EPI PATV1 Spring on Sportsman 500. Here is a pic
Known working applications for PATV1
2000 Trail Boss 325 (factionfx)
2011 Sportsman 400 (rooskey)
2012 Sportsman 500 (factionfx)
2009 Sportsman 500 x2 (highmark)
2001 Sportsman 500HO (centexguy)
This mod should work on the just about every 4-stroke Polaris machine that is NOT AN XP 550/850. Not sure about RZRs or Rangers.
As you can read through this thread, we have some people using it on the 800 EFI, 400, and of course 500 sportsman, from all different years. I just installed one on my 2000 Trail boss 325. Have not been able to ride it yet, but it appears to perform correctly.
For the 2-stroke crowd, this spring will not work. There are different options for spring-only replacement but I am not sure what they are yet. RENOBADBOY has a 300 2stroke and has been playing with the springs. Let me know and I will put up here what he says.
--------ORIGINAL POST BELOW--------
Hey guys, In the recent past i have talked up the notion just ordering an EPI PATV1 (red) primary spring for the Sportsman 500 instead of going for a full blown clutch kit.
I'm sure it's not the full effect of a clutch kit, but from emailing EPI tech support, it offers a 400 rpm increase in engagement RPM, and 200 rpm on the top.
And it is $25 on amazon.com versus 200+ for a clutch kit.
And it's easier to install. You don't even have to pull the clutch. Just the 6 bolts out of the cover. (Note that I torqued my cover bolts to 12 ft lb with a quality torque wrench....spec is slightly lower at 8-10ft-lbs but mine did not go that low).
Torque on primary clutch retaining bolt is 40 ft-lbs.
Anyway, I was going through my pictures and found some of it, and how it compares to stock, for what it's worth.
Remember that the clutches are balanced from the factory, so draw X's on it as in the pictures below so that you get it lined up correctly when re-assembling.
Stock is blue-green
EPI is RED
2012 Sportsman 500, Red.
Highlifter HD Springs all around, Moose pregressors on front (not activated). EPI 'patv1' primary clutch spring, UNI air filter w/ PJ-1 oil. K&N Model KN-303 oil filters. Bikemaster foam grips.
Last edited by factionfx; 11-07-2012 at 06:00 AM.