Join Date: May 2017
Location: Northern Ontario Canada
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Shims vs Coop45
My general observations with shims vs Coop45 machined sheave. Hopefully this will help others understand the effects these mods have on their machines before making their decision on what mod is best for them. Results may vary based on numerous variables. Belt and sheave condition greatly influences the final numbers.
2.65 to 2.70:1
Aprox 8-10% reduction in initial ratio, around 2.5 mph top speed loss
2.75 to 2.8:1
Aprox 12-14% ratio reduction, around 4 mph top speed loss
-Coop45 sheave, no shim
Aprox 18.5% ratio reduction, equivalent to 2mm of shims but no top speed loss
-Coop45 sheave, with 0.5mm shim
Aprox 22.5% ratio reduction, equivalent to 2.5mm worth of shims but with only 1.25 mph top speed loss.
Anyone else feel free to post your own results
2009 Grizzly 550 Special Edition, Red Midnight Armour, EPS, 26"Pitbull Growler BG2.5 xor, on 12"polished alloy SE wheels with 1"spacers, Yamaha overfenders & windshield, Heat Demon grips & thumb warmers, 2500lbs Warn winch, two up seat / storage box, Moose rear bumper, Gold Plugs in diffs & engine, Pod Mod set to 45, COOP45 machined sheave + 0.5 shim (3.1:1), 18 gram weights, EPI Orange spring
Last edited by Vincent; 08-18-2018 at 10:03 AM.