2002 ZX Summit 800 - Elevation issue

[Spartakus]

Hi,

I bought this sled a couple years ago off my buddy, 2002 ZX Summit 800 151''. When I first started using it last season, i wasn't able to get it to run past 6000RPM. I cleaned the carb, clutch, and tried all sorts of things and finally found out my computer was shot.

I went into the local shop to buy a new computer for it,but it was going to be a few weeks until they could get one in,so i ended up buying a used one off the mechanic, he said there were no issues with it. After i installed it,the sled ran mint, climbing up through the trail and alpine i was able to open it up to 8000 no problem. Once we got above 6500-7000 ft it started bogging down if I had it below half throttle. If i was just on the throttle a little through the trails in the trees it would just bog right down,but not so much that it would die out. When goign into a turn i would have to be atleast at half throttle to keep it from bogging down. But once we started decending back down to the truck it was running smooth.

Does this sound like another computer issue?? Anyone have any ideas of anything else i should try before i go buy a new computer?? How much should i expect to pay for a new computer?? Any help would be great

thanks

 

[Snow Duck]

carb boots

one thing to check is the carb boots and make sure they are not torn...just a simple idea....im sure someone else will chime in and have more ideas good luck....

 

[Spartakus]

Thanks, thats a good point. I cant check my sled right now because im workign o nthe road and my sled isnt with me. But i recall when i pulled my carb out to clean them, one of the boots had a rip i nthem, totally forgot about that. I'll go about replacing that before I spend the money on a computer. Thanks man

 

[Ox]

Of course there could be an issue with your carb/boots - but that may be a seperate issue....


My info is assuming that this is not a fat carb issue. When you got back in the throttle your motor was crisp eh? Not sluggish?


When the '02's first came out (snow check only maybe?) they had a stumble in them at 7000'. Doo had a new FLASH update for the 'putor by mid/late Dec '01 that took it away.

Most guys prolly never actually saw this issue if their dealer was on top of it and got most of them re-flashed before Christmas ride. However - I bought mine about 500 miles north of me, and my Christmas ride started 1000 miles west of me in Cooke City. I knew about the update thanks to Snowest.com here ahead of time. I rode straight to Rickies, but he was out and they were backed up. I rode that afternoon as it was and if you weren't carefull you could about put yourself over the bars!

Rickies wifey fixed me up the next morning and life was good!
(These are great people!)

So - not knowing what machine that box actually came off of, nor where it's been in the meantime ... I would look into the 12/01 update for the Summit8. This sounds exactly like your issue.

.

 

[Motley Doo]

when it stumbles have you ever pulled the plugs to see where she's running on jetting? Possibly a DPM issue....

 

[Devilmanak]

Yep, make sure none of the DPM nipples are cracked or broken off. (I broke one one time being a litle aggressive with removing an airbox.)
I thought it was 01 that the intake boots were so bad, but it may have been 02 also. Skidoo claimed that it was oxygenated gas that was causing them to rot/crack as I recall.
Some of them didn't last long at all.

 

[sledheadd]

The 2002 came with a valve to heat the carbs make sure its closed. Seen the same symptoms as described when the valve is open in warmer conditions like above -15.