[Gangle04]

i set my valves yesterday only the second time in 8k and my exhaust were loose and my intake were tight im hopeing this fixes my backfire on decel problem i was having but is this a sign of my camshaft being warn out from neglect or is a little tight and a little loose normal wear and i lucked out. they werent way out of adjustment it started and ran fine even at -30c the timeing is still dead on is this normal?? i thought they were supposed to both tighten up??

 

[jjxtrider]

Popping on decal is a sign of an exhaust leak somewhere up by the head letting air in or the coasting enricher valve is clogged or the diaphragm is torn. The enricher is the cap on the left side of the carb(as viewed when sitting on the quad). you take the 2 screws out, there is a spring to watch out for, and a small rubber diaphragm. Behind that will be a plunger, see if it pushes in and pops back out. Blow it out thorough with electrical contact cleaner(I don't use carb cleaner, it's hard on rubber). Make sure the diaphragm is good with no holes or tears.

If that doesn't clear up the popping then you are running a bit lean, might need to raise the needle one groove and/or adjust mixture screw to proper setting.

 

[Gangle04]

its EFI and checked for exhaust leaks already.....id fire it up to see if it fixed it but im waiting on a thread file to fixe my threads on crankshaft to finish puting my flywheel on cant start it without flywheel

 

[Thomasj]

Popping on decal is a sign of an exhaust leak somewhere up by the head letting air in or the coasting enricher valve is clogged or the diaphragm is torn. The enricher is the cap on the left side of the carb(as viewed when sitting on the quad). you take the 2 screws out, there is a spring to watch out for, and a small rubber diaphragm. Behind that will be a plunger, see if it pushes in and pops back out. Blow it out thorough with electrical contact cleaner(I don't use carb cleaner, it's hard on rubber). Make sure the diaphragm is good with no holes or tears.

If that doesn't clear up the popping then you are running a bit lean, might need to raise the needle one groove and/or adjust mixture screw to proper setting.

The 500 carb does not have an air cut valve (or enricher as you stated).

Usually the way valves can get loose is the rocker pad, valve adjuster, or cylinder head wearing. They get tight when the valve seats are wearing. What you described is normal for 8K. Usually a little off by then and nothing to be worried about as long as its not way off. The valves and seats naturally will wear away with time (tightening the valves). The rocker pads and cylinder head wears as well (loosening the valves) so it could go either way. The big problem is when they keep getting tight. If they keep going tight its time for a valve job or new valves/seats.

 

[Gangle04]

kk thnx for the reply they wernt way off so hopefully everything is alright i picked up a thread file and am gonna get it all buttoned up today and ill get back and say how everything goes

 

[5254]

Popping on decal is a sign of an exhaust leak somewhere up by the head letting air in or the coasting enricher valve is clogged or the diaphragm is torn. The enricher is the cap on the left side of the carb(as viewed when sitting on the quad). you take the 2 screws out, there is a spring to watch out for, and a small rubber diaphragm. Behind that will be a plunger, see if it pushes in and pops back out. Blow it out thorough with electrical contact cleaner(I don't use carb cleaner, it's hard on rubber). Make sure the diaphragm is good with no holes or tears.

If that doesn't clear up the popping then you are running a bit lean, might need to raise the needle one groove and/or adjust mixture screw to proper setting.

The 500 carb does not have an air cut valve (or enricher as you stated).

Usually the way valves can get loose is the rocker pad, valve adjuster, or cylinder head wearing. They get tight when the valve seats are wearing. What you described is normal for 8K. Usually a little off by then and nothing to be worried about as long as its not way off. The valves and seats naturally will wear away with time (tightening the valves). The rocker pads and cylinder head wears as well (loosening the valves) so it could go either way. The big problem is when they keep getting tight. If they keep going tight its time for a valve job or new valves/seats.

Interesting, thank you Thomas.