Carbon on Piston

[goldman15]

I'am doing a top end job right now just waiting for my cylinder to get back from the shop. The piston has a good bit of carbon build up on the top of it. Should I clean this off before putting it all back together? And what does the carbon build up indicate? Thanks

 

[BRush]

Check this out:

http://www.off-road.com/dirtbike/mar2001/mar01rsDecarbon.html

 

[slcyclerace]

The carbon indicates that the bike has been started and run and why dont you throw in a new top end since it's apart. It's less than 100 bucks and everything wil be fresh. (Cylinder at the shop for a power valve cleaning?)

 

[canyncarvr]

Unless you are following some book advice that says to replace the rings every 10 hours, the piston every 25...and you're on the 10 hour mark and following the book (whew!!), why are you worried about it?

If you ever take your bike apart to find NO carbon on the piston, let me know what oil you're using. If it's a 4-stroke, let me know what GAS you're using ;)

Re: the offroad link...

Scraping a piston with a razor blade (with a caution against hot spots)? Cleaning an exhaust port with an exacto knife!! Holy kaw!! PLEASE use a hardwood spatula. Maybe some Gunk.

Using an old ring piece to clean the ring land works pretty good (pull, don't push). You can get a ring land cleaner from most any parts store. Chances of metal removal from the land are pretty good. That's an error!

try not to mar the surface any more than you have to;

You don't HAVE to mar it at ALL!

But then, they are going to reuse their RING(s) for crine' out loud. Maybe that has something to do with the maico part......

Buy a new piston/rings! Check your cylinder/piston tolerance markings (a,b,c,d) and get the corresponding piston from pro-x......if you cylinder isn't goobered.