Motor lean? (pics)

I just pulled my engine apart to replace the piston and put a new S1 Hotcam in. I think it looks like it was running a tad lean. Are my valves all right or should they be replaced? The hours are unknown on the bike. I plan on putting it together tonight and running it this weekend. It might be time to get a 07 head. Thanks




The first picture the piston looks to be slightly detereated. The secon picture either the valves are detereated or have deposites on them. The cross hatching looks good, there is a line of film/carbon on top. What do you remove that with? also should i use a ball hone or some scotchbrite? Thanks again.

I always wipe down there barrel with ATF, it has great detergents in it. Then after that wipe it down with parts wash. Remember to use paper towels and not red rags when doing motor work. Also assemble it dry!

Looks good to me...

That's what my cylinder looked like and the bike shop told me NOT to hone it. Said if it already has good doesn't need done. I don't know...just sayin'.

That's what my cylinder looked like and the bike shop told me NOT to hone it. Said if it already has good doesn't need done. I don't know...just sayin'.

Don't go there anymore:busted: You have to hone it. Sure the cross hatch looks good and it always will because the cylinders are so hard. You hone it to get the cross hatch cleaned out to restore it's capability to file and match the rings to the cylinder for a tight seal.

too lean!!!!

what about the spark plug???white...?


Guys you don not want any black fluff stuff any where, being a tad is OK. The Creamed coffee look is very nice, the cleaner the better. some pump gas will leave alot of crusty stuff. but NO Carbon is good. the piston has a tad of grey that is very nice in my book.

If you start to burn oil you get dark crud all over, the valves get dark from the glazed oil. you see alot of that on picture here at TT and most say it is normal as it is because most times the motors have alot of time on them.

I rather see them like you have

Have a shop de glaze the cylinder or get a scuff pad with hot soapy water and have at it. clean it up to get the rings to mate up on it.

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