where do i hook up a carb sync tool to my 70 honda cb350?

Question

i am thinking of making a sync tool and or buying one. but i have no idea where to hook it up. i have looked in the clymer manual but nothing of a vac nipple or anthing for the doing this procedure in the book. just moniter the exhaust. its a kei hin carbor somethung like that

Answer 1

Buy one much easier and more accurate. The tool goes over the throat of the carb to measure the air flow. You Check each carb with it adjusting each one til they're all even. Lots of time to get it right. Remember to do it at idle and at 1500 to 2000 rpm

Answer 2

2 cylinder?
--Pointing down, behind the float bowls is a pipe. That may be what you're looking for. But then again, it may not LOL
--Back in the days, carb sync was a foriegn concept to OEM manufactures. When tool comapanies came up with the idea of syncronizing carbs, they had to come up with a way to hook up the gauges. They came up with the idea of using the same valve that's used to fill footballs, basketballs and soccer balls. A thin gauged tube (like a hypodernic needle) would be inserted through the rubber intake manifold.
--The simplest way to sync a two cylinder engine is to put your hands at the ends of each muffler while the bike is running. Adjust the carbs until you feel the same exhaust pressure coming out of each muffler.
--That method is used today by the best, not wanting to waste their time hooking up gauges.

Answer 3

Honda Cb350 Carburetor

Answer 4

Those old bikes did not have vacuum taps, but, you could install some. I have a Chinese motorcycle with no vacuum ports so I drilled and tapped a 5mm hole right into the side of the carb. When not using the synch tool I install very short 5mm screws into the holes with blue loctite, works perfectly. Alternatively, if you have space anywhere else on the intake tract you could drill there instead.
The quick and easy way we used to do it was to touch the throttle lever on one side and watch the throttle lever on the other side, bump the throttle grip with the other hand, its easy to get a sense of which one is lifting first. Because those carbs are not connected in a rack like most modern carbs it will be difficult to get them dead on, and if you do they won't stay that way very long. You kinda have to put up with good enough.

Answer 5

You'd have to install nipples on the boots of that old thing. It's not really worth it. A little trial and error and a good ear is better. Just get the adjustments to where each cylinder drops out with the same amount of downward turning.

Answer 6

If it cuts out Change the O-rings on the main jet.Also check diaphrams for pin holes.