New bbk started 2nd try, idled fine, now won't start

[johnwohl]

First I had a problem where I left my scooter for about 2 weeks without being run and it would not start up again no matter what I tried (replaced coil, plug boot, plug, carb) I could get it to start but it wouldn't idle for more than a little while by itself and wouldn't drive. It was like I had changed the jetting drastically but I hadn't. It was on a 32 idle jet and 80 main which was working well for me for quite some time. I'm in Fargo, ND 900ft above sea level by the way.

So I decided to start fresh and I ordered a 50mm BBK from Goofit on amazon (https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1)
as I've always had good luck with their parts in the past. I also ordered a 20mm carb from ScootersToGo, a verified genuine 20mm carb with a 20mm bore and butterfly.

I put everything together, it was very easy, no issues at all except for I thought the head studs were going to bust before I got them to 16ft lbs in like 6 steps. The piston is pointing the proper direction, the ring gaps were clocked, and the cam was put back on correctly at TDC. Those were the major points I was told to look out for. That being said I'm not above taking it all apart again. I did set the valves incorrectly at .004in instead of .04mm but I have since corrected that and it ran with the .004in setting (loud though)

It started up on the 2nd try with the jets that cvame with the 20mm carb which are 28 idle and 78 main. I have proof!

A few notes about that.

-It wouldn't start with the kick start, pretty stiff to turn over and stopped mid kick sometimes (my foot paid the price).
-It would only start with the electric start and I had to let the starter get the engine up to speed before giving just a tiny bit of gas to get it to catch and run by itself.
-The farther open the idle speed screw, the harder it is to turn over.
-When it was running, I could turn the mixture screw all the way in and it wouldn't stall

Satisfied that it at least started and idled by itself so I didn't screw anything major up, the main jet was obviously very lean and I wasn't going anywhere without changing that. I decided to forego the trial and error tuning that took me all bloody summer with the 50cc setup and avail myself of a wideband setup. Between the time it took for the wideband to get here and to get the bung welded on the pipe, which was about a week, it will no longer start, no matter what I do.

It has plenty of compression, like I said earlier it is good and stiff to kick over, but not so much that it feels stuck or anything, and it gets harder to kick the more the throttle is opened (more air to compress I suppose). I have good spark as far as I can tell. A nice blue arc on the plug when grounded to the engine. As far as I can tell I have fuel. If I pull the plug after trying to start it, it's a bit moist.

I've tried going back to the 32 idle jet with all manner of adjustments to the idle speed and mixture screws with no result other than that I notice it's harder to turn over the more the throttle is cracked open.

I've tried going back to the 18mm carb I had on that was working for a long time and no joy there either.

My starter is now pushing up daisies as it was used pretty hard all season and was having trouble turning over the 100cc at the get go and has just given up after trying to start it over and over. I have one on order.

I tried starter fluid into the intake vacuum nipple (lol, nipple) but that was after my starter died so it's not doing anything with trying to kick start it.

Any ideas, questions, suggestions? It did run. Not well, but it did. Now it doesn't. What the crap.

I've come to the conclusion after messing with this thing all summer more than riding it, that these things are kind of garbage in general, and that makes me sad.