Moby 50v won't start. I'm out of ideas

I got this 1978 motobecane 50v 25mph model. So I have blue spark, timing set to 2mm btdc, point set to .35mm, installed a 14.12 sha using 54 jet, all lights work when I pedal it, and I haven't officially checked compression but it feels normal. When I pedal it it sounds like it wants to start but just won't fire up. It will run if i keep pedaling it but dies as soon as I stop. I have the stock 10mm intake and I don't know if that's the problem. Also checked the bonding strap and it's ok. I plan on hardwiring it and putting a new bonding strap in. Besides that I don't know what to do. Ordering some circlip pliers to rebuild and have a bendy intake coming in thought that might help with the new 12mm intake. Any ideas?

Re: Moby 50v won't start. I'm out of ideas

Oh I put a dry plug in and pedaled it up and gas is getting to the plug. Don't know if it's the right amount but from what I understood these aren't too picky on jet sizes.

Re: Moby 50v won't start. I'm out of ideas

Search out how to do a leakdown test and check if the carter can hold a vacuum. You might have a vacuum leak which is diluting the air-fuel charge too much.

Re: Moby 50v won't start. I'm out of ideas

I read about the leak down test plan on doing that tomorrow. Would the 10mm intake prevent the 14.12 sha from working right? I have a bendy intake coming in. will it mount to my bike easily?

Re: Moby 50v won't start. I'm out of ideas

Where would I get the seals? I know the size and all but don't know any machinist shops or industrial suppliers. Anywhere only that has them. Will the one on moped junkyard fit a av7?

Re: Moby 50v won't start. I'm out of ideas

treatlandtv.com has eveything for av7's

Re: Moby 50v won't start. I'm out of ideas

check the ground wires on the internal mag coils. I had exact same symptoms, it was ground wire on internal coil came unwelded, soldered it back.

Re: Moby 50v won't start. I'm out of ideas

The ground on the ignition coil is soldered to the metal next to it. I checked continuity from the hot to ground and it read. If that is the ground for the coil. Is there a diagram or schematic for the 12v flywheel. Mine has been messed with before me and i'm confused on grounding wires and how to connect up my new condenser. There was a external already mounted to mine with it connected to my points. The old one was also on there connected to what looked like my ground on the 6v coil. I pulled the internal out and have a new condenser to replace the external. Also confused where to wire that. The points? Any help on this is greatly appreciated. Also went to my local bearings supplier and ordered new seals. They didnt have NAK so i got some other brand. Singled lipped. It was 15-21-4. Would that work? they asked double or singled lipped i didnt really know.

Re: Moby 50v won't start. I'm out of ideas

So I moved the we condenser to the ht coil and removed the two mounted to my flywheel ( one inside, one mounted to the original) and cleaned the points. I'm cleaning out the tank while waiting for my new seals and bearing that treat finally got instock. I can't imagine after I replace all the gaskets and seals it won't start. But I'll see.

Re: Moby 50v won't start. I'm out of ideas

Gromosaurus Rex - Brad Pitt /

so....any progress ? interested in the condenser issue

Re: Moby 50v won't start. I'm out of ideas

♣Slew Foot♣ /

check the wire under the points thats where mine went bad it was bare and arcing

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