? I'll give you the specs I have for a 2001 600 Edgex. primary spring:dark blue/white, weights: 10-58, Helix: R-11 #2, Secondary spring: silver/blue.
I've got 10-60 weights in mine with the secondary as delivered. You want to keep the revs around 8,000-8,200. On the low side is better. Mine was at about 8,100 when I first went with the 60 gr weights. It is now around 8,300-8,400. Perhaps my secondary is in need of cleaning or my engine is now broke in well and making more power. Either way I'm taking care of it soon.
Stock gearing is 23-39 tooth 74 pitch HYVO chain. You can go 22-39 with stock chain. (what I did) 22-40 will also work with 74P chain and give you 97 MPH with a jackshaft rpm of 8,200.(What I'm doing next year) Keep in mind the clutches are in overdrive when fully shifted. Just watch your tach when really flying. IF it ever fully shifts out you will know it. I had an old 400cc Scorpion that fully shifted @ about 75 mph. Worked for me!
some sleds will start climbing in rpm others may just hold rpm and some come down in rpm, nature of the beast.
what are you looking to get out of your sled? bottom end mid range or top end with trailability?
Well, I've NEVER been on a stock sled that ever fully shifted out. As in run out of gears. Imagine driving your car and not taking it out of first. You will go faster until your engine won't rev any higher. If your gears are to low in your sled what will happen is that while holding the throttle open your clutches will keep your RPM even, at 8200 for example, while shifting into an increasingly higher gear until your clutches have reached their maximum shift at which point any increase in MPH will have to come from increased RPM. In other words your tach will read higher.
I've lowered my gear ratio for acceleration and plan to go lower. If you are looking for flat out speed on a long run I doubt lowering the gear ratio will help. At the same time I wouldn't raise them either. Manufacturers set the gear ratio so that there is no chance you will ever over rev the engine for lack of a higher gear.
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