JD380

My Feedback: (133)

Motor in question: OS SF 46, ringed 2-stroke. Shouldn't there be a pin in the piston's ring groove to keep the ring's gap from hanging up in a port?
I know outboard motors have them for this purpose, but I could be comparing apples to oranges.
I'm new to rc motors, so let the education begin! Thanks in advance for any info.

w8ye

My Feedback: (16)

The K&B doesn't have a pinned ring. But It does have port dividers.

Enjoy,

Jim

ChuckN

Some engines have them and some don't. It all depends on how wide the ports are in relation to the cylinder bore. The ringed OS engines have a "bridge" across their exhaust ports and don't have any real problems with snagging ring ends. Their transfer ports are fairly narrow as well.

modelmaker3

My OS .46 SF engines do have pinned rings.
Dave