Update: Okay, I have done compression tests on both of my bike engines. They are both China Girl PK80, 69cc/47mm cylinder/40 stroke with the short connection rod and the low wrist pin on the piston. However, the bikes have different set ups.
GT Bike--> Ported by my friend who works at a machine shop. He ported the intake/exhaust/transfer ports and decked the cylinder to .03' squish gap while using a mill. The bike is also set up with a .6cc Clone FredHead, CHD-G2 4 peddle reed valve with windowed piston, 15mm Dellorto Clone Carb (HT/RT), MZ Miami expansion pipe, FMF Powercore 2 sliencer. This engine has about 400 miles on it.
Peugeot Bike----> Purchased from Dax about 6 years ago also Duane from Dax ported the engine for me. I decked the cylinder myself using a piece of glass and sandpaper method attempting to get it to .03" squish gap. The bike has a .6cc Real Fredhead, a 15mm shorty intake, stock piston, 15mm Dellorto Clone Carb (HT/RT), Sick Bike Parts Expansion pipe. This engine has over 2000 miles on it.
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The results of the test came out:
GT--------> 158 psi
Peugeot--> 195 psi
I gotta say that the Dax engine on the Peugeot has always been just an awesome engine, once I found the right jet (#60) the thing just took off. Not only did it have awesome throttle response and a steady low idle, it has almost no chain drag, the engine sprocket seems to spin endlessly. It has got to be the best engine I have ever gotten. I had the bike running so well that I didn't want to change anything and, you know, screw it up, haha. But perhaps it's just the luck of the draw? I don't know. But I was very surprised to see a compression of 195 psi, a full 37 psi higher than the GT one and 30 psi higher than the top range that you gave me. Is that unusual?