Motorcycle Repair: 1978 Honda CB750K choke, adjustable tension, plastic tubing

Question
I just bought a 1978 Honda CB750K and it runs great but when I pull the choke up it does not stay it just goes right back in, I have to hold it up until it is warmed up, is this normal, and if not how do I go about fixing the problem

Answer
Many of us who have older Hondas consider their chokes to be "semi-automatic". Whether they were designed that way on purpose or not, the choke knob usually moves back in just about when the bike no longer needs choke.

The problem is that if the cable has ben lubricated recently (and all cables need to be lubricated from time to time) the choke will go off before the engine is warmed up.

What I did for my sidecar machine that has pull knob choke (my GoldWing has a choke lever on the handlebar with adjustable tension) was cut a short piece of 1/2" plastic tubing , slit it and slip it over the narrow part of the knob. When the knob moves inward it stops when it hits the piece of tubing and I can usually pull away then. Before I get to the corner I can jiggle the knob so that it falls inside the piece of tubing and the choke opens fully.

BTW: I highly recommend joining a good forum that caters to bikes like yours. The folks at http://www.cb750c.com are a pretty good bunch.