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At 08:54 AM 12/21/2008, you wrote:

When I did this to my Superhawk it was an accident ( I cut the chain to the stock length before I realized I was adding three teeth to the program). I inquired with a few local buddies with more experience than myself, and was told if it fits, it's OK, and will shorten the wheelbase, but exactly as you said " we are not good enough riders to notice" the difference. Well, riding ability or lack thereof not with standing, the difference on my Superhawk was close to an inch, and very perceptible. So in an effort to make the RS more flickable, I thought I would do the same thing...


Yeah, 118 links (or whatever your stock length chain is), is a fixed length until it is worn. Now bikes have enough adjustment that you can move the rear axle enough to resolve the changes in length that changing sprocket teeth counts will create. Some won't, since their adjusters don't allow that much movement. My RC51 had the rear axle just about hanging off the bike, I assumed the PO had screwed around with the sprockets and not properly calculated the chain length. It did not really matter to me at time since Romeo-Charlie-Five-One was plenty rough, and needed quite a bit more than just a chain and sprocket set.
But when I got into it, I found the chain setup was down right scary.
First the front sprocket was down two teeth (it was also not the correct sprocket for the RC, with washers acting as spacers to keep it aligned with the rear!), and the rear was up two teeth. That got me looking at the chain that was on the bike, here the PO had added four links. I don't know how he rode it.
I put it back to stock gearing and ended up having to flip the adjuster blocks to allow the axle to move forward enough to have proper tension. Now the bike was handling much, much, better.
Okay it is still handling like sh!t, but the problem is now the bike can turn and does so very well until the mismatched, wrong size and just plain junk tires start to slide. I know that the bike can be sorted with some good rubber on it (Hear That Santa!!!) and made to handle like it really can.

I started thinking a lot about how little the customers at the parts counter know about chains and how they should count teeth.

There are a few simple rules:
1. Anytime you go up or down more than a tooth, you should plan on using a non stock chain length. However only take out/add in an even number of links. In other words if you went up three in the rear only add two links to the count on the chain. If you went down four in the rear then take out four links. Again, one up or down on either end of the bike is not going to be that critical.
2. Don't assume that the bike is stock at both ends, especially if you are going to change the sprockets to something other than stock counts. I had a customer bought his bike new at another local shop, and had them "hop it up" before he took delivery (it had a TBR pipe, pc III, zg double bubble and a couple more bits). He wanted to go down Three in the rear so that it would wheelie at the drop of a hat and be ready to stunt. Only when we actually looked at his bike did we discover that some genius at the other dealer had already gone up two teeth in the rear.
3. just like a slightly dropping the triple tree down the fork tubes will make a big difference with the way the bike handles, so will moving the rear axle fore or aft in the swing arm (not to mention the up and down with an eccentric adjuster.

A Dragon Ascending
"Forging my body in the Fires of my Will"

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