65cc 2Stroke won't start - Please Help

[James93]

Hi there, I am new to this forum and am just hopeing that someone could give me some advise with a few problems I am currently having with a 2009 Cobra CX 65 (Similar to KTM SX65)

I bought the cobra as a non runner from a friend relatively cheap, hoping that I could quickly get it up and running and make a little profit. When I purchased the bike it would kick over after some time but then run terrible while smoking quite abit, then foul the plug, bog and ultimately cutout. I then would clean the plug, tweak the carb and try again but with no progress.

Next I went out and purchased a piston kit with a little end bearing and installed them, cleaned the carb, filter and plug. But since then it won't kick. I can tell it wants to fire up but just won't. If I try to bump start it, it gets closer to starting but doesn't start properly, bogs and dies. The plug is producing a spark and fuel is flowing in to the carb. So now with my limited mechanical skill I'm currently stuck as to what to do next and as I don't intend to keep the bike I want to be spending as little as possible to get the bike up and running again.

Could you guys please suggest what to check next? and if you have any ideas what the problem could be? Any help would be greatly appreciated.

Also the air filter is well used and the plug has been fouled and cleaned many times (I'm not even sure if the plug is the right one for the CX65 it definitely fits but may not be hot enough) Could it be as simple as just these causing my problems? I just don't want to spend anymore than I have to. Having already had to buy the piston kit, sprocket, transmission oil. I may just be lucky to break even.

Many thanks in advance, James

[mudcow007]

did you check compression before you spunked out on a piston "kit" ?

new plug and air filter would have been a cheaper first option...just saying

[James93]

Hi mudcow, the piston change was way overdue, as I know 100% it was not changed by the 2 previous owners, the second of which ragged the bike around and was well over the intended size and wieght the bike was designed for. Thanks for the reply

[Pjay]

2 stroke engines are relatively simple beasts.
First check it sparks well, and that it has compression, if these are fine, overhaul the carb.

If this don't fix it, it's broken.

[Suntan Sid]

The correct plug for your bike is an NGK BPR7ES, buy a new one, gap it correctly, replace the air filter then try starting it, you could try starting it with the petrol cap loosened or off, to make sure the tank breather aint blocked!
Does it have a choke, if so is it working correctly?
____________________
"Everybody needs money, that's why they call it money!"

[Vincent]

What's the correct mileage?
____________________
Space Is Deep