I have now done some mods to my installation, improved the cooling of the engine. Previously I had only foam around the cylinder/head down to the mounting lugs to get high air speed around the cylinder/head. I forgot the area below (i.e. lower part of crankcase), I have now added foam here.

The change in engine temperature and fuel pump temperature was significant. I am now able to run the engine at 26-27C without needing to cool the fuel. Apparently previously the air took the easiest way out, that was unfortunately not past the cooling fins of the cylinder/head. By restricting the flow at the lower part of the crankcase by adding foam, more air passes the cooling fins.

Replaced my old YS engine mount with a new one, this also improved the throttling characteristics. And made the engine easier to tune, runs more consistent from idle to WOT.

If you are happy with “YS175CDI” power the Zero is certainly and alternative. The running cost is also attractive.

Arnstein