So Im trying to balance my carbs by using two vacuum gauges but when i adjust the screw between the 1st and 2nd carb it seems to have no effect at all on my readings. The 1st carb is sitting around 15 hg in's and the 2nd is at about 4 hg in's. Am I missing something?

 

This is going to sound dumb but are you sure you are adjusting the correct screw?

 

Not a dumb question, I considered it. I consulted my manual and it seem like this can be the only screw between the carbs. Also when I push on the screw the bike revs. Weird?

 

Pushing on the screw will rev the bike.

I guess make sure your on the right vaccum taps for starter. One out of the 4 carbs is engine only and not actually a carb. You use that one as the base and adjust all the other carbs to that one.

IIRC on the honda, the left pair of carbs sync to each other and then the right pair of carbs get sync'd toeach other and then.... sync the left pair as a pair to the right pair as a pair using the 'center' adjustment screw.

I've never done it with only 2 gauges so I can't comment on what that might complicate. Only that it is a super PRECISE adjustment and you can make it worse just as easy as you can make it better so be aware if your set up is not right.

I actually do mine over 2 days. I set them and then ride for a while, let it sit over night and hit them again the following day to get them perfect but 'Im kinda OCD about my bike tunes fwiw.

 

Thanks for the advice. I wish I could even ride my bike, I think my carbs are so out of sync that if I even try to get it gas it will die. The carbs are completely clean so I dont know what else it could be.


If anyone else had any advice or tips it would be greatly appreciated.

 

Mmm,that doesn't seem likey.

Either something clogged in the idle circuit or an excessively lean condition for some reason

Are all cylinders firing? Start it from cold and you can literally grab hold of the headers where the pipe leaves the engine on each pipe and feel each cylinder warm up. That will give you an idea right away of which cylinders are firing, in what order or even at all.

But my guess is its something other than balancing.

 

+1 on what zaqwert6 is saying. Can't stress enough though to be careful checking the exhaust pipe temps though. They go from room temp to melt your skin off very quickly.

As for synching the carburetors, If the engine is dying with a little throttle, then they need to be cleaned again. When you take the carbs off and look at them from the intake side so you can see the butterfly plate. As you move the throttle (by twisting the place where the cables attach), all of the butterflies should appear to open and close at the same time. If they "Appear" to do this, then the sync is close enough for the engine to run and accelerate just fine.

 

If you are only using 2 guages, get a four-way aquarium manifold.
Hook one guage to the reference carb (the one without an idle-adjust screw)
and the other guage to the manifold and then distribute it to the other 3 carbs.
Then. you can switch on/off between the others, as you zero in. Each adjustment
to an individual carb will affect the other's draw, so you will need to go back and
forth a few times to get it righteous.

Hope this helps, Ern

 

Thanks for the advice guys. I tried using Dirt's method of looking at the butter fly valves, screwing them all the way in and then back out but I didnt notice much of a change :/ Then my carbs started making a clicking and hanging up when ever I pulled the throttle. Ill have to wait till Wednesday to figure this all out once school is over with.

Ill let you guys know if this works or if I run into any other problems.

 

So, when you cleaned your carburetors, did you separate them from each other ? If so, there are springs that sit underneath the synchronization screws. If they're not installed right, then you won't be able to adjust the sync.