Looking for any tech tips. Just now starting to trouble shoot. Problem is will not stay running. The bike has backfired 3 or three times on startup and even blows the exhaust pipe out of its gimble. Once cranked up will run for about 20 seconds and then idle down and then die. Rode this past weekend for about 2 hours on trails etc but had to step up the idle to keep from dying and fouling plugs. Once the battery is dead you can only pull so much. Still letting the bike mix oil/gas. I just want the bike to be dependable and not work on it every time I take it out. I don't mind dumping money into the bike but not to take it out and will run for two hours and get towed back. Seems that the backfiring would come from maybe an air leak around the carburator or head gasket, but would that cause all the problems. Please any info would help frustrated.[img]i/expressions/face-icon-small-disgusted.gif[/img]

 

firstput in a new plug and get it to run then take brake cleaner and spray around all gasket areas if there is a leak this will find them have you had this engine apart recently

 

I had a problem a while back that my old 1990 250 trailboss would backfire at times, never had much power either. I tried everything, rebuilt carb, adjusted mixture, was beating my head against the wall until I read in a manual about overriding the reverse governor, if I remember it was just taking a black wire off of the little electronic box under all the plastic by the handlebars and taping it over. Check in your manual before you do anything like this as yours is much newer, but I had pressure washed it and apparently messed up this little box as the reverse limiter was working all the time, it would backfire at idle, start up and would never have much power either forward or reverse. I just sold it and it was still running fine, of course like the other post said I had to watch out when I backed up as it would put me over the bars if I wasn't careful. Just something to think about if nothing else works.

 

The engine has never been apart. Only cleaned the carb with cleaner and everything went back together. As far as the rest of the bike never have taken mechanically the engine apart. Before I went riding this past weekend I thought I finally had everything in good shape to ride. Put new spark plug in it and ran pretty good didn't idle the best but I figured running it would maybe help out. Well I got two hours out of it. It may be possible that the boot that connects the air duct to the carb or the boot that connects carb to intake was crimped in the hose clamp. But it seems like more than that. I have removed the carb and I am putting it back on in a little bit and try to crank back up again with a new plug and check the boots. I am curious about the brake cleaner i am going buy some now along with about 5 spark plugs. I am assuming the brake cleaner will clean around the gaskets and if a leak should see some residue of blow by right?

 

If there's a leak the engine will idle up........

 

tried and tried will not crank. pulled head and seems gasket has blown out ...there is evidence of a gasket but no gasket...

 

that would be it now that you have it off take about .020-.025 off and bump up the compresion or what does the cylinder look like

 

Cylinder looks good. Carboned up a little, damn Polaris shop did not have gasket in stock will be in on monday. I there anything I should do while in it this far? should I just use the gasket only, Coper coat needed? i will boost up compression by taking .020 - .025

 

well as far as going in farther thats your choice if you have a stock pipe your limited you could have it trail ported thats what i would do that way if you decide to get a pipe your already one step ahead as far as the gasket just use it the way it is no need for copper coat

 

Thanks for all the help. Got the new gasket ups Sat delivery. Cleaned the cylinder (de carb) got in a hurry cause couldn't stand not running any longer put all back together fired up and purring like a kitten. Cannot wait now to do some mods. The next time i tear it down.