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Lack of Power from my engine

fatoldo

CB750 Member
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Location
long island NY
1978 cb750 four k carbs.
hello all, I have rebuilt my carbs on my 78 cb750. the bike is back together and it runs. At first it had no power. then I adjusted the 4 carb screws till it seemed to have power. Rode it up and down the block a few times and all seemed fine. today, 2 months later i started the bike up. It started very easy. but after warming it up it didnt have enough power to get me up my drive way. Also one other thing. Before I started it i turned on the fuel valve. after a minute of it just sitting there gas started coming out of a hose. not sure what hose but it wasnt one of the bowl hoses.
History of the bike. I just got it last summer. it was running but again seemed to have no power which is why i took off the carbs. The bike sat since 2005 outside , uncovered till i bought it this past summer. its got 8k miles on it. it looks like hell but its all there and just needs TLC to make it nice again. I have rebuilt a carb or two on cars but never a bike. this was my first. I took them down to nothing and replaced all parts that came in the kits. As it is now, the set screws are turned out about 4 to 5 turns. It seemed to run the best this way 2 months ago. I thought it was a bit much (the4 or 5 turns out) but it seemed to like it. The original way i found the bike it was 3 turns out on the screws.

any ideas?
 
If it has set for 2 months you will probably find the jets to be partially clogged again and float needle is hung up by bad gas. Idle screws should be around 1 1/2 to 1 3/4 turns out, if not you have other issues going on. Did you sync the carbs? Did you set the float levels? Did you remember the o-rings that go in under the springs on the idle screws?
 
The more I am reading threw all the post of others here, the more I see there are more things I need to do. I did sync the carbs. I was not able to see a difference as I turned the set screws. Which makes me think there is still something wrong or something I missed. I think its time to rebuild again. I also think its out of my capability. I may research some one who does this. Bikes are all new to me. Only been riding a few years and so far they have all been brand new bikes. My bike I ride now is a Victory KingPin, fuel injected. No carbs. But im not giving up on this project bike.
 
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