Is this piston useable....

[tobytyke]

On drilling a broken stud out...the drill rubbed against the piston... ...its only a slight scuff,no sharp edges..is the piston a gonner..cheers chaps..(tried uploading pics,but aint a clue).

[coaster]

Difficult to say without pics (try photobucket) but if the damage is only slight and is bellow the rings then it'kk probably be ov with a bit of a clean up with wet & dry.

[goldeneye]

itll be ok . ive put big "X" marks on pistons, to hold oil in the bore before (my cast iron stage 4 has some of these on it, and its ran great for 1000"s of miles)

[tobytyke]

phewwwwwww..thanks lads..i did manage to upload the pics....thats cheered me up a tad..much appreciated. :fb:

[RICSPEED]

wet & dry.

according to a mate of mine ..he was told by his tutors that using grit abrasive on moving ally components is a bad idea ..and that the grit becomes embedded into the ally and is impossible to remove

any one care to disscuss ??

[shocky]

yep ive heared that as well by TERRY F (RIP) always us a clean file

[coaster]

wet & dry.

according to a mine of mine ..he was told by his tutors that using grit abrasive on moving ally components is a bad idea ..and that the grit becomes embedded into the ally and is impossible to remove

any one care to disscuss ??

He is probably right but so long as plenty of oil is used and you finish off with a fine grade I doubt there would would be any real problem. Plenty of people run open mouthed carbs that suck all manner of grit into the bore so a little caborundam shouldn't hurt. Having said that, that is quite a gouge and all I would recommend would be smoothing out any rough edges.

[warts]

Those old bike tuning books - "Speed, and how to obtain it" and "Tuning for speed" counselled the use of a file and claimed abrasive the work of the devil. I think most of that info was from the thirties. But fact is fact, however old it may be. But is it fact? I hear you say. Does it still apply on harder eutictic cast pistons?
Pistons are no longer very cheap, why take the risk? Goes for plain metal bearings too.
As far as the piston in question, looks ok, aren't there lots of holes right through 2t pistons? a mere scratch isn't likely to be noticed.