My buddy had a question regarding his bike

[Gun]

It's not a 60's honda, but he was hoping some of you would have some info for him as other forums haven't helped his search for info.

"Hey there guys,

First off, the bike is a 1974 Honda CB360 w/ not a spot of rust and only 6,000 original miles. This bike literally sat in an old mans garage for 30 years. I am the first to restore it. Never been dropped or taken apart. Each piece I take off this bike still has some of the factory plastic attached to it (seat, levers, etc..)

So here's what is going on and also what I've done.

Currently the bike idles, responds and drives really nice. There are no hesitations all the way up to redline on this thing. It seems to be tuned in really well and it's a fast little bike.

THE PROBLEM:

The right side exhaust sort of gallops and sputs a little at idle and if I drive it for about ten minutes, the right side stops running. Spark still goes on the right side, but I don't know what's making it stop running. The left side still runs great and strong and everything.

A few things about it and what I've done to restore it:

I have adjusted the points 3 times through troubleshooting/doubting myself. Spot on every time
I have cleaned the carb by dipping it in one of those cans of carb cleaner.
I rebuilt the carb with a kit w/ new jets, air screws and gaskets.
I Kreemed the tank.
I replaced the petcock with a NOS one.
I am 1.25 turns out on the air/fuel mix screw on both sides which I'm told is the stock setting.
I replaced the diaphragm on the right side carb. Both are nice and hole/rip free now. They both glide nice.
The bike has aftermarket pipes on it that look nice and everything, but seem to have less baffle than the original pipes did. Previous owner put them on.
I have aftermarket air filters on it, so I might be running a little bit rich but the problem I'm having currently is only in the right side and no amount of air/fuel screw turning is changing it.

SOLUTION:

I don't quite know what to do. I try to keep from assuming things are tuned right unless I've done it myself.
My last idea would be to check the valves. I have never done this before so I don't know if the problem I'm having could be caused by the valves being out of spec.

Help please? Ideas?"

from ryan via gun
thanks guys

[mike horvath]

Ryan,
Possibly the carb float is sticking...? Does this bike use a fuel crossover line? Maybe next time the left side quits, remove the carb bowl and check for fuel. Also, when it quits, open the gas cap and see if that cures the flow problem. My Scrambler sometimes will quit on one side when I'm down near reserve and flipping the lever to "reserve" allows full flow. Check it out.
Hope this helps.

Mike

[busaken]

said you rebuilt the carbs. with aftermarket kit. did you check the pilots and main jets to see if the are the same size as orginials? some of the kits out there have similar jets but are not the same jet sizes. did your kit come with needles. some of the needles have different tapers. you kreem the tank. did you removed the gas cap and kreem the tank or was the cap left on while you kreem the tank? said there as aftermarket mufflers and air filter. your jetting will need to be changed. maybe 1-2 sizes up on pilots maybe 1 up on the mains. how is the compression. did you give the bike a compression test. even though the bike sat for years. not good for the valves or cylinder and rings. good idea to give it a compression check. process of elimination. also check for intake leak between carb and cylinder head

[bedrich7]

said you rebuilt the carbs. with aftermarket kit. did you check the pilots and main jets to see if the are the same size as orginials? some of the kits out there have similar jets but are not the same jet sizes. did your kit come with needles. some of the needles have different tapers. you kreem the tank. did you removed the gas cap and kreem the tank or was the cap left on while you kreem the tank? said there as aftermarket mufflers and air filter. your jetting will need to be changed. maybe 1-2 sizes up on pilots maybe 1 up on the mains. how is the compression. did you give the bike a compression test. even though the bike sat for years. not good for the valves or cylinder and rings. good idea to give it a compression check. process of elimination. also check for intake leak between carb and cylinder head

Thanks for the replies everyone! HondaTwins forum is slow to reply. You guys are on the spot.

pilots and main jets are the same size.
same needles with same tapers.
took the petcock and cap off while Kreeming tank.
haven't rejetted yet.
i'll have it compression checked
no cracks through the rubber intakes on engine to carb.

anything else? If the compression is fine and the carbs are synced fine, is it probable to assume that the valves could be out of adjustment and that is what's causing the gallop in the right side?

[17again]

As Mike mentioned above about the floats sticking.

Sometimes the aftermarket float bowl gaskets need to be trimmed, as on the Honda 160's, but I think the 360's used an o ring type.

Does not sound like a valve issue to me. Did you check for spark a the plug or spark at the wire? Could be a bad plug.

[bedrich7]

ah.. good point. I'll check my plugs. I think I got some good info from the HondaTwins.com forum. I was reading a different post and someone said this:

"I looked at the carb castings today and the Jets are in the correct position. Damn. Still flooding at 1/4 throttle. Is there a good way to sync the carbs without the use of a vac gauge? I tried to sync by matching up the amount of light filtering through the carbs holding them up to a bright light. Then I used ball berings to match the openings to where when throttle opened they both fell through at the same time. I have read that if the carbs aren't properly synched that one cylinder is constantly trying to catch up to the other and it will flood the side trying to catch up."

I'm not having exact issues this guy is, but my right cylinder is firing a little off and or something due to whatever my problem is. Looks like I've got a few things to do:

Compression Test
Sync Carbs
Check/Replace plugs to NGK's