new jug back fires

[Antec1200X]

got a new jug and piston kit.bored 68mm and installed it.the bike ran for about 5 mins and quit now it back fires and sounds like a 22 rifle.i took the fly wheel off and the woodruff key is still in place it acts like its trying to fire when the piston is on its way down by the exaust port.the reeds are still in good shape.i have kens milled head on.any ideas?maybe i need more octane because the compression is higher?

 

[ant_mb]

got a new jug and piston kit.bored 68mm and installed it.the bike ran for about 5 mins and quit now it back fires and sounds like a 22 rifle.i took the fly wheel off and the woodruff key is still in place it acts like its trying to fire when the piston is on its way down by the exaust port.the reeds are still in good shape.i have kens milled head on.any ideas?maybe i need more octane because the compression is higher?

Last time mine acted like that the plug was fouled.

 

[Antec1200X]

some times it would act like it wants to run.maybe it is the plug.thats what my boss said too so maybe id better put a new one in

 

[jlsparky7]

If anything is wet, air filter, carb, bad gas then itll cause backfiring. Also exhaust leaks will cause it. Or a lean pilot or idle air screw. Check those. Do a compression check to figure out what oct gas u should run.

 

[Pwncody]

Take a lighter and burn the gas off the plug, Then take a piece of sandpaper to the prongs on the plug. see If that work's.

 

[98blaster+4]

once a plug is fouled it needs replaced!!! dont be cheap plugs are only a few bucks.

 

[Pwncody]

Im just saying If you dont have time to go get one right away then you could do what I said.

 

[Blaaster]

A few strokes with a soft graphite pencil on the tip and the earth strap of the plug after cleaning will assist in starting even the most wet cylinders.

 

[Racer51]

I'm pretty shure that your rings arent the right side up and not in line with the needle marks. It will do what you described, hard to start and when it does it pops and dosent stay running. As far as gas goes I use premium in all my 2-strokes so they start up first kick regardless. Fouled plug has nothing to do with it just has to be burned off fuel.

 

[Awk08]

did it pass a leakdown test ??? is the piston in the right direction ???,
and replace with new fuel

 

[Little-J]

cmon, dont freak the guy out.. the engine wouldnt run if the piston was in the wrong way.

the plug may be shorted.. its when the oil permeates the ceramic insulator. no burning or cleaning will fix it. get a box of 10, you can usually save a few bucks in the long run.

change the plug.. if it doesnt work, do a compression check on the cold engine n see what it says.

whats the deal with the TORS? is it disconnected or on or sort-of disconnected?

oh, and is it an 03-06 model or newer or older?

 

[Surfrjag]

Any updates antic? Btw it will run if the piston is in backwards and won't make a difference if rings are one way or another and won't fit in the bore if not lined up with keyway

 

[Antec1200X]

sorry about the delay,forgot i made this thread im too busy at work.but i did manage to get it going,the flywheel was rusty.but now it acts like it has no powerband and starves for air it has that bwhaa sound.gotta get the k,oconner jug back on it i guess