| Author | Message | ||
     Mgdpublic |
Whenever I read about the suspension rising under acceleration, the explanation is always vague. Typically something about the torque reaction on the rear tire. I suppose it's "throwing" the bike up but can anyone explain it better? Also, many people advocate feathering the rear brake while doing slow speed U-turns. Jerry Palladino says that this makes the motorcycle "think" it's going faster. Lastly, in Total Conrol, Lee Parks advocates decreasing throttle and increasing front braking at the same time to slow down, so you're basically doing both at the same time. He says it settles the suspension, and when I tried it, it certainly did, but I don't know why. Anyone? Thanks! | ||
| Bomber |
briefly, and without a white board, lessening the throttle while increasing the braking action meanas that the transition from accelration to braking is more gradual, and suspensions, generally, react more predictably to gradual changes than abrupt one . . . . . . some bike's rear suspensions give a rise on acceleration due to the angle the swing arm is in relation to the chain (chain pulling forward will create rise, fall, or no change, dependiong on the swing arm angle) . . . .. front suspensions extend under acceleration because of wieght being transfered to the rear of the bike these are great questions, which, sadly, have no easy, simple answers . . . there are a number of books on chassis design that touch on these topics (the one from Apprilia is particularly math laden, if that's your thing) I'm looking forward to the more engineering-talented among us to enter this topic | ||
| M1combat |
Well, I'm not exactly engineering-talented... The rear of the bike raises during acceleration becaus of it's (the swing arm) angle. On the XB the axle is a good deal lower than the rear isolator. Imagine this... You have the tire removed but the axle in place and the suspension is in the same position as it would be if it were sitting on the ground with a rear tire... Now... Push STRAIGHT forward (relative to the ground) on the axle. The axle is lower than the rear isolator (or fulcrum) therefor it attempts to try to move undernieth of it. It raises the rear. Take a piece of paper and put a crease all the way down the middle (doesn't matter which way). Lay that peice of paper so the the crease points up and is running right/left relative to you. Hold the top of the paper in place. Push the bottom away from you. The crease rises? Also, pull straight back... The rear (crease) will lower. Basically, during acceleration, the swingarm attempts to place the axle at the front and during braking the swingarm tries to level itself (moving the axle as far back as it can). edited by M1combat on June 30, 2004 | ||
| Torqd |
M1combat... I didn't know that you are into Origami :-) | ||
| M1combat |
I'm probably more into Origami than suspension dynamics but I try  . |
