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All right, just replaced the intake manifold gasket. Temporarily since I used a Mitsubishi truck gasket to do the job (the auto parts store didn't have the O Ring). Not the problem.

Looks like my issue lies with the little flying saucer looking bit at the back of the carb (engine side). Looking at the service manual, it's the air cutoff valve. I'll try replacing the lines to and from it as well as the o ring inside otherwise not sure where to source one of those suckers.

Slowly but surely I'm getting somewhere.

Something I noticed though, when I had the spark plug out, I turned the engine over to feel for compression. With my finger over the hole, it actually was sucking my finger into the cylinder. Is this normal? Now I think I did this before I adjusted the valves again, but I had adjusted them once and didn't think it should be doing that. Maybe I'm wrong... Wouldn't be a first. I've just never had a cylinder suck my finger in.

Ok, this was after I redid the exhaust but before I checked my valve lash and found my spark plug was incredibly loose (I MAY have forgotten to tighten it when putting everything back together). I did the spraying the vac lines with ether as you'd suggested and I find that the engine picks up speed when I spray the little round piece closes to the engine on top of the carb. I'm not sure if it's the intake itself that's sucking it in or if it's the gasket on the intake, or the vacuum piece on top of the carb towards the back (close to the engine). I have a new intake manifold gasket. I may go ahead and pull the intake off and replace the gasket just to be sure it isn't the problem. I won't be able to today since it's about to rain but that's the current plan.

Also when I redid the valves and tightened the spark plug, it seemed to not pop as much coming down from full throttle but that may have been because it wasn't fully warmed up. Will give it some more testing tomorrow.

All right. I'll give the exhaust another shot. Maybe I tightened one side too much when I installed it the first time. I have to adjust it a bit anyways for the muffler . I'll give those both a shot tomorrow don't want to wake people tonight testing it out at midnight. I'll take another video when I get it done to see what, if any, difference it makes.

Stock air box. There's a filter inside the airbox and I mean a regular style filter not the foam sheet the 50cc's use. But the filter is also stock.

Ok I'll appologize right now if the sound is off from the video. I guess youtube doesn't handle MP4 well and that's what the Flip records in. Anyways, here's the link for the video giving the sounds that it's making and (hopefully) syncing what I'm doing to the sounds.

The temp gauge stayed low the whole time though. Never above 3 bars.

Ok so those following the previous thread, I've FINALLY managed to get her running. I've taken a quick few runs and noticed some things that worry me slightly.

First off, when she's cold, she doesn't want to rev up at all. Give her gas and she stalls out. Once warmed up she runs just fine and the entire time she idles great.

Second, when running (I only took her for a couple of miles nothing incredibly long yet since she's not inspected and missing a mirror) when I get up to speed and let off the throttle she starts popping from the exhaust. I'm assuming I'm running lean or rich (I can't remember which it is) so I'm assuming I need either a carb adjustment or I need a new air filter (maybe both?).

And finally, when at a dead stop I give it some throttle but the response leaves something to be desired. The engine picks up, slows for a second, then revs up normal.

I have a feeling all these symptoms are from the same issue I just need to figure out how to fix it. I've gone through the service manual and they're a little vague on some things and carb settings they tell you that it's set from the factory nothing more is needed.

So where am I going wrong? Is my timing off a tooth? Is it the carb? Valve lash wrong? Where did I goof?