Pulley Mod

DB Cutler · Post by **DB Cutler** » Wed May 23, 2007 2:10 pm

Ok, I read some of the posts which are supposed to make a Spree faster. The "pulley mod" refrences describe removing the lip on the inner pulley and replacing it with a washer.

What does this do ? Does it reduce the friction on the drive pulley and therefore allow it to spin more freely ? How does this improve the performance of the engine and does it destroy the power at the lower end of the rpm curve ?

I'm just trying to understand how and why this works since I can't find an explanation that doesn't simply say "It makes your Spree go faster".

Kenny_McCormic · Post by **Kenny_McCormic** » Wed May 23, 2007 3:36 pm

no you shave part of the lip off so the gear ratio changes then you use wahers on he sides of the pully to keep it alinged with the clutch.

DB Cutler · Post by **DB Cutler** » Wed May 23, 2007 4:30 pm

Got it, so by shaving off part of the lip the position of the belt changes vertically within the "V" formed by the inner and outer pulley.

So by making the "V" narrower, you move the ratio between the front and rear pully closer together.

That would require you to spin the engine a little faster to get going, correct ? So the net result would be that the scooter feels like it has less torque but will end up with a higher top speed, correct ?

Farfignugin · Post by **Farfignugin** » Wed May 23, 2007 8:48 pm

not entirely. The clutch would engage at a lower rpm (that is why in the posts they also suggest stiffer clutch springs). So with that, the rear tire would go faster at the same engine speed than without the pully mod.

stillspeeding · Post by **stillspeeding** » Thu May 24, 2007 2:12 am

its real simple- if you want speed start with an engine that can produce speed, then pump some $$$ into it, you can even go low budget with a few tricks

DB Cutler · Post by **DB Cutler** » Thu May 24, 2007 7:30 am

I'm asking because my Spree is used as a pit bike for a racing team. What I really need is more low end torque rather than a higher top speed. So I'm looking for ways to get the scooter to accelerate quicker rather than something which accelerates more slowly but to a higher unltimate velocity.

So would this mod be good for my application ?

chevyguyjay · Post by **chevyguyjay** » Thu May 24, 2007 7:36 am

dump the spree engine, and get a elite SE50, or a dio engine.

DB Cutler · Post by **DB Cutler** » Thu May 24, 2007 8:44 am

Nah, too much money and work. I just want to make what I have run as best as I can until I can afford to get a Honda Ruckus.

PimpinSpree · Post by **PimpinSpree** » Thu May 24, 2007 1:33 pm

it makes you lose low end and gain top speed

DB Cutler · Post by **DB Cutler** » Thu May 24, 2007 1:59 pm

Thanks !!

Kenny_McCormic · Post by **Kenny_McCormic** » Thu May 24, 2007 5:57 pm

if you need better bottom end upgrade the intake and reeds then do the reverse pully mod by putting a washer between the pully halves.

Post by **noiseguy** » Fri May 25, 2007 3:24 am

You'd want to run a thin washer between the pulley halves instead to spread them. Also moves up clutch engagement a bit, which should help low end torque.

DB Cutler · Post by **DB Cutler** » Tue May 29, 2007 1:44 pm

I just got the new clutch parts today so, I'll try the thin washer trick when I put everything back together. Thanks for the tips !!

halfj99 · Post by **halfj99** » Tue May 29, 2007 5:44 pm

sombody should really take pics and write a how to

Farfignugin · Post by **Farfignugin** » Tue May 29, 2007 6:06 pm

I thought they did.