[joesno500]

i rebuilt my sled not to long ago, and i didnt have much time to mess around with the engine. it worked for awile perfectly, then i went on a trail 4 like 20 miles, and it started running rough when it was hot. we just got like a foot of snow, and the sled satarted sounding funny, i checked the plugs, redid the carbs, and almost everything else. i think there is a somewhat new muffler on there because on the right side of the sled, it looks like all of it was replaced, and i was wondering if the muffler might have something to do with it or there is something else.
thanks

 

[CORY9]

Just to clarify here the sled is running rough and sounding funny? Is it down on power?
Have you performed a compression check just to make sure?

 

[tifa_5_2000]

piece of something in the exhaust?

 

[joesno500]

it sounds louder than normal, and jthen when its warmed up then it makes a high pitch noise like scratching and it comes from the primary when its more than 4000 rpm and it doesnt feel like any decrease in power

 

[polaris_dude]

hey thats kinda funny, i got a 1997 indy 500 thats doin the exact same thing, and cant figure out wuts roung with it, nobody seems to no, i got alot of different answers

 

[63November]

There might be several problems. If the muffler is newish, I'd check to make sure it's the right one for the engine. Sounds out of the primary could mean wear in there either in the weights and pins or in sliding bushings. Pull the clutch and remove the outer plate to take tension off the spring. That's a simple way to do a cursory inspection. You should be able to see if there is wear in the critical places. Running rough is probably a fuel problem the way it sounds. Are the enrichment valves closing all the way? Inlet valves in the carbs good/ tight and no junk getting in? No excess fuel puddling in the impulse side of the engine? These are just a few questions I'd look for answers to.