Hello,
I'm new to the forum, hoping I'm posting in the right location.
Need to rebore and replace piston in a C15 sportsman 1966
The piston does not have any info on the top of the dome but under is marked 16114, I would imagine this is std but I would like to confirm.
Next question is what would you suggest to fit as an oversize piston. She's only a weekend soft use bike so I will not be racing her up and down the street. Be good to get some advise.
Thanks for your time
The rebore size is dictated by how much wear there is in the bore.
Firstly , take one piston ring off carefully and place in the bore.
Use the piston to push ring down the bore and measure the ring end gap.
Push down a bit more measure gap and again push down and measure.
If the gaps are not widely out of spec , you may get away with a set of new rings and a quick whizz round the bore to declare it.
Usually , if there's no +020 or anything on the crown , then you're standard.
Try this 1st