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Help!!!!

1.6K views 4 replies 4 participants last post by  Russ C  
#1 ·
I have a 2001 polaris magnum 500 All stock no mods 2600miles on it

It was running fine, than I parked it in the garage and it sat for 2 weeks
Than brought it out to ride, it has a miss in it when you back off the throttle & accell. happens around 1/2 throttle doin 15-20mph when throttle is wide open it does 40mph with 2 guys on it & blade on the front. Doesnt miss abeat wide open.
just around 1/2 it misses when you back off the throttle or accell.

it recently has had a new camshaft in it ( WORN exhaust lobe common problem)
Spark plug & wire new, new fuel filter
My muffler is rusted out on it.
have replace needle & seat. new o rings in carb on main jet
ive set the main jet is about 2.5 turns out.

seems to miss more when its warmed up than cold.

any ideas?

it has been a great quad up till this.
 
#2 ·
my buddy had the same exact problem with his sportsman 500..he also put a new cam in his everything was right on it and it had a miss and backfired..he tore it back apart and put it back together its ran fine ever since..we cant figure out what we did right the second time! Did u make sure timing isnt advanced or backed off just a tooth or so?