How Does Suspension Squat Affect Motorcycle Handling?

Automobiles squat when they accelerate. If a motorcycle squats when it accelerates, that’s a problem.
Motorcycle rear suspension is different from automobile suspension in one important respect: When an automobile accelerates, it squats in the back because weight is being transferred from the front to the rear as a result of the tires pushing the vehicle forward at ground level while the mass of the vehicle is above it. That tends to tip the vehicle to the rear.
If a motorcycle were to squat down in the rear as you began to accelerate off a corner, that would take weight off the front, which would not steer as well as before-you would try to steer into the turn and the bike would drift to the outside. When you came into the pits at the end of practice, you would be asking your crew chief for a solution.
The force that opposes squat in a correctly designed motorcycle comes mainly from the drive chain, which is not parallel to the swingarm’s central plane but at an angle to it. And the tangent of that angle determines an anti-squat force. When you hear that a certain sportbike has an adjustable swingarm pivot height, it is at this problem that feature is aimed.
By varying the height of the pivot and therefore the droop angle of the swingarm, you alter the angle between the chain when it’s tight and the swingarm itself, thereby changing this anti-squat force. When that force is able to completely balance the weight shift caused by acceleration, you can accelerate off the corner without squat and push.
Read the full article here: www.cycleworld.com/how-does-s...
Check out more Ask Kevin Features: www.cycleworld.com/blogs/ask-...
Subscribe to Cycle World KZbin: kzbin.info?s...
Read more from Cycle World: www.cycleworld.com/
Buy Cycle World Merch: teespring.com/stores/cycleworld

[@2fastnlight]

Please keep asking him questions, gold mine of understanding

[@mikefrench616]

Not only does he understand it but he can explain it so clearly and so quickly. I always read Kevin's articles first, have for alot of years. Then I look for Peter Egan.

[@paulocarreiro5855]

It's not just what he says; it's the way he says it! The man is a video star! Again, the editing (music included) is brilliant.

[@bigcheese781]

Why anyone would dislike this explanation is beyond me. It's just as accurate and precise as you'd expect.

[@jimjames8234]

Raise your hand if, you could listen to Kevin explain shit forever....

[@alderinerush]

Never thought about sprocket size effecting squat.

[@dreamwhileyousleep]

Keep these coming!!! How about a "What's in Kevin's Garage" episode?

[@db3170]

Polaris addressed this with "Concentric Drive" on there 99 and up chain driven atvs. Brilliant! .

[@Shastar271828]

Thank you for posting these truly informative videos! The explanations are superb! Learning quite a lot from these.

[@Rlindagem]

Great video.

[@cyclopathic998]

How about Horst link? It was originally designed for motorcycles but was abandoned as it eliminated squad completely.

[@mohba01]

Hi Kevin, firstly I love your video's and a Big Hi from India. I have some questions regarding off road bikes with respect to the same topic of suspension squat. The physics behind pro squat and anti squat is complicated (and I dont necessarily understand it fully, yet) and most modern dirt bikes have been designed carefully from the factory, so that the squat effects benefit the bikes handling in a positive way, which in a way is quite the opposite of how a road bikes rear geometry works. Apparently, Enduro and dirt bikes have a certain degree of anti-squat during the majority of the suspension travel and it changes to pro squat deeper or later in the travel for rear wheel traction and steering ?? Obviously, The relationship between these two is critical to suspension performance and I assume, traction as well. an elaborate explanation or a video on this is highly appreciated! lot of folks have many misconceptions about this and disagree that an Off-road bikes Suspension Squat dont affect Motorcycle Handling... which is obviously false. cheers and thanks in advance.

[@trykozmaksym]

Bare table is enough for true master.

[@UncleWally3]

So, what does Honda's new Goldwing Hossack-style front suspension add (or detract) from handling?

[@MrMedoSmily]

love u man

[@danraymond1253]

So I'm still confused. Are parallel swingarms better or worse than swingarms with a droop angle? I got the impression from the video that they were better, but you said when Honda did it in 1988 their bike squared down out of a turn, which I understood to be a bad thing.

[@MCBCest]

How is anti squat handled in shaft driven bikes?

[@db3170]

See Moto Guzzi V11sport

[@jmm2270]

Not sure if you ever got you answer, but shaft moments are neglected because the force is in the plane of the swing arm. Most shaft driven motorcycles actually lift up in the rear under thrust. This can be countered by implementing a 4-bar linkage shaft coupler.

[@Lasnoe]

So when motorcycles compress the front suspension when increasing throttle on a dyno... Is that due to the built in angles ensuring moving parts of the motorcycle alone also encourage front suspension squat? 🤔

[@kshitijrajput8839]

how do you control anti-squat when there is no drive chain and no gear ratios, i.e, in case of a hub motor (EV).

[@mohba01]

Grip is always mechanical. principles of load transfer will still apply. Electric hub motors tend to be heavy, affecting the Center of Mass and of course, will have unsprung weight characteristics different from traditional motorcycles.

[@Shastar271828]

There is still a swingarm, and the rear wheel still wants to run under the center of the motorcycle, thus shrinking the base of the triangle during acceleration, and lifting up the seat. Maybe the static angle of the swingarm is reduced to account for the lack of chain force?

[@ajv802]

I thought squat lengthens the wheel base. Making it want to run wide when you get on the gas hard out of corners?

[@davidciesielski8251]

I just hope Tony Foley doesn't see this.....

[@akupehsluarketatAR]

A few times i saw on an auto scooter everytime the rider gas it, the rear actually lifted up. Guess its got somethin to do with the swingarm angle

[@roybartran6756]

I had a 1977 xs750 with the drive shaft.....it would stand up in the corners which was most disconcerting.......I think BMW does the same thing........drives shaft are a different animal....

[@tonnysenioranthony4251]

Great video, terrible music