[shawnm]

on my indy trail 488 fc i like to get her to rev out a few more rpms right now she reving at 7000 could i get another 500 or so on this engine what could i do to get this engine to rev around 7500 rpm.

 

[Boss302man]

tightening the secondary spring a hole or two will help a little. Do you have the stock clutching and gearing?

 

[Felix the Cat]

if polaris clutches are anything like cat's, i wouldn't try to get 500rpms by moving the secondary spring.
either use a primary spring with a higher finish force, lighter flyweights or helix with less finish angle. perferably use one of the first two choices.

 

[xcr440]

For each hole move you get about 250-300 rpm. And it makes it back shift faster.

 

[shawnm]

i got stock gearing in it right now origanal clutches secandary spring is red in the second last hole with a 36 degree angle also got a 34 on my bench from an indy 400.in the primary i have a black spring with a-2 weights but i got a-1 weights that are notched would they be any good.it seems to work best with the 36 degree angle and seem the best with the stock gearing .i tryied different gears but the stock ones seem to be the best so if i try the lighter weights what should happen from low to mid and top end to me clutching can be a confusion thing you can change varitions for hours and days to try to get it perfect.even if someone had an indy 488 fan with the clutching done can give me some feedback on what they have done would be great thanks.