Piston Condition

[Moarpower]

Hi guys, based on this image, would you clean up the piston, measure and replace rings and hone the cylinder or would you replace it?

1980 gs850g

 

[Moarpower]

Another

 

[Moarpower]

Cylinder

 

[rphillips]

For me when that deep inside of an eng. If you see anything where you need to ask should I replace it, YES replace it. if within reason. Wouldn't spend $500 on a piston, but anything reasonable yes replace. Just my opinion.

 

[Rich82GS750TZ]

It’s always a good idea to state the year and model. This is why we use signatures. You won’t forget to tell, And we won’t have to ask.

It would be good for you to explain why the head and barrels are off. Is this just a basic top end refresh, or did something catastrophic precipitate this endeavor?

I don’t have a lot of experience doing this (2x), but based just on your pics, I’d say scrub the carbon off the pistons, hone the cylinders, new rings would be appropriate. Consider new valve seals since the head is already off. And if you’re gonna do that, may a well lap the valves.

And replace what? The whole engine?

 

[rphillips]

Ohhh, just assumed he meant that scratched up piston, but he didn't say piston.

 

[Moarpower]

Sorry guys , I did voice to text on that post while in the gym.
Asking about pistons. Fixed the first post
It's a 1980 gs850g. I removed it to inspect for damage after the tensioner failed.

 

[zed1015]

The scuffing isn't critical, It's the piston to bore clearance that is.
As long as it will tolerate a hone for the new rings without exceeding the specs just re-use them.