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First bike problems, Please Help!

Sellner91

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Hey guys, i recently bought a 1982 cb750k and have been getting it ready for this season. i have been experiencing a few issues that i don't know what could be causing them. the first issue I'm having is that when I'm heating up the bike the idle starts to run away and get up to around 4k rpm if i let it idle on its own for about 5 minutes. also my number 2 carb has been leaking out the drain in the bowl even after adjusting the drain screw. and finally when i took it out for its first trip (longer then a 10 min ride) it began to stay out and wouldn't turn back on. i first noticed the issue when i was in fifth gear i tried to increase throttle and it wouldn't rev past 4500rpm. and when i tried the bike turned off while i was riding and would turn back on as i down shifted. after letting it sit for about 5 min she came back on again and the same thing happened and had to bring her home on a trailer. I'm new to bike but have been working with cars all my life so i do have some understandings of engines but this stuff is way over my head.i do have the dreaded pods on my carbs and from what I've been reading i know they are just a pain to deal with on these bikes but its how the bike came. i also have a 4 to 2 straight pipe exhaust on it and i know that can also be a root to my problems. i just what to hear for you guys what's my best plan of attack on figuring out this issue. i have taken the carbs out and opened them up to clean and they seem very clean already but did notice the jets are not the stock size 68 102, they said 105 125. i hope with this info you guys might be able to let me know what i should do first to try and get my bike running again.

any advice helps!

Cheers!
 
68/102 is correct for stock jetting... Never let your bike run for 5 minutes at 4,000 rpm.. after you run it for a little bit check your plugs for lean, rich, cold or hot.. that would be a good starting point because your plugs tell the story of what's happening as far as combustion.
 
Most likely not what is going on but is good info for any odd carb problems and can really cause bad running. Vac hose attached to fuel tap pulls diafram open to allow gas to carbs only when running. if rubber diafram gets old it gets rotten and when cracks occur pulls straight gas through line into the carb which is delivering vac super rich to one carb. These do rot and crack on old bikes.
 
Well I have seen people think they have a dead cylinder/carb issue... And on 750 s with the airbox isn't always the easiest thing to do if you haven't done it before... Just to find out they've got a dead plug and a cold pipe.. plugs tell the story
 
Thanks for the info guys, was a combination of improper placement of vacuum lines, wrong jetting and the jets for the primary and secondary being in the wrong spot.
 
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