What happened to my motor?

[snakedoctor99]

Ok so about 7 months ago I rebuilt my motor after i blew it up. I bored it from .20 to .40 with a new wiseco piston. I was out riding one day and I lost one of my exhaust studs and when I did my motor lost all power and I had to let it cool before I could start it to ride it home. I ordered new studs. I put in the new studs went riding for around an hour and a half and it done it again and lost all power and compression. I got it home tore into and I blew it up again. The whole Exhaust side of the piston was badly scarred and the rings were seated. There was also a chip of the side of the top of the piston What would make this happen? Only reason I'm wondering is because I rebuilt my motor again and dont want to blow it.

 

[245stroker]

Sounds like a lean condition. A broken exhaust stud shouldn't cause that tho. Once its rebuilt, do a plug check. Do you have an aftermarket exhaust on it? What are you running for jets, needle position?

 

[snakedoctor99]

Im running stock jets and exhaust and Im not for sure on the needle position but I imagine it's stock too.

 

[yb200]

with oil injection block off and a k&n i would bump up the main to a 250.....stock is 230.....put a 250 in and a new plug ride it for 15-20 min and check the plug....should be a cardboard color or darker...

 

[snakedoctor99]

Ok Im getting a jet kit from vitos in the near future. Do you think that it would be safe to break in my engine on stock jets?

 

[yb200]

i would waut till you get the jets and dont buy a jet kit just buy a few get 240 250 260...and a few plugs

 

[foolish913]

jetsrus.com has all the jets you need if you dont want to buy a kit

 

[snakedoctor99]

My instructor is supposed to be bringing me a 250 main tomorrow. Im was going to try that and see how it worked out before I ordered a kit.