Load Transfer On Acceleration/deceleration.question For Keith.

[Kalkat]

Keith,

I got into an argument with a racer friend over whether load transfers front or back when you accelerate. I was VERY positive that load transfers back when you accelerate, and forward when you brake/decelerate.

 

My friend thought it was the other way around. and he said he read so in TOTW, so i decided to go home and check myself.

 

Wat i found was funny, and confusing. At numeroous places, Keith talked about loading the back by accelerating ( one such instance was chapter 10, page 81, in TOTW).

 

but then, in TOTW II, chapter 3, i found a mention where Keith says that the rear will RISE when you accelerate!!!!! and gave the same eg that my friend had given me, of puttin the front against a wall and rolling on throttle and seeing that its the rear that rises!

 

NOw, this is pretty confusing. If the weight shifts back when you get on gas, then how can the rear rise? I am sure the mere mortal me would be mssing something, but would you mind explaining Keith?

 

Thanks!

 

oops, plz move it to 'setup and handling' if this is the wrong forum. apologies.

[racer]

Hi Kalkat,

 

I know I'm not Keith (I'm much younger and better looking) but this subject has been discussed at great length here.

 

There is a search function you can use to find the thread(s) or you can scan down the thread titles, too.

 

In any case, in a nutshell, weight (bias) transfers to the rear under acceleration.

 

However, due to the triangular relationship, that is to say the angle of the swingarm to the chainpull and the position of the swingarm pivot above the chain, the chain pull crosses the swingarm and pulls DOWN on the rear of the swingarm in an arc as the arm rotates around the pivot in the frame.

 

Try this:

 

Draw two circles to represent the front and rear sprockets.

 

Draw a line acros the top of the two circles to represent the top (pull) of the drive chain.

 

Now draw a big dot above that line to represent the swingarm pivot and a line between that big dot and the rear sproket to represent the swingarm.

 

Imagine the chain pulling forward under acceleration.

 

What happens?

 

Racer

[Kalkat]

searched and got my answer. thanks!