78 standard takes too long to warm up between rides

[bikerphil]

Yep, I knew you meant that , I've got some that have over 80K on them, trick is to lightly tie them down under the cover so they can flex evenly, not just in one spot like the original clamp setup, YMMV

[TopCatGr58]

Hey Sam,

Well with all of the extra info you've provided in the followup posts, it does look like the PU coils are the culprits. Makes sense both with your vac. adv. hose, as well as the warmup process. While warming up, you are essentially holding the same rpm so the cent. adv. and vac. adv. don't get involved much, and so breaks in the PU wires can cause the 2-3 cylinders to not be firing. As it warms up, you tend to rev the engine which then gets the cent. and vac. adv. unit moving which then flexes the PU wires, and they THEN make contact and 2-3 start firing.

I sure hope you have great ventillation in that Basement if you're running the bike down there!?

T.C.

[Ken Talbot]

Pretty wide agreement that pick-up coil wire(s) are a likely suspect. The good thing is that it is fairly easy to diagnose.

Then, this bit of info makes me think you've also got a problem with dirty passages in the enrichment circuits:

I forgot a few details that might help analyze the problem. When I use the enricher circuit it doesn't seem to work...

With the intermittent nature of pick-up coil wire problems, you would think that once in a while they would be "good" when you are starting cold, and the bike should respond fine to the 'choke' lever operation. If enrichment never works, that's where I would go next.

[DGXSER]

Ken brings up a good point. When you were cleaning the carbs, did you get the enrichment jet in the float bowl cleaned out? Its the hole in the gasket area that brass tube in the carb body sticks into. It comes out the hole in the bottom of the carb float bowl.

If that passage is not clean, then no matter what you do up at the actual enrichment plunger, you will not get any real enrichment, at least not in the carbs where that is plugged.

[SIZZSAM]

Thank you all for your help. Biker Phil had it dead on with the pick up coil wires. His pictures are neat if you've not had the problem. I had the bike running and just barely moved one wire and it cut off. I soldered some new wire in and used the heat shrink and gave it another try. I found another on the other side that was broken inside the insulation more than the first one, fixed that one and it's good to go. When I worked for Bell we used to call that a "high open" for high resistance, some connection but would cause plenty of static on a telephone line. They are pretty hard to find because aren't completely open. I did clean the enricher circuit pretty thorough. When it's cold in the morning I'll time the warm up. It should be back to normal. Thank you again for all the help. I'll close the thread. Sam