Motorcycle Repair: Honda CB160, honda cb160, ebay auctions

Question
Bill,
I have a 1966 Honda CB160 sitting in my garage. I got it running
for a short while, but the battery keeps going dead.  What could
be causing that?  Also there is what looks like black oil on the
spark plugs when I remove them after the bike has run for a few
minutes.  Does that usually mean the cylinders need to be
rebored or that the rings are just worn out?
Rob

Answer
Rob, you have to determine the condition of the engine before you go too far along. Check compression to see if it is around 160-psi or so. If so and the bike doesn't have more than about 15k miles on it, then you may have something to work with, as-is.
These bikes are battery powered ignition, so the battery has to be good to begin with and fully charged. If it seems to just go down overnight, then the rectifier may well be shorted out internally. You can construct replacements from Radio Shack parts (email me through my website for details) or check Ebay auctions for a replacement. The wiring has to be in good condition and all the connectors clean and shiny.
The black could just be unburned fuel from the weak spark situation, so clean them or replace them after you have sorted out the charging system and carburetors/fuel system condition.
Fuel system has to be clean from gas cap to carb float bowl.
Ignition timing has to be checked after you remove the point plate to be sure that the mechanical spark advancer is not frozen from sitting. Once that is verified, you can lube the point cam, adjust the gap to maximum .012-.014" and then move the point plate around until the points just open at the F mark alignment on the flywheel.
Check timing and valve adjustment when bike is straight up on the center stand. There is oil in the stator cover, so put a pan underneath before you remove the left crankshaft cover.
Manuals are generally available from Ebay sources or from www.motorcyclememories.com or www.helminc.com

Bill Silver