Optimizing the HT China Girl and turn in into a Lady???

[Technocyclist]

We all know that HT China Girl is not optimized. At stock, the 66cc can only deliver 3.5HP which is kind of a joke and quite ridiculous. With today's technology, a 50cc engine can deliver 8HP+++ if optimized.

So the 66cc HT China Girl has a potential to have at least 9HP if optimized, right?

Question now is that, if we do optimize this HT China Girl, how much mods can be done on the engine without sacrificing structural integrity? How much HP can be gained? or does this shorten the lifespan of the engine? Does it follow that if we put more mods on this engine, we sacrifice the lifespan exponentially?

The design of this engine is good, but the raw materials used to build it is not as good. But if the quality is as good as a Morini or a Zenoah or a Honda, then probably we can get 10HP+++ when optimized.

Just some thoughts on optimizing our China Girl and turn in into a lady...

I don't think Zenoah would produce an engine like this for whatever reasons, but if it did, i would be in line to get it.

any thoughts? any body?

[BarelyAWake]

I think yer HP estimates are a touch on the high side, I've heard the 66cc Grubee is rumored at 2.7HP... and I think that's prolly a very generous figure too... *shrug*

I suspect yer mixing "mods" when yer talkin' about integrity, the ones that seem to have the best effect are more "finishing" the engine's rough casting and careless assembly - which ofc helps the engine's longevity. Simple things like port matching, porting & polishing the intake and exhaust, cutting your own gaskets so they're not restrictive or leaky, doin' something about that POS carb (replacing/rejetting)... a general "cleaning up" and makin' sure everything is tidy. These things really are quite rough and unfinished out of the box, I like to think of the engine itself as a kit too. Oh right lol, real exhaust system, a expansion chamber - that does wonders for any 2 stroke and it's one of the most cost effective and simplest "mods" I can think of.

It's only when you start messin' with high compression mods, timing (base gasket thickness), NOS, and other "performance" mods that you may be edging towards the danger zone... but even something that would normally increase longevity like attempting to balance the engine may actually shorten lifespan - but only because you'll push it harder and higher in the redline. Generally speaking it's the low RPM, low compression engines that last the longest... but of course there's always how you use/abuse it heh

When it comes down to it these HTs are a primitive design, rough and simple, lacking even reeds. But - they're cheap and easy to work on. I really doubt that they'll ever compete with say a stock Morini no matter what's been done to them... I suppose they could if you went completely nuts on the thing and rebuilt/replaced everything down to the last bearing... but I bet you coulda bought two Morinis for the time and money that would take lol

It's all about what you get yer kicks from - if ya like tinkerin' then by all means work that HT lol, I do it myself TBH but if you want just a good, reliable, powerful motor - I'd vote Morini from all I've heard.

foureasy went... well a lil nuts lol and worked the bejeebus out of a poor HT AND ran some dyno tests for clear, unbiased results - but still got "only" about 5hp Ya might wanna check this out: http://motorbicycling.com/f13/5hp-47mph-12903.html and http://motorbicycling.com/f13/40mph-...led-11141.html