250-500cc Don't mix rings and pistons

I have just had a bad experience fitting new rings to my WR360 and ended up stuffing the piston, rings and barrel coating.
It appears that Husky rings are not the same as Wossner rings. So be very careful what you use together. The size/height of the ring pin in the piston and the matching notch in the rings is different, meaning in my case there was effectively no ring end gap.
I trust that others may learn from my mistake before they fall in the same trap.

The sad and all to credible story follows.
I had to remove and fix the pipe recently, so while the pipe was off I looked up the exhaust port to check the piston and bore. I noticed that the while the piston and bore was in good shape the rings showed noticeable wear. So I got some new husky rings, a new fmf pipe and boyeson reeds to give it a birthday.
I pulled it apart giving the carby a strip and clean while it was off.
I test fit the rings in the barrel to check end gap before fitting them to the cleaned up piston.
The rings fit on the piston like normal and the barrel was fitted over with the usual juggling act.
Bolt it all back together with new gaskets/O rings and then turn it over with the kick start.
It had a little extra resistance but after a few revolutions seemed OK.
Finish by putting it all back together ready for a test run in the morning.

Starting is a bit difficult with the new parts and assembly oil etc not letting it run properly so I have to hold a few revs on until i can adjust the carb. not unexpected.
restart it and try to warm it up but then it just suddenly dies.
go to kick it back into life a she is solid. WTF.
Push it back in the garage and leave it for a minute or two and it turns over again but doesn't feel right.
pull it all back down again and find the rings have expanded and caught in the side transfer ports plus been forced out at the piston pin location to stuff the lot. Not happy.

So the moral of the story is know the piston brand before you buy and fit new rings or just go the extra cost and fit a complete piston kit as it could end up being better and cheaper in the long run.

Yep, a pretty basic rule only use matching brand pistons and rings, sorry you had to learn the hard expensive way.

Man that sucks i just buy the oem rings yet to do piston
I may go wossner route after 40 or so more hours.
So you didnt check ring end gap?
I read this about a 250 wossner piston kit too the threads
In the cafe husky i think.

the story continues...
so I got a new Wossner piston kit and the barrel recoated to suit.
While re-assembling i have checked the ring end gap in the barrel which is OK, as it was last time, but the rings on the piston have not fitted properly around the ring pin again. there was a bit of a bur from the ring pin being pushed so the rings were binding coming up to pin and the notch in the ring was catching the top of pin as well, so it wasn't allowing the ring to close over the pin. i cleaned up both areas to allow proper fit.
I will get to test run it tomorrow to confirm all is OK now, but it could of been a repeat disaster if I hadn't done the extra careful check.
So again, be careful when fitting rings.

FYI This latest Wossner kit was a complete set with piston, rings, circlips as normal.
I am thinking it may be a 360 thing as I have never had this problem with any of our other bikes.

With the fixed piston and rings fitted it started and ran fine.
But to be sure I gave 3 heat cycles at home before taking it for a trail ride and finishing running it in.