ktm 50 sx

[Cr125zrule]

hey my little bro has aktm 50 sx junior and it will not start,there is good spark,put a new plug and still nuthin there is petrol but still nuthing it dosent even back fire but will evry now and then give off smoke from the bike,,so any help would be great thanks

[HondaOnly]

Does the bike feel like the compression is exceedingly low? Those little bikes do have a tendency to go through top ends MUCH faster than a full size 2 stroke. The other thing that I would try, squirt some mixed fuel into the cylinder and see if you can get it to fire. If it does fire, than most likely you have a blockage somewhere in the fuel delivery. But that could also mean its time for a top end because it temporarily raises the compression.

[Cr125zrule]

the bike has loads of compression i tried the fuel thing and still nuthin,,checked the carb and fuel line its gettin all it needs just wont start any other ideas

[Silver_Fox]

We had the the same problem with ours, I found that even though there was spark it was not strong enough at the recommended plug gap. I always ran a tighter gap and never had a starting problem again. We had a sx senior and 2 sx juniors, they were all hard starters with the recommended gap. Hope this helps.

[Cr125zrule]

so u sayin make the gap real small

[YZER-409]

You also might be able to try a hotter plug, if they have one.

[mikew]

Is it flooded?

Kid play with their bikes.

Those KTM 50s are a ton of work. My son had one and as soon as he could start a 60 we went with the KX.

[pragmatic393]

Good advice SF!

KTM 50's are very high maint. If your not already, get real familiar with the clutch assembly.

[imanangelurnot]

I am also having trouble starting my 50 as well. I think it's the compression rate but I'm not sure where it shoud be. Any idea's??? Thanks