HELP! Understanding piston design

[mainer_in_ak]

Got a few years of run time with a coupla cs 400's. They're good saws. With the long stroke and upper transfers as low as they are, the just chug through big trees with 18" bars burried. They dont run high rpms but they're a very good saw.
6 tooth spur sprocket as well.

 

[STOVE]

Got a few years of run time with a coupla cs 400's. They're good saws. With the long stroke and upper transfers as low as they are, the just chug through big trees with 18" bars burried. They dont run high rpms but they're a very good saw.
6 tooth spur sprocket as well.

I’ve been thrilled with mine. I actually dropped down to a 16” bar recently. It’s punched well above its weight.