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1991 cb750 engine running on just one side of engine ( 2 cylinders )

Jayboy74

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Hello everyone , I was able to get my bike running but its only running on the right side of the engine ( right side while sitting on the bike ) I have not had any luck finding a manual for troubleshooting so i was wondering if someone could help me out , What should i check and how should i check it? It is getting fuel so i am assuming its an electrical issue. If anyone can help me out i would appreaciate it
 
A very simple first step is to take an extra spark plug and test for spark from each wire one at a time.

Unplug the wire, plug in the loose spark plug, "holding the spark plug by the rubber boot" hold the threads against the head so you can see the plug gap (which should be set to proper specs) and crank the engine over a few times and see if you have a spark and how strong it is.
 
Thanks , dave , What brand and # plugs do you recomend? Also what are the factory plug gaps? Any idea where i can find an online manual for the 91 cb750?
 
I run the stock NGK's in my bike and they work fine even with the original dual points and a pair of old coils.

Just google "1991 cb750 service manual" and you'll scroll down until you find an online one but, if you plan on doing all your own work, the book is well worth owning.
 
Thanks dave , Bought a service manual and new plugs i just have not been able to work on her since i got them. I am going to change the plugs on my next day off , I will post updates once i am able to work on her again . Thanks again for pointing me in the right direction.
 
I had a chance to work on my bike again today. I took the tank off and put new plugs in the bike . The bike is still just running on the 2 right cylinders . It is getting spark , I sprayed a little choke cleaner into the carbs on the left side and she started hitting on all 4 for a few seconds. I find it odd that just the 2 left cylinders are not getting gas , are they connected in a way that would cause them both to not work at the same time?

I found another issue while i was working on her, My rear rim has a tiny bend in the edge , It looks like the person may have hit a curb or something. The bend is maybe 2 " long and looks like its bent about 1/4" inch outward. Do you think this can be fixed and is it small enough to be safe to ride? My bike has the stock alum one piece wheels on it
 
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