Jonway Xpressway 250cc No Start By kcohen67 (Read 420 times)

[kcohen67]

I bought a Jonway Y250T as a project bike. I have WHITE Spark, GOOD Starter, and good gas, but STILL it won't start.
I replaced CDI, coil & Stator, battery and spark plug. I rebuilt the Carburetor and head.I got it to start, but the Idle was rough and white smoke poured from the exhaust. I noticed the flange the carburetor was connected to had a broken broken bolt so I extracted the bolt, resealed the flange, now it won't start at all. Tried adjusting Carburetor air/flow mixture. After about the fourth cranking cycle I hear the Carburetor cough a bit, but that's it. Any suggestions?

Dropbox link to MORE photos and Video


In this video at LEAST I had it running. Now NOTHING.

[cyborg]

Introduce gas into the carb and you should hav it pop,,,if it does you know it's a carb problem

[kcohen67]

I've since rebuilt the top of the engine. Now this is what it does ths. After top half rebuild.<---- CLICK HERE

[kz1000st]

It's spinning way too fast. I would recheck the valve timing again and make sure it's not 180 degrees out of sync. My CN 250 doesn't spin any where near that fast on starting. Check compression too.

[kcohen67]

I removed the timing port screw on the side of right side of the engine, made sure the the cylinder was dead top and the lined up with the mark inside the engine. Outside of doing that, I don't don't know any other way to check for perfect timing.

[kz1000st]

When you just lined everything up did you check the valve adjustment? It just sounded like the engine is spinning too fast like there's no compression. A partially opened valve would do that.