Yeah I understand what you're saying...it seems to be fairly decent all around...It doesn't wind up as much as the 23cc'r did but it's night and day balls wise compared to the 23cc engine...i mainly only went 29cc cause i didn't wanna go 30.5cc right off so i went with the 29 and stroker crank cause now it's a cake mod to go 30.5cc
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Yes Badz--the 29cc is the second most powerfull stock piston port engine (after the 30.5cc) in low and mid range RPM power. It does deliver a fun power curve and it is common that a 2mm stroker crank will not want to rev as far as a stock crank. That is not to much of a big deal to me beacuse I like the rest of the power curve. But the top ends do have some quality issues that have never been fixed in a bout 4 years of selling them. I can gaurantee you, If you are not using a .020" copper gasket under the cylinder, you will see some nasty wear on the intake side piston skirt, and the head kit models will show some wear on the plating at the top of the cylinder (at all four bolt hole locations) because the head design warps the top of the cylinder when the head is tightened down. They also used to have terrible plating that might be improved now, but I stopped working on them about 2 years ago for all the reasons above. I build the 30.5cc engine from a CY29 right now though, and replace the top end with my 30.5cc kit. Every one of the 29cc pistons have that nasty intake skirt wear---still.
If you interested in the future (which will probably be as soon as you take your engine apart to see if I am telling you the truth), you can buy the GP290 top end, and I can do the head mods for you for $40.00 and you can bolt that top end right on your cases, and use your 2mm crank. A .020" copper gasket under your 29cc cylinder will most likely cure the funny piston wear though. I had some really good luck with those--if you can keep them from leaking. You have to seal both sides of the copper gasket with something that does not dry to fast to get it together and cause an uneven distrabution of gasket gook, or you can run into the same problem.
When you get the cylinder back on the cases, with the spark plug out, and no flywheel, you should be able to grab the crank shaft by hand to trun the engine over, and you should feel no binding near the bottom of the storoke. If you feel binding, you will have to take the top end off, and try it again.