250 EXC 2 T Engine Noise

[James Herbst]

Hi Chaps. After a ride this weekend I started to hear the engine started sounding a bit rough. I have a terrible suspicion that it may be the big end bearing or the crank bearings. I have the following questions:

1. How do you test which one it is that is causing the knock. I believe that the ignition cover must be removed and then you can check on any play on the fly wheel. This will determine if crank main bearings have play. Is this correct?

2. The barrel must come off to ckeck if there is any up / down play on the conrod. This is to check the big end bearing. Any easier way of checking, that does not require the barrel coming off?

3 If the one is fine and the other faulty, is it okay to only change the problematic one ?

4. Lastly, the piston was recently done. Is it OK to re-use or must this also be replaced now?

I would appreciate any advise. I have just recently bought the bike

[Beerbelly]

Get hold of luke...

[James Herbst]

Would that be LukeMoto on the UK KTM forum by any chance?

[Luke B]

Would that be LukeMoto on the UK KTM forum by any chance?

Nope he means me.

L

[baja92]

I see you have replaced the piston quite recently, the noise will be the big end as replacing the piston 99% of the time knocks the big end out you should normally replace both on a 2 stroke competition bike.

[6daysextreme]

Ha ha ha ha ha ha ha

[mudeevee]

These comments should be saved for 1st April!

[nostinkinbadges]

That's it !!!!
All these years I've been doing it wrong.

[burls]

I've had a noisy big end in the past but my bike is fine