I know there was a similar topic in the past. The weight of my Heplex piston .060" is 549 grams. with pin and rings. Is it allowed to cutting off 12 mm. from the skirt

I bought another barrel I mentioned earlier, so now is the opportunity.

Thanks
John

email (option): john.kater@chello.nl

Hello John.

You can find some good info

HERE


Best regards,
Noam.

Re piston weight -

First attack the gudgeon pin weight - as previous thread, look for an internally tapered one.

Then i would remove internal material from the skirt - most 'low tech' pistons have a cast ridge/register around the inside of the skirt - this is more for production than anything to do with skirt strength/stability - you can often remove all of this and basically taper the thickness from crown to bottom of skirt.
Be careful around the 'pin bosses unless you know what are about.

As for cutting a chunk off the skirt - done this many many times - if you want to frighten yourself have a look at a modern MX four stroke piston - basically two bosses and a the ring lands .......
And no, the liner and piston do not ;lat long - they are actually hour'ed like an aircraft engine part - talking 40/50 running hours absolute max !

Back to your piston - why?
If trying to clear f/wheels then cut material from sides of piston skirt to form a 'slipper' type piston.

The length of the skirt is really to spread load/wear and keep the ring-pack @ 90deg to the bore - so if you trim some off the thrust/wear faces you MAY get more piston wobble (technical term) as the piston moves up and down - though i doubt it would make sod all difference in reality ...

There is already a tapered pin, weight 87 grams. Next time I buy a piston online I ask for the weight

John

email (option): john.kater@chello.nl