Motorcycle Repair: Dead cylinder

Question
I have just been given a Honda CB400T that has been sitting for about 3 years or more.

I put in a new battery, drained the old gas and refilled with fresh gas.  It started up fairly quickly, but it is only running on the right cylinder.  Right side header pipe very hot, Left side is cold.  Pulled the plug and installed a good one from another running bike, the one I pulled had gasoline all over it, but no fouling of oil or carbon....just gas.
No difference from replacement plug.....................condition same.

I'm thinking maybe a bad plug wire or coil????

Terry

Oregon

Answer
Hello Terry,

First, check left cylinder for spark.
To do that, attach a spare spark-plug to the left spark-plug cap, place it on the cylinder-head so the metal shell makes contact and crank the engine to see if there is spark.
If not, get back to me.
DO NOT remove the left plug while carrying out this test.
Any fuel left in the cylinder could splash out and ignite by spare plug sparking.

Since the bike has been sitting for so long, for sure the carburettors have to be cleaned.
Especially the fuel jets get clogged by gasoline residue.

Clean them thoroughly and get back to me if anything goes wrong.

Best Regards,
Lazaros.