Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

That's an awesome find Gamma !

I'm planning to return this engine to them, so prefer not to thinker with it. Although it's good to see there is a way.

I was thinking to make shorter push rods, that way the vavle will be properly closed. And extend the exhaust one to allow better scavenging to achieve true Harley low RPM character. I did that on my R90S and it idles low and beautifully after it's warmed up.

I must say this engine has lots of potential but needs a bit more comprehensive design. Specially with the V35 angle there will be lots of shaking and vavle adjustment ability ( probably in easier way) is needed. The crankshaft also seems a bit thin. Whilst by design there is no load on the engine, overtime I wonder if it will lose its shape and strength, especially as the large camshaft gear and the ignition timing gear feed of it.

Sad to return it because my friend would have loved it but don't want to disappoint him with constant tinkering needed.

I am waiting to get H75 engine. Apparently it comes with the upgraded cylinder to prevent coolant leak.  Fingers crossed it will have minimal issues !