Piston ring gap

[Bozzy]

Not end gap…. Just wondered does this matter ie the increased gap between ring and groove. Assume no when compressed in the cylinder .
Below is the difference between expander in and out. smaller ring depth obviously recesses more .

I can definitely feel the piston a tighter fit with expander

www.flickr.com/photos/157306324@N08/53870425277/in/dateposted

www.flickr.com/gp/157306324@N08/z0F767S332

[jon]

Jul 24, 2024 19:42:37 GMT 1 Bozzy said:

Not end gap…. Just wondered does this matter ie the increased gap between ring and groove. Assume no when compressed in the cylinder .
Below is the difference between expander in and out. smaller ring depth obviously recesses more .

I can definitely feel the piston a tighter fit with expander

www.flickr.com/photos/157306324@N08/53870425277/in/dateposted

www.flickr.com/gp/157306324@N08/z0F767S332

I think you’re going to get conflicting views on this ad infinitum.

People have probably had all sorts of problems and seizures and either rightly or wrongly blamed the expander ring.

Buy banshee pistons if you can and avoid the worrying. A piston with deeper bottom ring, and no expander. Just an idea if size allows?

Jon

[arrow]

Bossy, mate. That's over two weeks since you first asked about the ring expanders. Plenty of people have given an opinion and plenty of information, both ways. You need to make your decision on this, and move on with the rest of the build.
Just my opinion.

[urbantangleweed]

Just go with your decision to fit the expanders. Likely it'll be fine, but if not, you'll learn along the way like the rest of us did over the years.

I feel that whatever you finally go with though, you'll possibly wish you did the other thing.

These are 1980's 2 strokes, the tolerances they worked to then were far wider than they are today.

[Bozzy]

Cheers I know all apologies I am thinking about it too much.

Got the replacement gaskets now so going to finish it or at this rate it will be winter