Cylinder Scored

[David Barber]

I took the pipe off and looked thru exhaust wole at the cylinder. I can see several scratch stripes going up and down on the cylinder wall.

Bike is running fine and I can't afford the nikasil replating and piston job ($300) right now.

Can the bike be run with a scored piston wall? Am I risking something like a shattered piston etc or is this pretty common?

I'd like to wait about 6 weeks.

Thanks in advance for your help.

 

[gregorious77]

Your call but if its worn and the piston is worn too it is possible for the skirt to break off the piston which then falls into the crank and means full strip down and clean/rebuild
Why dont you just not ride it for 6 weeks and get it stripped down to see the damage.

 

[mideastrider]

You say the bike is running fine what prompted you to want to look at the cylinder? Some vertical marks can be present as long as that’s all they are. Not gouges or deep scratches. If you were looking at the cylinder because of performance/running issues then you should leave it parked until you can go inside and check it out. How does the piston skirt look?

 

[sr5bidder]

Well If You Want 6 Months From It Put Everything Back And Run It See What Happens

 

[julien_d]

He said 6 weeks.

Go ahead and pull the jug and look at the piston. If there's excessive wear on the piston you may not want to continue running it. It's really difficult to try and diagnose something like this sight unseen. From the brief description you gave you could have some normal aluminum deposits on the cylinder wall, or worst case you could have busted a ring or circlip and gouged the cylinder.

 

[theckeler]

I pulled my head off and found some scoring, doesn't look that bad sort of:

once I removed my jug off I found this:

Might be good to remove it to see for sure.

 

[mideastrider]

That's some pretty intense scoring. You may have a peice of the lower rod bearing cage coming a part. Top of the piston looks clean thought. Could it have had a new piston installed after the damage was done? What about a pic of the piston sides? Something has come loose from somewhere sometime.

 

[julien_d]

Just in case you didn't catch it, those pictures do not belong to the OP. Still hoping for pics of the OP's cylinder/piston. From the earlier thread that those pictures belong to, a circlip had popped out of the piston during use and caused those nifty gouges to the piston and cylinder.

 

[theckeler]

Just in case you didn't catch it, those pictures do not belong to the OP. Still hoping for pics of the OP's cylinder/piston. From the earlier thread that those pictures belong to, a circlip had popped out of the piston during use and caused those nifty gouges to the piston and cylinder.

Ya was just saying that you might want to remove the whole jug and have a look, mine didn't look that horrible till I saw the bottom end.