I have a question...
Has anyone used gas???
Like the ZDZ f3A 40cc engine??
this could be piped and have a good chance in passing db testing.
The weight is that of a 26cc gas engine..... or 2lbs 11 oz.
at 930G of the ys 170 that weighs 2lbs so it is 11 oz more.
If you used a CF pipe to boot, it would not take uch more weight...

Does anyone run a zdz f3a that you know of?