opps....forgot i posted this question here. well i didn't find anything out on the forums i normally use so i called web cams. there is a gal, lori, boy she rally knows her stuff when it comes to cams! she got me all lined out.
i had a problem with my predator a small while back. 4th gear decided to go out. well while waiting for parts to arrive i had the head ported and the pipe ceramic coated and the piston and combustion chamber poly-ceramic coated. o-yea and the head milled .025 to up my compression. after i got my bike back from the dealer it was slower than it was stock! i was very unhappy about losing performance. i decided to go inside the engine to find out why it was running bad. i though maybe milling the head caused the cams to be out of spec. so i learned how to use a degree wheel. next i found these cam specs from web cams. i then degreed my cams. come to find out the dealer installed my cams - both of them - 16 degrees advanced!!! that would be exactly 1 tooth off!. after i put them back where they are supposed to be the bike runs like a champ! once again a very happy predator owner!
believe me they will run and idle fine when the cams are off one tooth. i couldn't believe it but it is true!
BTW milling the head .025 retarded the cams by 2 degrees. good for high rpm power.....perfect for duning in the sand!
it pulls 13 37 in second gear with padla bratt 9 paddle tires launching
i would like to try some cams with around 280 degrees duration. that ought to really wake up the mid and top end for the sand. o-yea need a 13-1 comp piston to keep the bottom end grunt. i do all my riding in the sand so i really like it to rev.
Thanks, that's better lift than I expected, that explains the quick rev characteristics of this motor. It'll be interesting to see what the aftermarket comes up with for cams. Maybe Web will whip up some .479ish 280ish combo's, scary thought ehh????
1 - 6 of 6 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
A forum community dedicated to all Polaris owners and enthusiasts. Come join the discussion about reviews, performance, troubleshooting, maintenance, modifications, classifieds, and more! Open to all Polaris models including the Outlaw, Predator, and Sportsman.