bike... :)
@@TheMarkList 🤣 yeah, exactly.
When I feel my front wheel washin or drifting, or on the incredibly rare occasions I've front wheel wiped out, it's almost exclusively because I am not loading the front tyre enough, that does not mean excessively or exclusively loading, just if your drifting in loose over hard or when it's gravely etc (not talking about slick roots/mud that's a different scenario) then you need to play with your style and technique to get traction.
Modern tyres and compounds are insane compared to the likes of Panaracer Fire XC and similar from the early 00's, you need to be in goose crap on an ice rink polished slick roots to come unstuck these days, but again you need a different approach for that scenario.
As some one who had built many bicycle frames, been a mech on and off for over two decades I can assure you that the 1-2 mm difference in stem length has far less influence on where your weight is loaded on the front wheel than you do, you likely weigh about 4 times your bike. Also, spacers unser the stem, bar height and how far you roll the bars forward or behind the zero point will have a huge difference on stack, reach and feel vs two standard style stems that are a few mm longer or shorter.
My general guidance for fellow riders or in the past customers was to create a cockpit that feels comfortable when seated for climbs but most importantly, when on the pedals, dropper down and in the ready/neutral position. If you can move comfortably and are not too cramped or stretched you will be able to exert better influence over the bike.
Whilst I'll admit my technique is faaaar from perfect, the basic principle still works, twist the upper torso from above the hip, shoulders to the inside of the corner, bum outside over BB stay loos and conform/work with how the bike moves when things do step out, look through corners and make sure you don't hang back so much your front washes out on you, a little pressure on the grip that's to the outside of the turn goes a long way, but your wight has to be over the bike not in free space on the inside of the turn. Err towards level pedals unless it's a very flat or off camber turn also is an over simplification.
I have 44mm offset forks on a 63. 5° hta with a 35mm long stem on OneUp 30mm rise rolled back about half a degree from zero, about a 1320mm wheel base and 160mm fr/rr travel.
This is not to discredit your video, or discourage, I enjoy your content, and yes I'm some random dude offering unsolicited advice, but I just know from experience some people end up playing with stuff that costs money when they can get the gains for free.
Tldr, technique is more important than parts, but comfort/freedom in the cockpit is supportive of good technique.
Anyway take it or leave it, and have the most fun riding ♥️, hope I don't cop too much hate for my opinion ✌️.
@@jd4000 all good! And yes, all that influences how you ride and more.. How about body build and proportions? Long upper body and short legs or the opposite... How much do you weigh? Are you fit or fat? Nimble or stiff? Lots to think about... Been mtn biking since 94' when stems were long like road bikes and 90mm of elastomers for a front fork and no dropper... Also raced kilo on the track in the 80s and 90s...so seen a lot and done a lot. Thanks for the great comment! I'm the worst at tight hairpins on off camber single track. I blame it on my height! Lol
Nothing should be hard on an EBIKE 😂😂
@@MTB_FANATIC99 hah! Right?
The offset and stem aren't related.
@@sladeoriginal they aren't related but it does affect where your weight goes.. Just like your head tube angle etc
Yeah...i believe body size matters...but instead of worrying about steem and steering...you were gasping for breath on that last run...and it wasn't so bad on the other runs...that trail didn't seem to be a incline or very long.. .you may want to see a Dr about that breathing or stop doing what your doing on rain 🌧 days...JS
@@James-cs3hp I was toast from a long gravel ride the day before and was really fatigued..hence the heavy breathing!
@TheMarkList ok....that's good , I guess lol....keep on pushing yourself 👍
And putting out the informational videos...🚲❣️
longer tt and shorter stem for progressive riding - check professional advice before making a video - peter verdone design
I looked at your videos and I'm wondering who's professional advice you took?
@@TheMarkList
I have built recumbent bikes and choppers with very flat steering angles and can tell you that the stem is much less important than the fork offset or the trail. If you need further professional advice, I can highly recommend the hardtailparty channel but of course also the website of Peter Verdone Design.
@@bertkreft9689 this is for Enduro/downhill application.. And if you look at the word cup dh or ews racers and what they are running, I'm pretty on point. I've been racing at a national level since the 80s on the road, track and dirt (mtb) and have worked with custom frame builders on all those disciplines. One bike designer isn't the answer to everything.. And if he's the best, show me what frames at the world cup level he's designed? I like real world examples and data. A recumbent has ZERO to do with downhill or Enduro... So if you want to discuss bike design or kinematics, get on the same page. If I did a video on recumbent design and tried to compare it to downhill, I'd be the laughing stock of RUclips....
Cheap stems are easy to come by. Experiment, find the length that works for you, then buy a quality stem of that length