this engine kit has every design trick in the book to make it low power so it can pass gov't regulations;
The only 2-stroke engine legally imported that passes 2012 EPA is the real Grubee Skyhawk.
The new 2015 engines are just hitting the US in a the next month or so, only registered Grubee suppliers can get them to sell.
Gasbike/Kings is not on the list, bicycle-engines.com is, as well a guy in Florida.
I don't carry 2-stroke parts, even the good stuff, but the crap stuff performance has nothing to do with the EPA, they are all the cheapest things possible and smuggled in crap, just not as smart as VW did with it's dirty ass diesel cars for years before they got caught.
My only contention here is that engines aren't purposefully UN-tuned for regulations, it's because they just don't tune them!
This is even true for 4 stroke engines though the quality is much higher they just don't set the valves right.
The difference is amazing.