Just going off what i've read. The "Ring of Death" as Eddie calls it is,

Eddie Sisneros, on 09 March 2010 - 04:44 PM, said:

Check this thread for the photo i used as well as the photo of head and eddie's posts:
http://www.thumperta...nocking__st__20



Since my con bearing feeling solid, and my cam chain is now sitting correctly on the guides. I'll be reinstalling my cylinder, head, and cams to see if they seat any better this time. Going to wait til I have an extra set of hands to ensure smoother installation.

Edited by steezin_and_wheezin, 31 May 2012 - 04:56 AM.

Big difference between piston touching the head and piston almost touching the head.  The picture you reference shows no contact.  If the burn pattern is indicative of  a loose rod bearing, I stand corrected. Certainly the thing to do is to check the rod bearing if there is an indication of a problem.

Edited by Noble, 31 May 2012 - 09:41 AM.

Sorry didn't mean it to sound like i was trying to win an argument.. I've still learned from your posts

Hoping to find some free time to wrench again soon, swamped right now..

No argument.  I learn as well.  I like to clarify things that don't quite sound right the first time.  I'm not enough of an expert to try and read piston tops.  I know an experienced person can learn a lot from burn pattern of 2 strokes and 4 strokes and I'll leave that to someone else. I can however see (and have seen) mechanical contact of valves to piston and pistons to head and in this case there is none.  Interesting that the burn pattern indicates a problem and to check further.  Guess I never read the thread on ring of death before.

I was only pointing out the light coloured ring in the centre of the piston crown, as this can sometimes signify a bad rod bearing. Thought it was best to bring it up, in case there was an issue, before the owner finished building the engine.

Turns out nothing is amiss and everyone is a winner.

Keep up the good work.

Ah so you Were talking about the center! For the ring of death I thought you were talking about the intake side of my piston having less carbon build up. As Noble mentioned the mark in center of piston is casting mark, but you bring up a great point. I'm not sure why it is cleaner than its surroundings.

With the con rod bearing checking out, and my cam chain realigned hoping to get another quick test fit ASAP

'Preciate all the help guys!

Just to add, after checking out your link, i believe i may have got this arse about face also. Sorry for confusion, just trying to look out for you.

Ha.

Last piece of advice, make sure you enjoy the bike.

2nd test fit went well! cams seated and chain was right on. I had the chain off the back guide and the front guide was installed incorrectly. I was torquing the head down, got the 4 inside the head, and 2 on the side. was snugging the 2 small nuts down that secure the cylinder to the studs on block. first tightened nicely then the second one just sheared off right in my hands!



Was sitting there miffed that i was going to have to undo all that i did and get the stud out, wait weeks for new stud to ship and then reinstall everything. My roommates family was in town, his older brother and i were talking and looking over the drz. right there he made an offer for the bike i couldn't refuse. I'm out of room, and brought home another cheap goped project this weekend. even after finishing the drz i don't think i would have come out as well as i did. Plus i am helping a good friend, I'm sure i'll get to jump on it next time i'm down in NC.

I've learn tons and got a little hands on time. Hopefully the knowledge i've gained will help me want to split the SuMo open and wrench around.

Thanks everyone for all the help, i'll be sure to update after he gets some time on it.

A last photo:

I don't suppose I need to point out how much the treads are stretched from over torque.  Could of been bad before you laid hands on it but also a good reason to look things over carefully.

There is a possible way to get the stud out without taking the cylinder off but I guess that is somebody else's problem now.

Most definitely, also the nuts both showed sings of shotty wrenching. I was using the open end of my box wrench,  tightening 1 handed. Guess i still should have watched closer.

Yeah there's plenty of stud left it there. Had a couple ideas, but don't think i could have gotten the stud out without pulling the cylinder off. With the jug off and a pair of vice grips it won't be a prolem to get it out though.

I still kind of feel like I gave up on the project, but all in all- I don't have to hassle with selling on craigslist, worry about the possible bad valve guide, I made profit, learned lot, and am helping another friend. So I feel OK letting this one go as is.