If your not lake racing I would recommend gearing these sleds down a little. In my opinion the old 600 VES motors were overgeared for the conditions I ride in, now spin the motor at a little higher RPM and it's maybe even a little more overgeared. 20-41 and 22-40 will work with your stock chain.
Air box continues to be a concern on this sled. My air box isn't even close to lining up with the air vent in the hood. The problem this is causing is the air box isn't getting all the air capable from the hood vent and in could be choking the motor on long runs. Also, hot air from under the hood could also enter through the hood vent and into the air box. If you position a SLP air box inlet kit correctly it should solve this problem.
Gutted air box with stock air horn removed as well as all internals. Noise doesn't seem to be much louder than stock.
390 main jets (Check wash, jetting and pipe heat are a huge deal on this sled.)
60 pilots, I haven't checked, but I think I've got .8 or .9 air jets in it. Small size air jets seem to clog very easy and the motor runs like a dog when they clog.
Clutching: (This is with air box gutted and a few other tricks, if your sled doesn't have the same stuff done this setup might not work. If you have gutted the air box, matched the carb boots, spec'd the head and most importantly jetted the sled, you should be able to pull this setup.)
10-64 weights
EPI Yellow or EPI maroon Primary
Stock helix and stock secondary spring.
(This motor likes to rev to make power and needs RPM's above approx 7900 to make power)
Carb boots can be matched to carbs for better flow. Be careful as the carb boots aren't very thick in all areas.
Head volume should be close to flat plate 34.5cc's. If they are off most performance shops can cut the head to close to this spec. If anybody has squish specs please let me know as I'd like to get a general concensus comparison.
Weight: 483 lbs.
Jetting: 290-300 mains at approx 65-70 degrees (Pipe heat is a major issue)
Pilots: 75's
Needle #3
CDI: 500 ft. Race program
Top Exh. = 30.5
Btm Exh. = 65
Exh chd width = 51
Aux Exh width = 14
Top Transfers = 50.5
Btm Rear Boost = 66.5
Other Trans btm = 64.75
Bore x stroke = 77.25 x 64
Exhaust Duration Approx. Range = 198.5 - 201
Primary spring: Black/Green
Priamry weights: 10-62 weights
Secondary: Team Roller 64-42/.360
Secondary Spring: LH Rd/Black 140/240
Main Jets:420's
Jet Needle #2
Pilots: 50
Pilot Air Jet: .6
Gearing: 23:39, 76 pitch chain, (22/40 will also work with that chain)
