Scooterotica

how long to run in new rings & piston,not had a re bore it lost pin in piston and broke rings,std 66mm bore

You don't say what type of cylinder it is. If it's nicasil lined, then about 250 to 500 miles. If it's cast or steel lined, then around 1000 miles.

did you check piston,bore clearance? if above 3.5 thou,then a few hundred miles should do.

IMO.....if your barrel hasn't altered and it's just new rings/piston then 50 mile should be ok....but that's my opinion..

mick1 wrote:IMO.....if your barrel hasn't altered and it's just new rings/piston then 50 mile should be ok....but that's my opinion..

That's a good opinion too as my new piston went in and then used as normal,no worries.

1000 miles?
There's some barrels would be half worn out by the time they've been run in!

has it been rebored to suit?

If not then I'd go with 50/100 miles as long as you've "glaze busted" the bore

Chris

thanks everybody for the reply`s,its a cast barrel,no need to re-bore only a very very small chip on exhaust port but that`s sorted,1700 miles,3thou clearance on piston and ring gap 10thou