Problem with my Honda CD200 Roadmaster

i have recently rebuilt the engine on my Honda CD200 Roadmaster. it is a 200cc parallel twin. i rode it for about 5 kms. its a pretty old machine, i think several ppl rode it before i got my hands on it. The bike was junk when i purchased it. rebuilt the engine, put on a new camchain, bearings, oilseals, changed the cylinders, pistons, rings, valves, everything.

The problem that im facing is that although the bike starts, it runs only on one cylinder. the right cylinder is working fine. the left cylinder isnt. the right cylinder blows off hot exhausts from the exhaust pipes, but the left exhaust pipe blows out a cool breeze of air. the plug on the left cylinder is firing because there is stream of spark flowing to the connecting end of the plug when i take off the plug cap and bring the wire close to the connecting tip of the plug. removing the plug cap on the left cylinder does not kill the engine. but removing the plug cap of the right cylinder kills the engine. the bike also knocks while riding.

Further problems include the neutral light which always stays on. so i have to ease the clutch off to check if im on neutral.

This make is getting rare these days and in a few years itll turn into an antique item. help me out puhleez.

P.S the plug on the left cylinder gets fouled. the right one is a nice tan color. thanks  

I've rebuilt my CD200's engine as well, only to be faced with the same problem. We've also come across the same issue with my girlfriend's CD. It turned out to be the condenser that packed up. A nice workaround to this is to omit the condenser, and replace it with a Velleman Transistor Ignition DIY kit (K2543). Modification for 6V setup is a case of swapping out 4 resistors. Easy to install, less wear on points, much better and more consistent spark, and it prevents fouling by better combustion.