Thank you for this information! Now when I crash my bike due to lack of skills, I can just tell everyone who witnessed it that I made incorrect mechanical adjustments on the bike that resulted in poor geometry conditions!!!
@@juanete838 I bet that you can tie your shoe laces though. I too am an engineer and have worked in motor sports, some of the best test riders and drivers are just useless at all other aspects of life. Good engineers do not make good test riders, this is because they can tell that things are going wrong before most other people would notice. One manager at a car manufacturer in Britain once said to me that it is the job of the engineers to break the vehicle, and it is the driver's job to crash it, adding that it is easier to replace a test rider than it is to replace a good engineer. You will only ever find the limits by going beyond them, and that can hurt, or worse.
I read most reviews, depending on what edition you buy, it's not obvious if the later edition is much improved over the earlier edition, the earlier edition appears a complete nightmare , horrible Italian to English translation, poor math, and very poor editing in general. Looks like some people loved it ,and others found it a waste of time , trying to figure out where the poor translations vs bad math and editing start and finish. :shrugs: , I''ll pass, will look for something else, but glad to know there are books out there that explain bike geometry.
Right. Not even a lot of mechanics out there fully understand this too so you can even pay someone to help unless you really want to pay top dollar for someone's time. I'd rather not ruin my bike.
I'm currently doing a study about motorcycle suspension and some dynamics and this video has summarized a big part of a few books that I've read, which were kind of hard to understand. Thanks for making this, made it really easy to understand, props for that.
Not to be that guy, but something missing on the anti-squat portion is the fact that under acceleration the rear ride height of the bike actually increases not decreases which is counter intuitive. This is doe to the torque vector of the drive chain acting on the axle which sits below the pivot point of the swing arm and the drive sprocket. Or in other words, the drive sprocket is trying to pull the rear wheel to the engine through the shortest distance which is under the bike. If the axis of rotation of the swing arm and drive sprocket were co linear or the rear axle where positioned above the pivot point of the swing arm than the opposite effect would occur. This is one of the reasons why power must be applied smoothly when exiting a corning. To much throttle will shift the CG forward and up. Once rear traction is lost the rear immediately drops until it regains traction at which point the suspension violently extends and draws the rear wheel back into alignment with the front resulting in a high side. .
- ... traction wasn't mentioned, would a bike with a lower swing arm angle (more parallel) create more traction on acceleration because the pulling force is more lateral? The initial power would be *into the swing arm, as opposed to *perpendicular to a more vertical set up... So the question is, does traction come from more resistance (low swingarm angle) or less resistance (high swingarm angle) where weight, engine, rider, etc are all equal? I guess I should read the book. The trade off is obviously trail length on the accommodated design? That why cruisers are as they are..? I should read the book. Any hints welcome. Thank you.
i cant be the only one who actually understood what he said as he said it. mechanics isn't that difficult. the important thing is understanding the jargon. at least he didn't drone on about calculus equations.
Great video in general, but the part around lean angle and COG is maybe a bit misleading. Lean angle only becomes dependent COG location when combined with wide tyres (e.g. sports bikes) because the tyre contact patch moves away from the center line of the bike when you corner. For something on skinny tyres the location of COG has negligible impact on the lean angle required for a given speed.
Nice videos mike!! I spent endless nights thinking and reading and searching for all these technical issues and details. Is nice to watch them all in one video. One point still not clear to me is the effect of the height of the neck (steering head) from the ground since is very different between bikes of same category. Seems important to me
“The use of wide tyres causes another difficulty when the bike rolls because the contact patch moves further and further from the bike’s centreline and from its steering axis. The taller the tyre section the more pronounced these effects are; lower sections minimize them, for a given width of tyre. There are several effects. It reduces the camber thrust for a given angle of lean. Ironically, a bike with a higher centre of gravity or with the centre of gravity shifted in towards the turn, will require less angle of lean to balance its centrifugal force.” I took that off John Robinson’s book, Motorcycle Tuning Chassis second edition under the section of contact area in tyres. Perhaps maybe you could do a video why wider tyres need more lean angle to turn and narrow tyres use less. And how how centrifugal force is actually needed to turn with the same bike but different width tyres. Perhaps you can mention why did MotoGP used 16.5 wheels and why some asian drag bikes used bicycle sized wheels on their drag bikes. Thank you in advance
Hey man, I think you can understand this on a video better than with the words of my. Just search how steering works to youtube and click on some animation.
I don't think you explained that part at the end correctly, it should be like this: When you brake: TRAIL decreases, SWINGARM ANGLE increases, WHEELBASE decreases (shortens). When you accelerate: TRAIL increases, SWINGARM ANGLE decreases, WHEELBASE increases (lengthens).
What ? You didn't subscribe yet ?.. Thank you for this very cool and instructive video. Still scratching my head on a few things and on the remark at 9.43. If a lower CoG makes the bike easier to steer in (9.21), then how come a bike with a higher CoG is easier to flicker (9.43) ? I feel like: "Abandon all hope, ye who enter here". I need more neurons... Spare anyone ?
Really cool video. In the end a lot depends on the rider's input, obviously right? I liken tag to hitting a baseball and how quickly your mind has to adapt in the moment. I have good experience on all styles of motorcycle. Great information.
Thanks Mike. Been riding all my life. When I decided to go track riding on a Sportbike i chose one whose frame is near perfect for me... 2018 Aprilia RSV4 RF LE#14 w/wings!😍
Excellent explanations! This information is necessary for both racers and cruisers who want to better their skills by understanding how skills work with the geometry of the bike. Thanks for such a well made video!
Good video, but the concepts are a bit “old”...Trail does nothing, (MotoGP bikes do not have small trails for example) it is just the resulting value of more important things like rake and offset. Higher trail does not mean necessarily more stability if we are talking about different bikes (115 slower to turn than 100), because you can achieve a certain value with infinite combinations (even silly ones). Lower center of gravity does not make a bike more stable in corners, and you confirm this when you say that you need to lean more at a given speed... it is necessary to reduce the leverage that will make the bike tip over during acceleration, that’s the reason why it is lower on sport bikes and why it is lower than the past (less power). And so on. Pay a visit to an Italian site called “Giornale Motori” and look for the tech articles of Federico, a top class engineer, it will explain why a book like the one of Cossalter does look certain thing backwards. Everything starts from CG position and mass distribution on the axes, but it is a long story :)
The centre of gravity heigt don't affects the lean angle, it depends just on weigh/centripetal Force ratio. This depends on the speed and the bending radius, the weigh is uninfluent being either on the numerator and denominator of the fraction. This way it erases itself per each given weigh.... So the lean angle is independant by weigh and just depends on speed and radius...
you're not totally wrong, just stuck in a too simple model of a bike. look at this you'll understand it: s3.amazonaws.com/advrider-photobucket-images/images/d/dealershipids_cg2_zps3dd45ac3.jpg
I'm PERFECT at understanding your video. Because I have virtually 0 experience riding a bike I don't even know what the component's names are, much less how they function. Thus, saying "what" they do will be use ....... to memorize (not understand). The difference between viewers who understand based on _your words_ vs _their intuition_ ... depend on understanding _both how and why._ Both are necessary. Neither are sufficient. When you say raising the bars in the triple clamp means lowering them, people who've never "adjusted triple bars" should become certain of one thing: We don't know what you're talking about. I know; I'll watch someone else's video to understand the principle you're explaining. Wait; is that not your goal..? I'll try with pool hoping it's something I understand that you may not (though you probably will as M.E. are going to understand vectors, rotational inertia, friction and converting linear force for the cue balls combined rotational + linear moment. Inside english will kill the cue ball providing you a larger margins of error in certain instances where being on one half the table is sufficient. Jacking up allows you to jump over and clear an edge of a ball pretty easily (by deflecting it off the table). You can not only jump over cue ball obstructions, but even jump an object ball over an impeding object ball (with the right angle & power). Outside lets you cut a ball despite the humidity, inter-ball friction enough to mitigate the value of cut-induced-throw. Using a thinner shaft will deflect the cue ball less when using side-spin, but, you'll always need to use the exact right offset to compensate for both deflection and the coriolis to pocket balls if the speed is low enough to allow some angular momentum to swerve the cue ball. You can pocket a ball with almost any amount of misalignment (where your feet are relative to your stroke) causing a 'tip-offset' to spin (and deflect) the cue ball ... provided you hit the ball hard enough to minimize the coriolis WITH accurate understanding of the fullness of hit required on the object ball given the type of spin used and the distance from the object ball to the pocket. Likewise, you could also primarily rely on swerve (coriolis) despite not being aligned to pocket the ball; instead relying on the cue ball swerving back across the deflected line (crossing the straight-line path). It will however, require a tremendous amount more visualization & MUCH better feel for the humidity, friction between the balls, the chalk ... and even then, should be limited to balls very close to the pocket which are obstruct by another ball, ,in which jumping it would require getting it up, down, and then not bouncing off the table ... requiring an even higher jump angle (which precludes your head from as naturally seeing the path the cue ball will take. Also, hitting the object ball above the equator magnifies errors because it's essentially a smaller ball ... which makes each millimeter correspond to greater changes in minutes and seconds of angle. Every statements was true, accurate and would be immediately understood by any pool player as such. I wouldn't count on someone who wasn't a pool player understanding any of them though, (unless they already did). Is that still teaching? To know if say, a book I wanted to write were effective, I'd ask people who were incompetent, didn't understand principles, etc., but who wanted to (as in, clicked on your video) if they could explain the principle to me before (confirm they didn't know) and after watching (to ensure my concept was communicated). If they don't, maybe it made sense to me...and would to others _who already knew,_ ... but wouldn't to those who _didn't (or didn't well) already understand.
A big thing that many newbies over look is rear axle position.. Pushing the axle further to the rear will make the bike turn in slower and the moving it forward will make it turn in quicker without even touching the front forks. So try to find the optimal axle length position and if you want to change gearing use different lenght chains to keep it in the sweet spot the rear of a motorcycle is often overlooked but very important for optimal suspension settings
I've been reading the same book in the video "Motorcycle Dynamics" by Vittore Cossalter. It's a fucking pain in the ass to read, and I'm pretty sure it's wrong on multiple points. Really not recommended.
So how the geometry of my 2021 Tracer 9 GT will change when i put a 180/60 rear tyre (instead of 180/55 stock)? And how will affect (fast turning? less stable on top speed? smaller caster angle?) my ride?
good comprehensive video, the model of the aprilia you have is not a rsv4 tho, its a aprilia rsv1000 2005-2009 (3rd gen) model.. I own a factory edition of the 2nd gen myself, amazing bikes
Hi. Interesting and well explained for someone who wants to approach bike setup. There's a part though where I think you probably said something not exactly right, and it's about @ 10:15 where you say that, under braking, trail decreases. My understanding is that trail is a function of the steering angle, offset and tyre diameter and that the fork length (unless you have a raked fork) is not a factor. It is theoretically true that the tyre compresses under braking thus reducing the diameter and affecting the trail, but it's compensated by the fact that the contact patch gets wider (mechanical trail, etc.). Regardless, as I said, well done and nicely put. Ciao
I understand you reasoning, but when breaking hard, the rear lifts and the fork angle changes giving momentarily less trail. Of course, this is compensated by the tyre compression, resulting in more contact surface but less gyroscopic effect. I'm not a mechanical engineer but that's my understanding of that specific moment. Cheers from 🇵🇹✌️
Geometry books would be hard to understand even for an engineer? Who do you think likely wrote the book? Who do you think designs motorcycles? Engineers. You make mc geometry sound like it's more difficult to understand than particle physics or includes some amount of philosophy. Motorcycle geometry is pretty basic stuff. Common sense to some. And you used the term laymen. What are you? A particle physicist philosopher? Steering dampers aren't only for bikes with aggressive trail, they're also for off road applications such as a Baja race bike where rider fatigue comes into play. You should do a video on the BMW coaxial traction system. This is where they put the drive sprocket on the same axis as the swingarm pivot. They learned a lot about chain tension and it's effect on traction because with that deign, the chain tension remains the same throughout the whole rear suspension travel. You'd do a much better job at that than me..and I think it would be a great video! Do it!
1:29 “It will also make the motorcycle *less stable* and, potentially, harder to control.” What exactly does “less stable” mean? I’ve heard this phrase thrown out a lot when talking about changing your motorcycle suspension. But I’ve never heard anyone explain what it actually is. Does it mean your bike will randomly wobble at certain speeds and cause an accident? Does it mean the bike will fall to the side on a whim during riding unless you’re always holding the handlebars really tight? Will the bike just stop suddenly and make the rider fly off the road? Or will the bike jump into incoming traffic if you hit a minor bump on the road? What exactly do you mean by “less stable”?
Hey man, really helpful video I guess you got a Little mixed up in the start related to trail and cg relationship And in the end how during acc the WB will increase due to decrease in swingarm angle which gives stability The trail part maybe I didn't understand correctly.
"over and out" "over" signals your done talking. its now the other guys turn to say something. "out" means your signing off the radio.... so correct speak would sound like. (CALL SIGN) STANDING BY ON CHANNEL ONE SIX OUT".
I have a problem with my ZX-6R where it feels like the geometry is constantly changing. One week when I'm riding at a given speed (±70kmh/45mph), the bike feels great, it's responsive and stable, light & easy to lean in and change direction. A week or two later, riding at the same speed, it feels like the opposite. Unstable (head-shaking), poor handling feedback (steering feels lazy and "delayed" almost.) It requires more effort on the bars to change direction. The suspension also doesn't feel consistent. Sometimes it feels stiff and other times it feels too soft, even though the preload and damper settings have not been changed Does anyone know what could be causing this? I've had my front and rear spring rates increased to match my weight, and I've had my sag set correctly as well. I don't know what to do anymore.
There is a ratio between trail and forks angle. And spring rate characteristics contributing to bike geometry while suspension is loaded mid-turn with cornering force.
Tire-width combined with weight is determining speed at given angle in turn. THEREFOR is a Motard, weighing 120 kilos on a 160 section tire, much faster mid-corner than a 200 kilo sportbike on 200-section tire.It is the offset of center of gravity and contact-patch that determins centrifugal power in addition to speed and angle.
I never understood why some guys like to extend the forks on their motorcycles to ridiculous angles (i.e., Easy Rider/“choppers”). I guess it is a ‘statement’ of rebellion or something along those lines. But to me those “choppers” look stupid, and the clowns that ride them are definitely making a statement about themselves. It would make for great comedy to watch the Hells Angels vs. The Mongols vs. Brother Speed vs. The Bandidos, etc.... in a Grand Prix style road race on their choppers. The wrecks would be outrageously entertaining along with the fights that would ensue shortly thereafter.
Need help. It hurt my brain trying to make sense out of it. In my common sense, low ground clearance = low CoG = (+) stability. That though makes sense in a straight, right? I increase both tyres size in 1:1 ratio. I experience a significant head shake in straight line, scared the shit out of me. So my point is. If you move fork tube up it will decrease trail and vice versa. Doesn't higher ride high make it less stable? Or the consept completely whoosh me.
That’s a long way of saying “yet again, Harley has spent time and money to produce lots of noise while being one of the poorest handling and performing motorcycles”. But they do go blubblopblapbrapblopblupblop. Cue South Park noises.
Small issue with trail making it possible for a bike to stay upright. Experiments have shown that even reversing the trail doesn’t cause the bike to become unridable. Obviously it’s complicated but in short a bike 🚴 or 🏍️ will continue to do its thing with some pretty radical departures from conventional design. Sure that will cause things to function in a less than ideal way, but they still function.
You're mentioning @10:14 when the rider brakes (decelerates) the swingarm angle increases however @ 10:50 while the rider accelerates, the swingarm angle ALSO increases which doesn't make any sense, could you explain how?
Somethings you didn't mention is gyroscopic effect, unsprung weight, spring rates and dampening all very much apart of the steering, stability discussion, peace...
I've been sending people to watch this video many times, but on today I was searching for something, heard the phrase on 6:15 and wondered - how actual load transfer is related to suspension travel? :) Not sure that it's correct to state that anti-squat helps with load transfer...
there's some wrong ..you show moving up forks and lowering the front of the bike . but this only modification don't lowers the back like you do on the model ! .. and dont makes a smaller anti squad angle !
Mx rider here. So bigger offset triple clamps decreases trail which in theory would make the bikes more agile/less stable. Then why in real world effect does more offset seem to make the bike more stable. It is very common on motocross bikes for riders to change from 22mm offset clamps to 24mm clamps to get a more stable ride. Is this effect due to the lengthening of the wheel base?
Regarding trail: This is also relative to speed. An off-road bike can live with a longer trail because of the lower speeds, lower weight, and lower weight of the engine internals, and thus the lower gyroscopic effect. In regards anti squat: Motorcycles with swing arms - shaft driven even more than chain driven - have a natural anti squat tendency. In regards to centre of gravity: This can't be isolated to the bike alone, because it's very dependable on the mass of the rider. And the movement of the rider/the second chassis. The centres not afflicted in the same way by the rider is the geometric centers, like pitch, dive, squat etc, tough the riders moving mass will affect the behaviour. It's easily doable to make a bike anti dive, regardless of rider weight. Or am I completely off the mark? [Edit: Funny typo :)]
@@anthonyefarr :) Less rotating mass, or less inertia? What would be the correct phrase? I could of course write it in my own language, but on the world stage that language don't seem to fly ;)
You promised that by the end of this video these terms will start making more sense to us... Now that the terms make sense I know I know nothing. Sgt. Shultz.
good vid, one ambiguity at 10:58. You mention a decrease in wheelbase as weight transfers to the rear but comment that this adds to stability, which contradicts the correct point you made earlier in the video re wheelbase. Sure its only one factor in play at that point but just sayin....
Thanks Johnny Sins
Thank you for this information!
Now when I crash my bike due to lack of skills, I can just tell everyone who witnessed it that I made incorrect mechanical adjustments on the bike that resulted in poor geometry conditions!!!
Nah dude, there must be something wrong with the tires..... :-)
Thanks for the reveal :P
So lack of mechanical skills as well as riding skills...
Sweet excuse making skills!
LOL
Anti-Squat sounds quite slavphobic.
Boris and Anatoli want to know your location.
They should have bough soviet motorcycle like Урал: Ural (basically a copy of bmw engine)
As a Slav... that makes me sad 🙁... 😂
ahaahahahahahahahaahahahahahahahhaah as a slav....i love this :D
Please change this term, it offends me and my culture.
I need a KTM scale model like that to fool around with at the office
Hahahahaha your comment made my day, sir.
Amazon carries these.
best comment ever!
Me, too.
The rider is just an onboard engineer.
Believe me. As an engineer I cant onboard like the pilots on the video, lol.
@@juanete838 I bet that you can tie your shoe laces though. I too am an engineer and have worked in motor sports, some of the best test riders and drivers are just useless at all other aspects of life. Good engineers do not make good test riders, this is because they can tell that things are going wrong before most other people would notice. One manager at a car manufacturer in Britain once said to me that it is the job of the engineers to break the vehicle, and it is the driver's job to crash it, adding that it is easier to replace a test rider than it is to replace a good engineer. You will only ever find the limits by going beyond them, and that can hurt, or worse.
I bought this book many years ago and I highly recommend it:
Motorcycle Design & Technology: How and Why by Gaetano Cocco
Hey AWi Co maybe you should send a copy of this book to Harley Davidson .. I don't think they have it figured out yet.
When an Italian engineer writes a book about motorcycle handling you know it'll be good.
I read most reviews, depending on what edition you buy, it's not obvious if the later
edition is much improved over the earlier edition, the earlier edition appears a complete
nightmare , horrible Italian to English translation, poor math, and very poor editing in general.
Looks like some people loved it ,and others found it a waste of time , trying to figure out
where the poor translations vs bad math and editing start and finish. :shrugs: , I''ll pass, will
look for something else, but glad to know there are books out there that explain bike geometry.
2:26 "the numbers, mason! What do they mean ?!" (I dont know if someone else wrote this or something similar)
fantastic video. It's a RSV though, not a RSV4 ;)
Was looking for this comment! I own a V-twin RSV like this :)
Rsv1000r
RSV 1000 R Factory model too. I know this, because Mike is using a toy model of the life size one sitting in my garage :-)
2:25 Me, even after watching the entire video 😣
Right. Not even a lot of mechanics out there fully understand this too so you can even pay someone to help unless you really want to pay top dollar for someone's time. I'd rather not ruin my bike.
I'm currently doing a study about motorcycle suspension and some dynamics and this video has summarized a big part of a few books that I've read, which were kind of hard to understand. Thanks for making this, made it really easy to understand, props for that.
Check out Tony Foal. 👍
If I increase the rear ride height the bike will become more agile right? Since the trail will decrease and swingarm angle will increase...
Not to be that guy, but something missing on the anti-squat portion is the fact that under acceleration the rear ride height of the bike actually increases not decreases which is counter intuitive. This is doe to the torque vector of the drive chain acting on the axle which sits below the pivot point of the swing arm and the drive sprocket. Or in other words, the drive sprocket is trying to pull the rear wheel to the engine through the shortest distance which is under the bike. If the axis of rotation of the swing arm and drive sprocket were co linear or the rear axle where positioned above the pivot point of the swing arm than the opposite effect would occur. This is one of the reasons why power must be applied smoothly when exiting a corning. To much throttle will shift the CG forward and up. Once rear traction is lost the rear immediately drops until it regains traction at which point the suspension violently extends and draws the rear wheel back into alignment with the front resulting in a high side.
.
thank you very much until now i was very skeptical about the acceleration in a turn subject
Much appreciated the effort!!
- ... traction wasn't mentioned, would a bike with a lower swing arm angle (more parallel) create more traction on acceleration because the pulling force is more lateral? The initial power would be *into the swing arm, as opposed to *perpendicular to a more vertical set up... So the question is, does traction come from more resistance (low swingarm angle) or less resistance (high swingarm angle) where weight, engine, rider, etc are all equal? I guess I should read the book.
The trade off is obviously trail length on the accommodated design? That why cruisers are as they are..?
I should read the book. Any hints welcome. Thank you.
Makanya motor-motor kustom bule enak-enak, ginian pake diitung juga :"(
i cant be the only one who actually understood what he said as he said it.
mechanics isn't that difficult. the important thing is understanding the jargon.
at least he didn't drone on about calculus equations.
I've been following you for a while. Your quality has been getting better and better!!
Great video in general, but the part around lean angle and COG is maybe a bit misleading. Lean angle only becomes dependent COG location when combined with wide tyres (e.g. sports bikes) because the tyre contact patch moves away from the center line of the bike when you corner. For something on skinny tyres the location of COG has negligible impact on the lean angle required for a given speed.
Nice videos mike!! I spent endless nights thinking and reading and searching for all these technical issues and details. Is nice to watch them all in one video. One point still not clear to me is the effect of the height of the neck (steering head) from the ground since is very different between bikes of same category. Seems important to me
I had to stop half way because my head started hurting. Will watch again tomorrow ;)
Me too.
“The use of wide tyres causes another difficulty when the bike rolls because the contact patch moves further and further from the bike’s centreline and from its steering axis. The taller the tyre section the more pronounced these effects are; lower sections minimize them, for a given width of tyre. There are several effects. It reduces the camber thrust for a given angle of lean. Ironically, a bike with a higher centre of gravity or with the centre of gravity shifted in towards the turn, will require less angle of lean to balance its centrifugal force.”
I took that off John Robinson’s book, Motorcycle Tuning Chassis second edition under the section of contact area in tyres.
Perhaps maybe you could do a video why wider tyres need more lean angle to turn and narrow tyres use less. And how how centrifugal force is actually needed to turn with the same bike but different width tyres. Perhaps you can mention why did MotoGP used 16.5 wheels and why some asian drag bikes used bicycle sized wheels on their drag bikes.
Thank you in advance
Hey man, I think you can understand this on a video better than with the words of my. Just search how steering works to youtube and click on some animation.
I don't think you explained that part at the end correctly, it should be like this:
When you brake: TRAIL decreases, SWINGARM ANGLE increases, WHEELBASE decreases (shortens).
When you accelerate: TRAIL increases, SWINGARM ANGLE decreases, WHEELBASE increases (lengthens).
What ? You didn't subscribe yet ?.. Thank you for this very cool and instructive video. Still scratching my head on a few things and on the remark at 9.43. If a lower CoG makes the bike easier to steer in (9.21), then how come a bike with a higher CoG is easier to flicker (9.43) ? I feel like: "Abandon all hope, ye who enter here". I need more neurons... Spare anyone ?
A loot of custom builders especially in USA must immediately watch this video, because some custom bikes are unrideable. Nice educational video
Jhony sins known as teacher, scientist, doctor, etc..so when he explain about bikes, its a best explanation.. 👏👏
Nobody ever crashed from long wheelbase.
NEXT VIDEO : Motorcycle Algebra🤔
Really cool video. In the end a lot depends on the rider's input, obviously right? I liken tag to hitting a baseball and how quickly your mind has to adapt in the moment. I have good experience on all styles of motorcycle. Great information.
That's why different riders have different setups.
This video was for tertiary students. I needed something for primary kids to understand all this
Like everything in the nature - you give to an organizm long legs and compromise on something other, like speed, weight, steering etc
Thanks Mike. Been riding all my life.
When I decided to go track riding on a Sportbike i chose one whose frame is near perfect for me...
2018 Aprilia RSV4 RF LE#14 w/wings!😍
Impressive! Gonna need to watch this a few times though!
Excellent explanations! This information is necessary for both racers and cruisers who want to better their skills by understanding how skills work with the geometry of the bike. Thanks for such a well made video!
Good video, but the concepts are a bit “old”...Trail does nothing, (MotoGP bikes do not have small trails for example) it is just the resulting value of more important things like rake and offset. Higher trail does not mean necessarily more stability if we are talking about different bikes (115 slower to turn than 100), because you can achieve a certain value with infinite combinations (even silly ones). Lower center of gravity does not make a bike more stable in corners, and you confirm this when you say that you need to lean more at a given speed... it is necessary to reduce the leverage that will make the bike tip over during acceleration, that’s the reason why it is lower on sport bikes and why it is lower than the past (less power). And so on. Pay a visit to an Italian site called “Giornale Motori” and look for the tech articles of Federico, a top class engineer, it will explain why a book like the one of Cossalter does look certain thing backwards. Everything starts from CG position and mass distribution on the axes, but it is a long story :)
Such a complicated subject explained perfectly, thankyou! Fantastic presentation too
The centre of gravity heigt don't affects the lean angle, it depends just on weigh/centripetal Force ratio. This depends on the speed and the bending radius, the weigh is uninfluent being either on the numerator and denominator of the fraction. This way it erases itself per each given weigh.... So the lean angle is independant by weigh and just depends on speed and radius...
you're not totally wrong, just stuck in a too simple model of a bike. look at this you'll understand it:
s3.amazonaws.com/advrider-photobucket-images/images/d/dealershipids_cg2_zps3dd45ac3.jpg
More of such informative videos please!
Easy to understand, thank you! Curious if your able to send a link to where you purchased your RSV model?
no. 1k likes!
this video give me so much information ..
i used to thought 'setup' is just the suspension settings
all i wanted to know is where did you got those model bikes
me too lol...I'd like to start honing my motogp skills , seriously though would love to find some of those.
I'm PERFECT at understanding your video. Because I have virtually 0 experience riding a bike
I don't even know what the component's names are, much less how they function.
Thus, saying "what" they do will be use ....... to memorize (not understand).
The difference between viewers who understand based on _your words_ vs _their intuition_ ... depend on understanding _both how and why._
Both are necessary. Neither are sufficient.
When you say raising the bars in the triple clamp means lowering them, people who've never "adjusted triple bars" should become certain of one thing: We don't know what you're talking about. I know; I'll watch someone else's video to understand the principle you're explaining. Wait; is that not your goal..?
I'll try with pool hoping it's something I understand that you may not (though you probably will as M.E. are going to understand vectors, rotational inertia, friction and converting linear force for the cue balls combined rotational + linear moment.
Inside english will kill the cue ball providing you a larger margins of error in certain instances where being on one half the table is sufficient.
Jacking up allows you to jump over and clear an edge of a ball pretty easily (by deflecting it off the table).
You can not only jump over cue ball obstructions, but even jump an object ball over an impeding object ball (with the right angle & power).
Outside lets you cut a ball despite the humidity, inter-ball friction enough to mitigate the value of cut-induced-throw.
Using a thinner shaft will deflect the cue ball less when using side-spin, but, you'll always need to use the exact right offset to compensate for both deflection and the coriolis to pocket balls if the speed is low enough to allow some angular momentum to swerve the cue ball. You can pocket a ball with almost any amount of misalignment (where your feet are relative to your stroke) causing a 'tip-offset' to spin (and deflect) the cue ball ... provided you hit the ball hard enough to minimize the coriolis WITH accurate understanding of the fullness of hit required on the object ball given the type of spin used and the distance from the object ball to the pocket. Likewise, you could also primarily rely on swerve (coriolis) despite not being aligned to pocket the ball; instead relying on the cue ball swerving back across the deflected line (crossing the straight-line path). It will however, require a tremendous amount more visualization & MUCH better feel for the humidity, friction between the balls, the chalk ... and even then, should be limited to balls very close to the pocket which are obstruct by another ball, ,in which jumping it would require getting it up, down, and then not bouncing off the table ... requiring an even higher jump angle (which precludes your head from as naturally seeing the path the cue ball will take. Also, hitting the object ball above the equator magnifies errors because it's essentially a smaller ball ... which makes each millimeter correspond to greater changes in minutes and seconds of angle.
Every statements was true, accurate and would be immediately understood by any pool player as such.
I wouldn't count on someone who wasn't a pool player understanding any of them though, (unless they already did). Is that still teaching?
To know if say, a book I wanted to write were effective, I'd ask people who were incompetent, didn't understand principles, etc., but who wanted to (as in, clicked on your video) if they could explain the principle to me before (confirm they didn't know) and after watching (to ensure my concept was communicated). If they don't, maybe it made sense to me...and would to others _who already knew,_ ... but wouldn't to those who _didn't (or didn't well) already understand.
A big thing that many newbies over look is rear axle position..
Pushing the axle further to the rear will make the bike turn in slower and the moving it forward will make it turn in quicker without even touching the front forks. So try to find the optimal axle length position and if you want to change gearing use different lenght chains to keep it in the sweet spot the rear of a motorcycle is often overlooked but very important for optimal suspension settings
i love the professionality with the colored lights in the background xD
For people that aren't familiar, move the toy bikes according to what you're explaining.
I've been reading the same book in the video "Motorcycle Dynamics" by Vittore Cossalter.
It's a fucking pain in the ass to read, and I'm pretty sure it's wrong on multiple points. Really not recommended.
4:38 how do you set up that camera with stabilizer on bike tank
Very interesting! Great explanation!
I think I'm ready to build a motorcycle from scratch now...
Sometimes i just say f#ck it and ride. This is one of those times.
Thank you for this information brother. Love from #Sikkim
Super job, Mike. Reading the transcript is a great help to really digesting all this.
Well that's an RSV1000, not RSV4.. But I guess it doesn't change the value of the information :)
Great video! But one question:
Are you sure the bike with lower center gravity need more lean angle for a given speed?
Where can I get those scale models?
Awesome vid mate! First I've seen of yours and hitting the sub, keep up the good work
So, swingarm angle increases when accelerating and braking? 🤔
So how the geometry of my 2021 Tracer 9 GT will change when i put a 180/60 rear tyre (instead of 180/55 stock)? And how will affect (fast turning? less stable on top speed? smaller caster angle?) my ride?
good comprehensive video, the model of the aprilia you have is not a rsv4 tho, its a aprilia rsv1000 2005-2009 (3rd gen) model.. I own a factory edition of the 2nd gen myself, amazing bikes
Hi. Interesting and well explained for someone who wants to approach bike setup. There's a part though where I think you probably said something not exactly right, and it's about @ 10:15 where you say that, under braking, trail decreases.
My understanding is that trail is a function of the steering angle, offset and tyre diameter and that the fork length (unless you have a raked fork) is not a factor.
It is theoretically true that the tyre compresses under braking thus reducing the diameter and affecting the trail, but it's compensated by the fact that the contact patch gets wider (mechanical trail, etc.).
Regardless, as I said, well done and nicely put.
Ciao
Yeah, I was thinking the same.
I understand you reasoning, but when breaking hard, the rear lifts and the fork angle changes giving momentarily less trail. Of course, this is compensated by the tyre compression, resulting in more contact surface but less gyroscopic effect. I'm not a mechanical engineer but that's my understanding of that specific moment. Cheers from 🇵🇹✌️
steering angle changes when the fork is compressed
Load the front when making a turn...it helps
Great video as always. Was wondering where your videos were 😂😅 keep producing bro
Geometry books would be hard to understand even for an engineer? Who do you think likely wrote the book? Who do you think designs motorcycles? Engineers. You make mc geometry sound like it's more difficult to understand than particle physics or includes some amount of philosophy. Motorcycle geometry is pretty basic stuff. Common sense to some. And you used the term laymen. What are you? A particle physicist philosopher?
Steering dampers aren't only for bikes with aggressive trail, they're also for off road applications such as a Baja race bike where rider fatigue comes into play.
You should do a video on the BMW coaxial traction system. This is where they put the drive sprocket on the same axis as the swingarm pivot. They learned a lot about chain tension and it's effect on traction because with that deign, the chain tension remains the same throughout the whole rear suspension travel. You'd do a much better job at that than me..and I think it would be a great video! Do it!
1:29 “It will also make the motorcycle *less stable* and, potentially, harder to control.”
What exactly does “less stable” mean? I’ve heard this phrase thrown out a lot when talking about changing your motorcycle suspension. But I’ve never heard anyone explain what it actually is.
Does it mean your bike will randomly wobble at certain speeds and cause an accident? Does it mean the bike will fall to the side on a whim during riding unless you’re always holding the handlebars really tight? Will the bike just stop suddenly and make the rider fly off the road? Or will the bike jump into incoming traffic if you hit a minor bump on the road?
What exactly do you mean by “less stable”?
I would be interested in seeing your analysis of BMW telelever parameter set up!
Hey man, really helpful video
I guess you got a Little mixed up in the start related to trail and cg relationship
And in the end how during acc the WB will increase due to decrease in swingarm angle which gives stability
The trail part maybe I didn't understand correctly.
Can I get your mail or whatsapp no.
I could learn a lot from you.
Thanks in advance
How comes you don't have more subscribers? The quality of this video and it's technical content is amazing. Congrats and thanks for sharing!
Just touching on the Marquez magic....the Rossi wonder...the....😏😳😂😎
Thanks for sharing knowledge about Motorcycle Geometry..Person who wants to learn about VD related to Motorcycle should watch this Video.....
"over and out" "over" signals your done talking. its now the other guys turn to say something. "out" means your signing off the radio.... so correct speak would sound like. (CALL SIGN) STANDING BY ON CHANNEL ONE SIX OUT".
I have a problem with my ZX-6R where it feels like the geometry is constantly changing.
One week when I'm riding at a given speed (±70kmh/45mph), the bike feels great, it's responsive and stable, light & easy to lean in and change direction.
A week or two later, riding at the same speed, it feels like the opposite.
Unstable (head-shaking), poor handling feedback (steering feels lazy and "delayed" almost.)
It requires more effort on the bars to change direction.
The suspension also doesn't feel consistent. Sometimes it feels stiff and other times it feels too soft, even though the preload and damper settings have not been changed
Does anyone know what could be causing this? I've had my front and rear spring rates increased to match my weight, and I've had my sag set correctly as well.
I don't know what to do anymore.
There is a ratio between trail and forks angle. And spring rate characteristics contributing to bike geometry while suspension is loaded mid-turn with cornering force.
Awesome video.
Please tell me where can I buy these model bikes? Especially the RSV.
Wow, that was a really great explanation.
I thought it was jhonny sins.
Sry dude..
Tire-width combined with weight is determining speed at given angle in turn. THEREFOR is a Motard, weighing 120 kilos on a 160 section tire, much faster mid-corner than a 200 kilo sportbike on 200-section tire.It is the offset of center of gravity and contact-patch that determins centrifugal power in addition to speed and angle.
I never understood why some guys like to extend the forks on their motorcycles to ridiculous angles (i.e., Easy Rider/“choppers”). I guess it is a ‘statement’ of rebellion or something along those lines. But to me those “choppers” look stupid, and the clowns that ride them are definitely making a statement about themselves.
It would make for great comedy to watch the Hells Angels vs. The Mongols vs. Brother Speed vs. The Bandidos, etc.... in a Grand Prix style road race on their choppers. The wrecks would be outrageously entertaining along with the fights that would ensue shortly thereafter.
Need help. It hurt my brain trying to make sense out of it. In my common sense, low ground clearance = low CoG = (+) stability. That though makes sense in a straight, right?
I increase both tyres size in 1:1 ratio. I experience a significant head shake in straight line, scared the shit out of me. So my point is. If you move fork tube up it will decrease trail and vice versa. Doesn't higher ride high make it less stable? Or the consept completely whoosh me.
Is the length should be changed when rear tyre exchanged from 180/55-17 to 180/60-17 or 190/55-17 ？ And why?
That’s a long way of saying “yet again, Harley has spent time and money to produce lots of noise while being one of the poorest handling and performing motorcycles”.
But they do go blubblopblapbrapblopblupblop. Cue South Park noises.
Just a quick feedback: Less music while you're explaining these concepts would help, since English isn't my first language. thank you in advance
Small issue with trail making it possible for a bike to stay upright. Experiments have shown that even reversing the trail doesn’t cause the bike to become unridable. Obviously it’s complicated but in short a bike 🚴 or 🏍️ will continue to do its thing with some pretty radical departures from conventional design. Sure that will cause things to function in a less than ideal way, but they still function.
What brand are these models from? The Aprilia RSV one looks especially juicy!
You're mentioning @10:14 when the rider brakes (decelerates) the swingarm angle increases however @ 10:50 while the rider accelerates, the swingarm angle ALSO increases which doesn't make any sense, could you explain how?
Somethings you didn't mention is gyroscopic effect, unsprung weight, spring rates and dampening all very much apart of the steering, stability discussion, peace...
Another excellent episode
How does front swing arms change geometry? Does it make the bike more stable?
As a visitor, your trail explanation make no sense, what do you measure and where? The lines you draw are just hanging... 10x...
Very informative but the distracting, obnoxious background music made me vow never to come back to your channel.
The subtitles look so off :/. Good explanatory video, though.
Gotcha well!
I've been sending people to watch this video many times, but on today I was searching for something, heard the phrase on 6:15 and wondered - how actual load transfer is related to suspension travel? :) Not sure that it's correct to state that anti-squat helps with load transfer...
Can somebody explain how does rake/wheelbase decrease upon braking?
TLDR buying a GSXR600 as my first bike, good or not? :D
The rear does not squat under acceleration like a car. The rear seat goes UP due to the tension of the chain being turned by the engine.
there's some wrong ..you show moving up forks and lowering the front of the bike . but this only modification don't lowers the back like you do on the model ! .. and dont makes a smaller anti squad angle !
Mx rider here. So bigger offset triple clamps decreases trail which in theory would make the bikes more agile/less stable. Then why in real world effect does more offset seem to make the bike more stable. It is very common on motocross bikes for riders to change from 22mm offset clamps to 24mm clamps to get a more stable ride. Is this effect due to the lengthening of the wheel base?
Don’t know why you are being downvoted? Loved the information and the format. Thank you!
What brand and scale of motorcycle models are you using for your video? Great video, thanks.
Regarding trail: This is also relative to speed. An off-road bike can live with a longer trail because of the lower speeds, lower weight, and lower weight of the engine internals, and thus the lower gyroscopic effect.
In regards anti squat: Motorcycles with swing arms - shaft driven even more than chain driven - have a natural anti squat tendency.
In regards to centre of gravity: This can't be isolated to the bike alone, because it's very dependable on the mass of the rider. And the movement of the rider/the second chassis.
The centres not afflicted in the same way by the rider is the geometric centers, like pitch, dive, squat etc, tough the riders moving mass will affect the behaviour.
It's easily doable to make a bike anti dive, regardless of rider weight.
Or am I completely off the mark?
[Edit: Funny typo :)]
Ah yes - the "lover gyroscopic effect". Let me imagine that...
@@anthonyefarr :) Less rotating mass, or less inertia? What would be the correct phrase? I could of course write it in my own language, but on the world stage that language don't seem to fly ;)
Thank you for your video. These things work until you don’t talk about telelever and other like suspension 😂
You promised that by the end of this video these terms will start making more sense to us... Now that the terms make sense I know I know nothing. Sgt. Shultz.
This Aprilia rsv4 model looks so great but i can´t find a website to buy it. Does anyone know better?
good vid, one ambiguity at 10:58. You mention a decrease in wheelbase as weight transfers to the rear but comment that this adds to stability, which contradicts the correct point you made earlier in the video re wheelbase. Sure its only one factor in play at that point but just sayin....