Piston Problem Please Help.

[gymrat86]

Hey guys,
Today I decided to pull off the exhaust and out the spark plug so I could check to see what the top surface of the piston looked like and to my surprise there is a layer of carbon buildup on the whole top of the piston. What do I need to do? Should I do a top end and install a new piston in my bike? Please let me know. Thanks alot
-Paul Graham

 

[Zenith]

Some carbon buildup is normal enough, how much carbon is on there? Is it completely covered or just a heart shape in the middle?
If it's completely covered in carbon you're jetting might be a bit on the rich side, or you're running a very dirty premix oil. If the piston isn't due to be replaced just sort this out and the carbon will burn off during the next few rides...

 

[GS]

gymrat,
You should probably stick that new piston in.....I don't think you'll be very happy till you do....now will you?
Just do it carefully. Thereafter the low compression concern should have been addressed. Break it in properly. Have fun and don't forget to let us know how much easier it starts and faster it rips afterwards.
Greg ;)