Blackice has a hard coating that they claim will improve the shift. In selecting thier cams the advise to go 8 degrees under a doo cam #. 4 degrees for the quicker shift + 4 degrees because they measure the inside radius of the ramp (doo measures the outside). I used them through the years and can tell you they DO NOT shift 4 degrees faster, a roller maybe, but not just a coating. So if you choose blackice pick one that is 4 degrees under what doo cam you'd be picking. Back when doo was putting 50's in the summits we were tossing them for BI 44, by hrps advice they should have acted like a 52, no way, they acted smaller than the 50's. A lot of cam manufactures are using the coating now so you have options. Black ice also supplies a extra washer to go under your snap ring, use it or the cam can hit your jackshaft bearing retainer. The washer would be left out if you were running the hrp primary and wider belt. The best cam I've seen is the dalton with the stainless center section. The cams that have bare alum centers are throw aways IMO, coating helps but a oem like steel center is better.
i have a dalton and am impressed by it,my friend had a black ice and after a season of riding it didnt have one mark on it,the ramp was still very smooth,same with the outer side of the helix that rubs on the bushing,it looked like it was never used,my dalton wasnt as smooth as the black ice,im wondering how the new coated skidoo helixs are ive never seen one personally,but im wondering if it has a coating like the black ice?
Last winter I used a Black Ice 44 and 46, and plan on still using them this winter. They provide a good upshift and backshift and don't get dirty or wear out like others. I'd recommend them if you don't have a roller secondary.
im not a believer in roller secondary clutchs. they seem to sift way to fast for me. if you look at most serious drag or speed racers they always run a button secondary.....u see this a lot on cats ever since they have come out with that the thunders have not been the same. when i clutch a cat i always change the secondary to buttons.rollers are good for trails.but thats it.........lol. just my opinion :hallo1:
i think im going with 286 ramps , a red spring, adjustable pins and im not shure what cam to run..... any thoughts remember im running a 2000 machz RER and yes im staying with stock secondary... :hallo6:
kawaboga, skidoo measures their cams at the inner side of the ramp, hrp measure their at the outer. The difference is about 4 degrees, so a doo 50 is close to a hrp 46 just on measurement. The hard coating may shift a little faster so you may be able to take some more off to arrive at the same upshift, then benefit from a better backshift from the reduced angle. HRP is the only coated cam maker that makes this claim. They claim 4 degrees for the coating, I think maybe 2?, but not 4 in my experience. So if you wanted to match the upshift of a doo 50, you'd pick a hrp44 and benefit by a better backshift. Same with going to a roller, the advantage is you can run a smaller cam (-4to5) for simular upshift and benifit from a better backshift. In flat out upshift riding they have no adavantage IMO except the smaller cam can hold the belt better and reduce slippage. If you wanted a coated 52/47 form anyone but hrp I'd get a 52/47. Goodwin uses a coated 52/48 with their blue spring in more than a few of their kits if that means anything. the # I have for hrp is 616 874 6338 but it is old. Let us know if they are still selling cams.
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