Is this piston reusable?

Rebuilding my 750-four engine. Took the pistons out today. Both the pistons and bores (which are stock size-probably originals) are in spec with the factory numbers, and the bores and pistons look just fine....except for piston #4. Here is a lousy pic of that piston showing some of the skuffing near the piston pin boss.....



This piston is scuffed on three sides 90 degrees apart (but not on the forth side). Oddly, the bore shows nothing in these areas (which measure out fine). The skuffing on the piston looks bad, but won't catch a fingernail. I'm poor, and so I'm wondering if I can reuse this piston? Or should I look for a reusable used one (anyone got one)?
Thanks!

I hate to say that piston looks pretty bad. That piston looks more than scuffed. If any of the others look anywhere as close I would replace all of them. The question is; What do the cylinders look like. If you can remove any apparent scuffing with 4-5 swipes of a hone than I say they are OK if it takes much more than that, you will require to have them bored.

got to agree with otakar, with that many socres on th piston I dont se any way that the cyl is 1, not going to be scratched, and 2 that it is going to be round.

new set of oversize pistons and rings, and bore cyls out, build it right the first time.

I noticed Z1E has 199$ cb750 complete oversize piston kits, would he be able to use them?

www.z1enterprises.com/SearchResult.aspx?All=True&KeyWords=impk

I'll try to get a better pic. The piston is not as bad as the pic shows (there are reflections in the piston that look like further scuffing).

Surprisingly, as I said, there are no markings in the bore! And the clearance (which should be .040~.067mm) is correct at about .050 all around the piston. Also, the scuffing cannot be felt with a finger. I can't afford new pistons (let alone a single one), so I was wondering about reusing it.

What ever you do, do not use any kind of abrasive pad to clean the side walls.

Does anyone know if this will build up a piston skirt and fill in any imperfections:

www.swaintech.com/store.asp?pid=10971

One of the guys on another forum mentioned this place some years ago. Maybe it would be worthwhile to contact them and send a pic of that piston to see what they can do. For instance, it is only 15 to 20 bucks for the skirt coating.

These are pistons I did for my bike.

Here is an individual piston.

cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll...e=STRK%3AMESELX%3AIT


This is my auction, those pistons are in great shape. I also have the cylinder sleeves they were used in (however the sleeves have been removed from the block).

I would be saving these pistons for spares if I did not need the space.

If the piston is round i would use it. I use 220 sandpaper to remove any aluminum and then sand crossways for some oil retention, steel whool will final polish and remove any remaining aluminum deposits. I've never had a problem with this and you have good bores, which is the key to a tight bore when it's re-installed. That engine isn't going to know any difference.

hardr0ck68 wrote:

cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll...e=STRK%3AMESELX%3AIT


This is my auction, those pistons are in great shape. I also have the cylinder sleeves they were used in (however the sleeves have been removed from the block).

I would be saving these pistons for spares if I did not need the space.

The only problem is that yours are for a 650 and his are a 750.