Backfiring issue

[timmmyc]

Hi guys,

I have an atomik 140cc YZ engine.

With a Molkt carbuerator.

My bike used to run perfectly but suddenly, it starts fine with the choke on when its pulled out. But it feels as if the bike has not as much power as before and also when you turn the throttle you can sometimes feel that its asif slipping or something.

But the problem is when you push the choke back off after say 2-4 minutes. The bike will start to backfire when throttle is given. It used to backfire anyways when it was on idle but that seems to have stopped.

Also the bikes exhaust does not seem as loud as it was before.


Any advice or suggestions ?

Thanks

 

[CHINA-RIDER]

Being a 4 stroke you shouldnt have to choke it for 2-4mins more like a few seconds.

I'd say check your valve clearences should be 0.003 inlet and 0.004 exhaust.

If you dont know how, look up the thread that shows you how to set valve clearences on horizontal motors.

Is it getting hard to start?

 

[timmmyc]

yeah, it used to start with one kick.. now i noticed theres more compression

 

[sean01]

yep, start with valve clearances and make sure your exhaust isnt leaking at the head..
just give the engine a general once over and look for anything out of the ordinary