A friend of mine suggested I put a 34 tooth pully on my transmission.
What do y'all think?
Pros Cons?

 

What all are you running? Compensator/ basket and rear pulley? what trans? And what is your goal for ratio. Rpm/ mph? A 34 could really lug what you currently have especially if it's still a stock set up.

 

All pullys and sprockets are stock.
Motor has 9.5-1 pistons, .030 head gaskets, EV-27 cam.

 

What year and model is your ride..

 

95' Heritage.

 

You would be going from a 2.92 overall ratio a 2.75 Which will probably drop it about 400 rpm at cruising. I might be a little off on the conversion of 400. But I think that would be to low. What are you pulling at 60 mph and 70 mph?

 

I wouldn't fool with that. The factory probably got that right from the start.

 

Correction....if your running a 130/90/16 the approximate diameter is 25.7" so at a 2.92 ratio (32 tooth stock) at 70 you should be pulling around 2670 rpm and at 2.74 (34 tooth) 2516 rpm.not to much lugging I guess. But at 60 it would be little to low as 2142 rpm so for 55 mph your definitely gonna need 4 th gear....especially with that 27 cam.....

 

So basically it is only a difference of 150 rpm?

Doesn't sound worth it to me.

 

Our Evos are all over-geared as stock IMHO, the poor things don't need even higher gearing! A 34T will lower top gear revs by 32/34 = 0.94, so from 2,500rpm you will drop to 2,500 x 0.94 = 2,352rpm, a change of 148rpm.