My piston on my malossi 210 has melted in the middle, it´s not yet a hole in it, but not far from. Could this be because i have not ported the intake hole just the ports to the cylinder?
I use a 26 mm carb and it has worked fine until now.[:’(]

Best regards
Patrik Grann

Check the timing too. It could be too far advanced causing the „pinking“ that Dylan mentioned…but I too would say that your main jet is too small.

The thing is, there has been no pinking and I use the 135 mainjet.
If i use a bigger mainjet the engine just bludders. The timing is ok to,I checked it just a couple of weeks ago.
Looks like I will have to split and check the hole engine again!


Patrik Grann

PS Do not miss Gothenburg run and race weekend http://www.scooterklubbgoteborg.com/runrace/start.html DS[:bounce:] [:drink:] [:dance1:]

I presume you mean that it has melted at the top. This is probably due to an incorrectly adjusted carb or too small a main jet. Check you spark plug colour.