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To sheave or not?

1149 Views 4 Replies 4 Participants Last post by  Grizzach
I currently have 28" zillas, big gun fuel controller, modified exhaust end cap, rad relocator, 1.5 mm shim mod and purple epi spring, wet clutch slugs. Is it worth the money to put a machined sheave on? Are the gains noticeable? Might upgrade to 30" zillas or silverbacks.
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Yes and No...
If you're a mudder and don't care about top end loss or trail riding then have what you need. Depending on your machine you might be able to install more shims.

A Coop style face machined sheave gives you the low end torque without top end loss. Getting 3:1 ratio is common.

Channel machining like Hunterworks extends the roller weight ramp travel. This type of machine has a little problem with roller flop and reaching the 3:1. The machinist needs to machine both ends of the ramp to save the top end.
Im running a .5 shim, jbs extreme sheave,
18gram sliders, bullet box, home made ehs lid and black path exhuast tip with 30 zillas. Great setup very pleased. Wheelies easily, rides like a couch. Does rub sometimes on black mud flap area during full compression but not bad and nothing solid. Love the 30s but hate the rubbing. No lift. Probably 28 zillas are the sweet spot but i cant go smaller now...
If you send your sheave to james at jbs he can mill it for cheaper than buying one from him that is already milled. My ratio is over 3:1. But youll have more down time while you wait for him to do the work and send it back. Ive had it up to 63 according to the speedo. The over sized tires make it read lower so it was probably around 67 mph but even 63 is plenty for me.
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