Not Starting/ magneto to blame?

duluthmuffler · Posted: April 14, 2008, 10:06 pm Post subject: Not Starting/ magneto to blame?

I'm at my limit of knowledge, and I need your help. Long and short of it. I could start my bike in 0-10 deg. F... in February... Then I got all antsy and wanted to go to a permanent magnet set-up. In the process, tearing everything down to the bones (wiring harness off).. mostly out of boredom because I couldn't ride... I got the magneto set-up and was trying to get it to work... it wouldn't... So I'm in this process of trying to get it started... and I'm not having any luck. I'm back to everything stock... with everything hooked up... and its still not wanting to live for me. I did have like about 10 single tick-overs. Almost like it wanted to run but lacked something to actually run.

Here's my list.... what am I obviously missing....

New Gas
3 carb cleanings. - (more, and more thorough to come)
Starter Fluid doesn't work.
Battery charged up to 14.
Timing is good.
Points triggers sent to correct coils. (One coil gets hot... one doesn't) Red Haring?
multimeter shows spiking voltage at plug cap.
Plugs fire... mostly / weak spark (what does a good spark look like?)

I'm guessing that fuel is good. Plugs are wet. When I was having slightly better luck, I could get the cylinder to be to rich, then come back off it, and have better luck.

Is it possible that when I was trying to get my magneto set-up to work, I fried something? I did use the CDI- thingy that came with the unit. It was from a Suzuki TM250....

It seems more possible that something isn't plugged together correctly.. But there is power supply, and even spark......

I'm reaching in the dark... Any help?
This is a 77.

Thank you.

Retiredgentleman

Weak spark................Is the points gap set correct? Make sure there is no oil or grease on your points.
Battery voltage has to go through main fuse/ignition fuse/ ignition switch and kill switch to get to the coils. Any or all of these may have a voltage drop caused by corrosion/bad connection etc.. Measure the voltage at the coils..............should have about .5 volts less than your battery voltage. Those stock coils are weak so they need all the primary voltage they can get.

duluthmuffler

THANKS!! I'll try it.

jimmythetrucker · Full Member Joined: Mar 12, 2008 Posts: 1283

Good spark is big and blue. Bad spark is little and red or yellow. Wet plugs mean your choke is working OR that your carb float bowls are overflowing (for whatever reason).

To eliminate the possibility of float-bowl overflow, turn the petcocks OFF and disconnect the fuel lines from the carbs. Remove the spark plugs and go get drunk. Let the bike sit overnight with no plugs in it. That will dry the cylinders for you.

Next day install NEW plugs, and hook up the plug wires. With the ignition switch ON and the throttle at idle, choke the bike and jump on the kickstarter once. If it doesn't start, jump on the starter again. If it STILL doesn't start, un-choke the bike, open the throttle wide, and kick the starter four or five times. If the machine still doesn't start, I'd start looking for ignition problems.

If everything works as it's supposed to work, your Japanese bike should start at idle. If your Japanese bike doesn't start at idle, your Japanese bike is imperfectly tuned or has another problem of some sort (and boy, am I gonna catch hell for THAT assertion!).

royfisk

Jimmies right it should start with just the enrichiner (choke as some call it). I beleive something is up with the coils. I havent used this kit but cdi and points use 2 differant coils,differant ohms readings there. get rid of the cdi thing, test your coils as describbed in your service manual.

Now I am going to take jimmies place and exp;ain the differance between a choke and a enrichiner and catch flack.
#1) Choke. Choke is when you use a butterfly to actually restrict air from the ventura, henceing the word choke

#2) enrichiner. Is a circuit in the carburator which when open adds more fuel to the starting mixture. henceing the word enrichiner

#3) americans didnt understand this so the japaneese motorcycle companies to simplyfy things put something americans did understand on the cables. (the word CHOKE) .
ok kiddies thats it for todays history lessons.

jimmythetrucker · Full Member Joined: Mar 12, 2008 Posts: 1283

That's right, Roy. He also said that one coil gets hot but the other doesn't. There's something wrong there, I'd almost bet on it.

royfisk

The coil that is hot is going to ground somewhere

duluthmuffler

Voltage difference was 1v at coils....
Carbs were fine. I know because IT RUNS! LOUD!

So embarrassing....
y points were plugged into the coils... and the condenser... to itself more or less.

Thanks guys. 100% awesome advice.

Gees what an oversight.....Always consult your manual.
I'll let you guys know how the magneto project goes here....

OHHH just thought of this...
One hot coil makes sense.... it was the one that was currently being triggered!

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