30 tooth pully vs. 32tooth

[ridinrigid]

Getting ready to change trans pulley on my 03' flhri to a 30 tooth . Stock 88 motor could use some help with the Frankenstein conversion .I'm assuming the stock 139 tooth belt will be to long,and I'll not have enough adjustment available. Is there a formula to figure belt length ? Would reducing belt teeth by 2:1 per tooth reduction of pulley teeth work ? Got all the new seals , new pulley and tools to make the swap and would like to have the correct belt on hand to avoid reassembly delays.

 

[captdanwh]

i am not sure you will need to change the belt at all. after changing my sprocket from a 32 to a 30 tooth i did not have to change the belt. unfortunately i do not have the same kit as yours so i do not know how much slack adjustment you have , the champion kit had plenty. i would change the sprocket first and see if the stock belt will work or if it is to long. i have never heard of somebody having to go more than a 2 tooth smaller belt on any conversion but belts are expensive so i would wait and see if you need a new one before ordering one. you can try calling Frankenstein and see if they know, they should.

 

[THEREALTRIKKY]

If I were you, I'd talk to the folks @ Frankenstein.. See how much adjustment beyond OEM their belt adjusters allow.. Also, take a look at where you're currently sitting as far as belt adjustment goes. If the adjusters are 3/4 of the way to full rear, you probably don't have enough adjustment left. If you're to the front, you'll probably be just fine...

 

[Shriner Jim]

I changed my 2008 from a 32 to a 30. It made a world of difference. I did not have to change the belt. All is well.