Piston Ring Direction

[0Gravity]

Hi All,
I posted this in the premium troubleshooting section also...Sorry for the double post but I need an answer to this question As quick as I can get it!

I am a total Newb to 2 stroke engines, and this is probably one of those newbie questions, but here goes....
I am rebuilding the top end of a 720 engine, and bought a Wiseco piston kit, and am in the process of assembly when I came to the point of assembling the rings onto the pistons, I notice that the top ring has a flat side and an L shaped side..Neither the piston kit directions nor the Shop manual I downloaded from here mention which direction this ring gets installed on the piston...eg. Flat side up or down?

If someone could enlighten me that would be great!
Thanks in advance,
Mike

 

[cbjrumble]

I cant remember when i built my top end, but my advice is look at your old pistons if you still have them.

 

[derek]

the L-shaped ring is the top ring. the L-shaped side goes up. there is a little pin in each ring groove. the ring end gaps go at the pin. this stops them from turning on the piston. the side of the pistons with the pins goes towards the carbs. THIS IS IMPORTANT!! if you put pistons in backwards, the ring end gap will cross the exhaust port. it will catch on the edge of the port and break the top off of the piston.

 

[seadoosnipe]

Debated before.....

This was debated before and there were a lot of varying opinions. A premium member, Squiddo, was the one who came up with the correct answer. I was way off base with my answer.

The rings you refer to are known as "dyke" rings......

The post was pretty long, but I took the advantage of grabbing his link to post for you here, in this thread.

Follow the link and you'll be able to read and see the correct installation of this type ring............ http://www.motorera.com/dictionary/DY.HTM