Hi All.

I have owned this bike since new. It's been well taken care of and I know the full history. Annual oil/plug/filter changes before the first ride of the year, using either M1 or Amsoil. Front diff, trans, wheel hub fluid changed either every other year, or before a big riding trip. 360 hours, 3700 miles on the bike. And while I'd never describe it as a power house (32 hp new), it always had enough power to do everything I've asked of it.

Until my last trip to Hatfield McCoy, where I have made somewhere around a dozen trips to over the past 20 years. While the quad started, idled and generally ran fine... I found myself at WOT when trail riding way more than ever, just trying to keep up with friends. It's like the quad has lost power at the mid & upper end of High gear. No sputtering, no backfiring, no rough running, etc. Idle and lower speeds seem normal... just losing it on the upper end, esp steep mountain switchback hill climbs.

I was able to complete the trip and ride everything my buddies did. But instead of occasional blips of the throttle to WOT here and there, as usual, there was at least a dozen or more times I was WOT for 2/5/10/15 seconds just trying to keep up. And that is very abnormal for me, on this quad, riding the same trails I have been for years.

My original thought was maybe the rings are worn. So I was going to do a compression test to begin with, only to search and find out you can't compression test these engines due to the pull cord compression reduction feature of the camshaft. Thoughts?

The carb is also original, never rebuilt. Annually seafoam the snot out it before winter. And while I've never had problems with it historically, wondering if it may be the cause.

Lastly, friends thought it might be a clutching issue. I did have the secondary (driven?) clutch replaced at 2k miles. I don't hear, smell or see any obvious signs of clutch issues. Although I haven't ripped open the case either.


Any thoughts? I'm hoping this era of SP500 is known to lose power like I'm describing and you guys know why w/o seeing it. Missing Old Polaris Tech - RIP.

 

Since posting yesterday, I was thinking about our last ride in WV, and another symptom now that I reflect back is the EBS when going down hill was not nearly as strong as usual. Meaning I was freewheeling more downhill than I was used to; EBS was not doing as much of it's normal thing.

Wondering if this points more towards the clutches.... vs engine. Is EPI in my future?

 

Bumping for any input. Thx.