Re-tuning the clutch because of that damn Ultimax3 belt explosion

bluemonster1

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Since I expoded that stupid belt,I had to put on my spare belt..the OEM one.Good thing I didn't use the Utimax3 for a spare.What cheap piece of crap.Was running good rpm's for a while with it.With OEM belt my launch and WOT rpm's climbed 500 rpm.Now launches at 8600 and WOT at 9000.
Using 8DN-20 weights with no rivet inner and 2.7 outer right now.Using 14.5mm rollers instead of those 15.6mm rollers.Wrapped at 70 in secondary.What rivets should I use to drop rpm's to launch at 8200 and WOT at 8500.Here I go again.
 
Turk you were right again,that stupid belt didn't last long.Like one good hour today.LOL.Since I put my OEM belt back on and 14.5mm rollers back,I am now launching at 8600 and WOT is 9000. What is your formula for getting this back to normal values.
 

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Here's my first try at set up in clutches with 8DN belt today:

Put 3.6 g in inner holes
Put 3.6 g in outer holes
Wrap is at 70 in secondary
Belt is 8DN (OEM)


RESULTS AS AS FOLLOWS:

At launch seems to be at 8200 rpm
At WOT seems to climb to 8400 rpm

If I replace outers with 3.1 g that's a total of 1.5 grams less.
It took 2.7 gram increase to drop it 500 rpm.
So 1.5 gram increase may take it up to around 8600-nearly 8700
It is a fine line.Could end up drilling thru the outer 3.6 g rivet with small drill bit on drill press thru the centre to lighten the rivet.This would slightly raise the rpm maybe to 8500.
 


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