Motorcycle Racing Forum

Racing Discussion => Racing Discussion => Topic started by: xseal on July 03, 2004, 11:47:48 AM

Title: Equivalent gear ratios
Post by: xseal on July 03, 2004, 11:47:48 AM
So, I'm due for a new chain and sprockets, here is my qusestion: Which of the following gearing sets is preferred (understanding that they are the same final ratio)?
- 14 / 41
- 15 / 44

Does it really not matter at all, or is there some benefit to using generally larger or smaller sprockets?
Title: Re: Equivalent gear ratios
Post by: cardzilla on July 03, 2004, 04:40:38 PM
There are really only two considerations, weight and wheelbase.  Weight is really not a concern unless you are really nitpicking.  Wheelbase, however, is.  The smaller rear sprocket will equate to a longer wheelbase and the larger sprocket to a shorter wheelbase.  The difference isn't huge but at some tracks it will make a difference (talladega GP comes to mind).  Hope this helps.
Title: Re: Equivalent gear ratios
Post by: Eric Kelcher on July 03, 2004, 05:45:07 PM
generally you want the larger sprockets as the chain does not have to flex as much and the pull is straighter and lends it itself to less squat and rubbing on the swingarm.

The wheelbase is a second consideration and depending on the bike one may out way the other.
Title: Re: Equivalent gear ratios
Post by: xseal on July 04, 2004, 09:27:21 AM
yes, but if I'm getting ready to change out the sprockets and chain, I'll just be altering the chain length for whichever set up, so the wheel base should be the same w/ a new chain. I'll go with the biggers sprockets, thanks.
Title: Re: Equivalent gear ratios
Post by: Super Dave on July 10, 2004, 06:28:51 AM
Chain and sprocket changes will effect anti-squat.

I use gearing changes to alter more important things like front end geometry...specifically trail being the most important.

As the rear axle moves in the swingarm, the wheel base changes, but more importantly, the swingarm pivot location is altered.  This effects front end geometry.

And this is what we cover in my racer university and independent programs.