73 CB750 Carb Jetting and Idle Problems

gatorforge

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So, this is it, the last thing to do on my build before the bike is up and running, and it is stumping me. I rebuilt the carbs when I rebuilt the top end of the engine, and thoroughly cleaned them and bench synced them at the time. I am running pod filters and a 4-1 exhaust, and when I first fired the bike, it needed no choke and was idling at about 4k RPM. I checked the idle screw, and it was barely touching the carb body, so it was not causing the high idle. The stock original Keihin carbs were jetted with 110 main and 40 slow. I ordered a selection of jets, and rejeted the bike 120 main and 42 slow to compensate for the pods and exhaust. The bike required the choke to fire, but with the choke all the way on it was idling at about 2k. As soon as I moved the choke lever down to the off position, it revved to 5k. Rejeting to larger jets, should have brought the idle down by equalizing the air fuel ratio, but seems to have made the situation worse, any information on getting this corrected would be helpful. I'm so close to being done, I just want to get over this last hurdle.
Thanks

Also, I know many people on here hate pod filters. Thats fine. That is the route I have chosen to go, and I understand it does mean that there are complications like this.
 

gatorforge

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So with your advice, I got this one sorted out, I had adjusted the idle screw a second time when it would not fire and forgotten about it doh!. Got it up and drivable, made one short pass on it, and it stalled. Seemed to be running rich, so I got it up and going again and adjusted mix, but couldn't get it to run for prolonged periods. Jetted back down and the problem has persisted. Put in new plugs, and the bike cranks over well, but wont start. Tried choke on and off, but it just wont catch. Any suggestions?

Thanks,
Lance
 

dirtdigger

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Pull the plugs are they wet? If not your not getting fuel. Try giving it a little shot of carb cleaner or just a bit of starting fluid or if you have a little squirt bottle give each carb a squirt of fuel and see if it fires.
 
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