[Morg]

I've got a 91 Trail with 8500 miles. Ran fine for about 100 miles just this past weekend, then wouldn't rev past 5500. If I lift the machine, she'll wind right up to 8000. Primary was rebuilt last fall, had secondary off...looks fine. Did a compression test....90psi. (I know this is low, but wear is even) Large deposits of carbon were on the cyllinder head, but no scaring on the walls. I can't see the carbon being an issue at this point as it wouldn't just "pop up". Had to be gradual build-up This wouldn't be electrical would it??? Track is moving freely as well.
Sorry for all the writing [^]
Slight movement in the pistons...but very little.
Any ideas?
What should comp be at?? 135?
Thanks,
Morgan
Wish I had a digi-cam[!]

 

[mattgross]

i think you need to rebuild the top end, and usually i say that it would because the compression is even but yours is low, and i think you guage may be off also, some gauges seem to stick at one value, and if there is a lot of carbon you could probably jet down a size or 2 but watch the plus, 8500 wow the least you could do for the motor is a top end job

 

[Morg]

Yep, now that I've got it all apart top & bottom will be rebuilt.
[]

 

[mattgross]

good man thats the way it should be done, i bet the bottom end could use it also

 

[BIN]

#1) quit putting diesel fuel in it. that will stop the carbon.

#2) put olive oil in the reservoir (use synthetic)

#3) the formula for figuring out what your compression should be is (((M*Y)/WO^2)*(GA/20))/100*0.1T*C
where M=miles on sled
Y=age of sled in years
WO= # of times you've bought it back from an insurance company due to a write off accident
GA= Age of your gauge
T= temperature you most ride at
C= colour of your sled. use 1 for red, 2 for blue, 3 for black. (this formula only works if you sled is red, blue or black)

#4) by my calculations your sled should have been stolen in 1994 and 1997. It is difficult to predict the reliability of a sled that has not been stolen at factory persribe intervals. Regular theft insures that nobody neglects the sled when they get tired of it.

 

[Morg]

Somebody's got a sense of humour...[]

I actually do work for an Insurance company...lol
"Your in good hands"

 

[Tfin70]

Thats pretty good Bin......I had a good laugh on that one!

 

[Morg]

"C= colour of your sled. use 1 for red, 2 for blue, 3 for black. (this formula only works if you sled is red, blue or black)"

[][][]

 

[xlt]

um, did you check your belt. i had about the same problem last winter. id ride but it wouldnt go fast, chenged plugs, nothin, did a bunch of stuff. still did it. ran fine off the gorund. i changedthe belt and it ran perfect. so maby a worn belt.

 

[Morg]

Yep, I threw a new one on there to see. I've got some pics I'll be posting soon. Ordered all the parts yesterday as well for the rebuild. Going to be busy this weekend!
[]