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Discussion Starter · #1 ·
Just picked up a 1973 CB350G. Over the first couple days I got the bike running, idle adjusted and the like.

Yesterday and today though I have been plagued with not being able to get the thing to start. Once I started do the normal checks, have compression, have fuel supply with enough weight to feed the carbs, but NO SPARK.

So being that I am very green on playing with bikes here I am.

What I have tried so far and what I have found...

Measure between the primary coil wires and get 4.1 ohms each - from what I have read this is good
Measure between primary (black w/ white stripe) and hi voltage wire (plug wire) and get one measuring 20k ohm and the other 18k ohm - Is this bad? - I thought I read that they should measure between 5k and 11k ohm range. Mine are obviously quite a bit higher!

Last measurement that I have found to try is: Key on, measure primary to ground and should get something in the neighborhood of 12v I measured 6.xxV IS this bad and if so where do I start looking?

One last question: I have searched and not found anything thats clear enough for me... How do I test the rectifier? I need some explicit instructions with this!

Thanks guys and looking forward to getting to know you all!

Justin
 

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Measure the voltage at the battery, if less than around 11.5 volts(key on) charge up the battery and/or replace it if necessary. You need more than just 6 volts at the coils before you can even start troubleshooting the ignition.

Once that's done and the bike is running you need to find out if it's charging.

Then make sure there is no drain on the battery while the bike is shut off
 

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Discussion Starter · #4 ·
Thanks! I got it running... I can't tell you exactly what changed, but I do believe it is related to the black w/ white striped wire that Y's off to both coils ( I believe this is the hot wire to the coils). I found that the connector is split down one side and needs to be replaced.

Does anyone make a new wiring harness for the bikes or were there too many options to make this possible?

Thanks again!

Justin
 

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You would be better off just replacing the connectors. Not a hard task at all.
I changed all of mine with 5 bucks. look for 14,16 G bullet connectors and replace them. That should do the trick.
 

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While you're at it, give some thought to replacing any old style (metric) fuse holders, and wiring in the newer style automotive blade fuse holder. Blade fuses are available at nearly every gas station in case of trouble.. ;)


GB :mrgreen:
 
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