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1979 750k full throttle and gas over flow issue??

BabaYaga

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New to the cb750 boys but an average mechanic. I got this 79 cb750k 3 weeks ago and it ran horrible. I have receipts from the motor rebuild 2 years ago and the carb rebuild from 8 months ago from a solid mechanic. The owner I got it from left gas in the carb for about 6 months until I got it. They never rode the bike so it has about 100 miles on it since the complete overhaul of the motor. Ok... So I took the carbs apart for a total clean and replaced tons of stuff. Most was still brand new and I reused some stuff. All new gaskets and o rings and pilots screws. So I didn't put new jets in the carbs because they were clean and larger then the stock jets I purchased. The jets in there were 70 main and 105 secondary. Put the whole thing back together. Now everything else I did as well on the bike. New throttle cable with grips, new bars and bar ends, new plugs gapped at .30 (ngk), new air filters for carbs, new air filter for crank case vent, new petcock. I left the larger jets thinking more fuel the better, and I gapped the plugs at .30 because I talked to a guy that said a little bit bigger gap helps on creating a larger spark. I know stock was up to .28, and the ones I took out were gapped at .22-.23. So now knowing that let me tell you what happened. I got it out back together last night and started it up.... Perfect... Ran like a brand new bike!!! Idled a little fast but I hadn't touched that yet (not really fast just faster then idle should be). Then after about 1 minute of letting it idle and talking to my brother about it I decided to do some small quick throttle revs to check that as well. Oh yea I lubed the push and pull cables also. Now I hit it with about 3-4 quick small revs and all of a sudden the bike goes into a full rev??!!! I immediately shut it off. Waited a second and tried it again. As soon as start up happened it went full rev immediately. I traced the cables and made sure nothing was having them up and tightened the cable lock nut to make sure. Started again.... Same thing. So I decided today I'll take all tension off the throttle cable and start it up to rule out the cable sticking. But after this issue last night I noticed a good bit of has under the bike. Did a quick scout and found no gas on the motor but found it was coming from the over flow tubes. Not sure on which one or how many. Now I don't know a ton about carbs but I did find some info that told me I should have checked the float height. I also didn't change the float needles (I have new ones) because the ones it had in it literally looked brand new. And the carb wasn't dirty at all when i took it apart. Like I said he had about 100 miles (if that) on the bike since the rebuild and about 10 miles since the carb rebuild 8 months ago. I still did a complete carb clean but figured the new looking stuff was fine. Any advice and help is welcome. I chose this forum because I've for good advice off old threads from here. Thanks in advance boys
 
I forgot to say I set the new pilot screws to 1 1/2 turns out of all the way in. And I didn't touch the sync screws. I just unclipped them and re-clipped upon assemble.
 
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