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Back firing white smoke through carbs?

Stabler

CB750 Addict
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When I hit the start button the starter runs strong, but I only get the occasional back firing through my carbs along with some white smoke.

I've got the blue/yellow wires from my points plate to the right coils, and them connected to cylinder 1-4 and 2-3.
Brand new coils and clear blue sparks on every plug - and new plugs.
When I drain my float bowls I get lots of fuel, which makes me think my carbs get enough fuel.
I've thoroughly cleaned my carbs and changed out the o-rings, gaskets and diaphragm. Also set the float heights according to the manual for my '78 carbs.
I've got a brand new points plate.

So, I'm thinking my timing is way off? Does that sound about right? Or is there something else I should be looking for? :confused:

Thanks, Stabler.
 
I think so.. Blue from points to 1-4 cyl.. Yellow to 2-3. Crap, I have to double check.
 
My factory wiring diagram says blue to 1-4 cylinder. Maybe swap the wires anyway and see if the wiring is wrong at the points?? I cant remember did you have the motor apart? Could you have timed the timing chain a 180 degrees off? If that was the case the it wont hurt anything but your ignition will be 180 degrees off also, just swap wires from the points to the coils.
 
When i did my cafe wireing i thought a blue wire should go to blue and yellow to yellow But mine were oposite. Had same senareo back fire through carbs white smoke but good spark on all 4 i never touched the wireing on the engine or points.
 
First run on the build right?

Need to fog your engine--put carbon build up in all the right places.
Fire engine, let run a few, turn off repeat when cooled, then repeat, then repeat a few times.
Getting all of the juices into the right place & active & ready

Like feeding a baby the first time--it just don't know what to do until you show it

My best guess--
Its good to hear the baby is crying
 
Baby? Feeding? Really? Crap, I'm fresh out off pacifiers.. Lol. But really, it makes sence. Thanks man.
 
You dont need pacifiers, you built a monster!! Need to hear it roar! Lol. Good advise though! Break it in right. Have fun! And RIDE!!!😃
 
Got it sorted! My points plate were wired backwards. Blue were yellow and vice versa.. Go figure.
Anyway, it started on the first try when I changed the cables! Built up oil pressure as well. All seems good.

Thanks for all the help guys!
 
No speeding tickets as off yet. Will have to make it through registration and inspection first..
 
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