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Discussion Starter #1
I just bought a 1974 honda CL360. The motor was actually replaced with a cj360 but I believe the engines and carbs are very similar. The main problem I am having now is the bike seems to be running bogged down. It will still ride and I can get up to about 50mph but it seems like there is very little power. However,every once in a while, the bike will randomly take off and run very strong for about 20-30 seconds. It shot from 50mph to about 75 really quickly. Then it will start to run with little power again. I have all of that'll I exhaust and air filters on. I just don't know what could be causing it to randomly start running really strong for short bursts. It has happened I'm both 3rd and 5th gear. I'd appreciate any help!! Thanks!
 

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Sounds like float problems, causing the fuel levels to rise and fall. Or, spark issues, causing one side to drop out. Check the spark plugs for color; perhaps put new ones in, and try again, in case you have a cracked insulator. Also, check to see that both pipes are heating up the same; one of those remote temperature measuring devices makes this a lot easier.
 

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I've changed the spark plugs and went to a hotter plug also. And I don't think it's the spark plug because when one is fouled, the bike will only run for about 15 seconds then shut off. Unless it cuts out at higher rpms? Could it be the pilot screw adjustment? And I took the carbs off and the floats aren't sticking. Is there something else I should check for with the floats?
 

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I've changed the spark plugs and went to a hotter plug also. And I don't think it's the spark plug because when one is fouled, the bike will only run for about 15 seconds then shut off. Unless it cuts out at higher rpms? Could it be the pilot screw adjustment? And I took the carbs off and the floats aren't sticking. Is there something else I should check for with the floats?
What is important is to actually look at the plugs, as they will tell a lot about why the engine isn't running correctly. Does one foul faster than the other? Is one wet, black, white?

As for the floats, there is a proper height adjustment, so the carburetors can mix in the fuel at the right ratio. Another thing to check is the sync between the throttles; the old-school way on these bikes was to have someone judge the exhaust pressure and flow from each pipe, while the throttle grip is slowly turned, after the same check to get the idle settings in sync.
 

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Discussion Starter #6
What is important is to actually look at the plugs, as they will tell a lot about why the engine isn't running correctly. Does one foul faster than the other? Is one wet, black, white?

As for the floats, there is a proper height adjustment, so the carburetors can mix in the fuel at the right ratio. Another thing to check is the sync between the throttles; the old-school way on these bikes was to have someone judge the exhaust pressure and flow from each pipe, while the throttle grip is slowly turned, after the same check to get the idle settings in sync.
I've checked both the plugs. The right cylinder was dry with a black and kind of gray color. The left was all black and had more residue on it. It might be a small oil leak in the left cylinder. But I believe this means it is running rich?

I've also checked the pressure coming from each pipe and they seem to be about the same.

Thanks!!
 

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The Honda 350s are notorious for running like dog crap if the carbs are even a little out of synch. Since they have a manual choke butterfly, make sure they are full off and not moving. Carefully check the float levels (wet-set) and the slide diaphragms for tears or binding on the slides. They should pass the "clunk test" (when released the slides should not drag, but "clunk" firmly into seated position) If they don't let me know & I can steer you in the right direction. After a THOROUGH (meaning ALL air passages cleaned and CONFIRMED clear by blowing Gumout Jet Spray through them) cleaning, including emulsion tubes, these carbs should be synched using a set of synch gauges. When you get 'em right you'll know.
 

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Do yourself a favor and check the spark on the plugs, they use resistor plugs and the 74 had a habit of burning out the plugs and the spark would not come from the electrode but from the ground.
 

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Discussion Starter #9
Thanks for everyone's help!! I took the carbs off and cleaned them pretty well and made sure all the passageways were clear. I also adjusted to float heights a bit. It's like a new bike!
 
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