Originally Posted by yagerzzz

Listen to Jack. He knows his stuff! One tiny correction though. The 25 on the rear will actually be slightly faster than a 26 on the rear. As Jack said, bigger on rear means slower, so naturally smaller on the rear means faster.

Just divide the number of teeth on the front over the number of teeth on the back. The larger the fraction, the faster it's geared. The '87 and '88 model with the 428 chains from the factory were actually geared ever so slightly faster, but probably not enough to be noticeable.

'87 & '88: 12/26 gearing = 0.461538 final drive ratio
'89 & later: 10/22 gearing = 0.454545 final drive ratio

By running a 13/25 combo, your final drive ratio will be 0.52. That will actually be a noticeable difference.






As an FYI, I'm getting ready to run a 14/26 combo (0.538462 ratio). I wouldn't recommend gearing them up this high normally, but I'm going to be running a little smaller rear race tire, and I've got a motor that SCREAMS. Somehow, it seems to have Moore power that most other LT80's.