I have a 2002 500 I that I am planning on taking to Colorado in the next few days. Would like to check out some trails at the 8000 to 11000 ft. range. 100 miles tops. Do I need to re-jet for this trip?? Performance is not the issue but just don't want to hurt the engine. Can I do anything less complicated? Different spark plug. Different fuel?

 

I've had the Arctic Cat 500 TRV's and the Polaris 500 up to 9000 feet and they ran well. Not strong but well. Without changing the jets. Two years ago we had a Polaris 90 2-cycle with - and it strugled at that altitude. The 250 Recon ran moderately well at 9K also. 11K is pretty high for standard jets IMO. Up to about 7000 feet it was difficult to measure any noticable change in power.

I always use non-corn fuel at the highest octane when going in the mountains. Not sure what impact that makes but I figured it can't hurt.

 

tdauber,
I just got back from Colo. We rode the Lake City , Silverton & Ouray areas. The 2 650 Cats in our group had to be rejetted for the higher elevations. As did the 2 650 Prairies & the 750 Brute Force, which were all done before we left. We were up to the 13,000 ' level at the highest point & 11,000' to 12,800' on several occasions. Cinamon Pass & Engineer Pass to name a couple. I didn't rejet mine the first day & neither did the other Cat 650 rider & they ran poorly at the higher elevations. Our Cats have # 122 jets in both carbs. The Polaris dealer in Lake City recommended a 10 to 15 percent reduction in main jets & rejetted mine with # 110 jets. The other Cat rider rejetted his to # 115 jets as he rides in the 8,000 to 10,000 level where he lives in NM, & he won't have to change back to the stock jetting. But i had to as i live in Ok. & much lower elevations. Both Cats ran fine after the rejetting. Hope this helps a little.
Regards, Jerico1

 

I like the Silverton Ouray area. I have been there once but it was early in the spring. I hope to go back and do some riding within the nex couple of years. Figure I could make a long trip and stop at Moab and St Anthony on the way down.

 

I went to my dealer (125miles one way). Had a carb problem and told my dealer that in a week I would be riding at 4500 to 10K+ in colorado. He fixed the carb (bent needle and a "buggered" jet) and said no problems riding at those heights. I didn't get the number of the replacement jets but cost me $53 (labor $48 hour and $5 parts/tax), not bad for jumping right to mine since he knew I lived a bit away from the shop and going a extra hour out of my way instead of going to Reno (55 mile from my house).
The cat ran great at 10200ft and didn't have to change the plugs unlike my father's quadking 250. His ran for about 12 miles before really fouling out.

 

Hey, thanks for all the replys. My dealer is closed on Mondays so could not call to get their input. Thanks to those on this forum, I can journey to Colorado with confidence. Thanks.[img]i/expressions/face-icon-small-smile.gif[/img]

 

There is a really nice dealer in Norwood Co. that isn't real far from Silverton & Ouray if needed. Was there once and the people really left a good impression.

 

I had my AC650 rejetted from the stock "22" down to "14" at the recommendation of my dealer. Out in Moab and up to 11,500 on the Paiute Trail, it never gasped or acted like it was struggling. Even with my wife on board riding double. Still was able to hit 55mph on a stretch of trail so it still went as fast (or faster) than I needed.

Need to get it back in for rejet for Missouri.

 

I heard jetting is a must above 8000 to 9000 feet. Can't wait for everything to be Fuel Injected!