Now here's the thing. I had been running my puch e50 with a stock setup for awhile. I had shaved the head, trimmed the piston skirt, and was using a 14mm bing with a hollowed out stock airbox. The stock exhaust pipe had been de-restricted as well. I was hitting 29-32 pretty consistently with 16x40 gearing.
Then, I put on my old airsal kit that I had seized last year. I had since ordered a new ring for it, and decided to give it a go. Compression was almost nil, and it was no better than stock off the line, but around 20mph it would wake the hell up and scream up to about 36. I'm talking tugging the handlebars almost out of my hands screaming too.
However, it's the off the line that I want. So I ordered a vintage 75cc kit. It looks like an old athena kit, but I'll be asking the seller tomorrow to be sure. It's definitely aluminum with a chrome or nikasil lining. Only one piston ring, and bigger ports all around than the airsal had.
I put that on my bike, gave it the whole heat cycle and break in procedure, and opened it up for the first time tonight. Dissapointment.
The thing does pull a _tiny_ bit better than my stock (stock!) setup, but it doesn't even pull as hard as the airsal with next to no compression. This thing has tons of it though. The fins resonate something fierce too. It will pull slightly better than stock up to 31, and that's it. It will not go past it. I'm using the same jetting setup as I had used on the 70cc airsal, and even tried going to the next size up with no improvement. Just like the airsal did, it revs wicked fast, but even the ruined airsal outperforms it.
I must be doing something wrong. I've tried adjusting the timing, but all that did was make it ping and knock. I''ve yet to downjet, because I need to get some more plugs to get a look at the exact standing of rich to lean balance.
Has anyone else had this happen? If so, what advise do you have?