Topic: No spark, no run and baffled

[robvangulik]

You try to write it in Dutch?

[mr.brandon]

Hey. Thanks for all the feedback.. to the two gentlemen discussing wire soldering vs. Crimping. I appreciate the debate but would also greatly appreciate it being started on a different thread. We all have our own ways that we like to have things done and trying to convince another of a technique other than the ones that they have used and grown to be fond of for a number of years is better.. well, you get where I'm headin' (I hope) but, at this point, the point is both WAY of the initial topic and more importantly moot. Again, I genuinely do appreciate the discussion but, I'm still working on the initial problem. I'm going to try and switch out the condensors in a bit and I will get back to the thread and let you all know. I will also check the non-running voltage at the points as suggested earlier.. if anyone knows the proper way to do the points condensor check (test) that I had spoke about earlier,  pls let me know as, I believe the condensors are both good that I'm swapping but have no way to be 100% other than what I was told was good. Thanks again all, I will get back at some point today.  B

[Tracksnblades1]

This may be what you’ve heard about…
You may find it helpful. It’s a simple quickie check.
It’s not going to let you see how it works at 8k rpm, but it’s a cheap start..

You can search “how to test a capacitor” also..

https://www.google.com/search?q=point+condeser+test&ie=UTF-8&oe=UTF-8&hl=en-us&client=safari#fpstate=ive&vld=cid:ab780eaf,vid:gg2emZ91mxI

[Tracksnblades1]

Brandon,
I would still verify that you have a full 12volts at the two point wires “first”..
Something happened.

These bikes have been idling in backed up traffic on hot days with no fans before and still made it home.
You posted it was running good before you shut it off…I’m not saying both your condensers didn’t suddenly die at exactly the same time. However I think it would be odd unless someone was welding or heli-arcing on it…

The intermittent problems tend to be tougher to track down than when it just dead…

[mr.brandon]

Hey, I'm 12.10 volts at the points ( ignition on, not running). I replaced both capacitors and... vòila!, spark is back on all 4! Still haven't got it started but that was only about 4 min. After getting spark return.  I also started messing with the sync again after it was perfect,  pls don't ask me why so, I will have to get that 1/16 or 1/8 drill bit on out (can't remember which one... I have the 657b's on my '74 cb750k  and, the curved side of the slides on the inside of the carb does go facing the rear (air filter side) of the bike correct? And the 1/16th bit (I think) must go in on the flat side (engine side)? Correct about ALL this (1/16th size, curved side direction of placement)? And I do know that the idle screw adjust must be backed all the way out before the bit is inserted in each carb. Just so nobody has to waist  the time explaining. Thanks for all the help guys, I think I'm on the good-road. Just to have to figure why it's not firing now. But for today, good progress.

[HondaMan]

I have found the Chinese-made Daiichi condensors to be made from a thin plastic sheet with thin foil as an insulator. After they get well heated (about 200 degrees F) by the engine, the plastic sheet ripples and melts. This either shorts or opens (when the spot-welded wire joint breaks off the plate) the condensor. If it shorts, it becomes about 40 ohms (in the 2 test units I had) and if it just breaks off the wire the points spark excessively - from having no condensors.

Either way, the Chinese-made condensors usually only last one or two engine heat cycles, and the above sequence of events happens. You will find these in the market as 'no name' condensors (no markings on them) or "Daiichi" brand without the 3-leaf-like emblem: the ones with the 3-leaf emblem from Daiichi were made in Japan Daiichi until about 2012 or so, when they went to Taiwan and then China. The Taiwan versions stamped the 3-leaf symbol on the bottom of the condensor's can: some of those actually work.

If the 3-leaf symbol is missing but it says "Daiichi" then it is counterfeit parts from China - which don't work, often right out of their package.