I can see people asking for help but some of the people on this site make there living selling these kits & spend many hours testing to get the best for the consumer Kits like DP & OutDoor Shop & when all is said & done your way ahead buying one of these kits for best performance & least amount of money.. . I know I test myself but I have my own track dyno & engine dyno from my race days I have 200 + miles on my F7 from being on the dyno & testing on the lake before starting to trail ride To try to get that little extra edge by only clutching costs these shops lots of money & time
BYofficer I agree but I have clutched every sled I have owned with polaris or cat weights with cat helixs and springs from hpe and cat and have been happy ,a homemade kit like this only cost 75-100 bucks and I already got most of the parts. Why load the shit out of these things with weight?Why not controll the revs with the helix?outdoor shop why not load the engine and let it overrev on the very top better top end ,better top speeds after the 660 foot drag is over. Im not sure that 57/50 is the way to go just have one on hand by the way that is a stock zrt 800(147hp)and stock t-cat (165hp) helix.IF your worried about over rev run more side pressure on the secondary sheeves like hpe red spring for no slipping on a steeper angle and run it loose 2nd mabey first position on secondary .
I was thinking of a similar plan..........I have a 57-50 sitting in the garage but I think it will over rev on top too. I have a 56-52 that I just bought and it doesnt work either.........good hole shot but dies at 500 ft......and slightly over revs on top on hard pack...........8000rpm
I'm running 62/50, with green AC spring in secondary wrapped in #2 hole. Shifts around 7800 and runs to 7900. I believe this is improvement over stock with no top end loss. I only have 90 miles on so I will start playing with primary when I get some miles and seat time on it. I've played with a few helix's and this is the best so far....at least for not touching anything but the secondary.
Most of the time you should not control engine RPM with the secondary. Go to Olav Aaens clutch handbook or ask any top tuner and they will tell you that. When these kits include Helix's and or secondary springs they are most likely trying to change the way the sled shifts or backshifts. If you over-rev with a steeper angle helix may mean your not shifting out far enough and a stiffer secondary spring will only make it worse.(Unless belt slippage in the secondary is causing the over rev)
I think the stock clutching is pretty good, it hardly overrevs as it is maybe 200 rpms Im going to try the 57/50 or maybe even steeper, it should accelerate faster and if the finish angle isnt too steep it should loose no top end ,I will try the the hpe red secondary spring for more side pressure and see what happens.
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