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Carb Sync Tool?

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Webb

Webb

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For downdraught (DGV) Webers, I mean. I know Moss sells a synchronizer with a round base on it, but the inlets to my Webers are square. Any ideas where I could get a square one, or a way that I could make a round peg fit in a square hole?
 
Since you own a Honda CB750, you may be familiar with the different vacuum gauge sets that are used to sync those carbs. Use them!!! After all, it's the same principal.
 
That Twinmax looks like a pretty nice tool, however, would it work if I just hooked my vacuum gauge up to the vacuum ports on each Weber? It's late so I'm not going outside to test it now (nice 30 deg weather we have), but would the carbs pull enough vacuum individually to register accurately?
 
Webb said:
That Twinmax looks like a pretty nice tool, however, would it work if I just hooked my vacuum gauge up to the vacuum ports on each Weber? It's late so I'm not going outside to test it now (nice 30 deg weather we have), but would the carbs pull enough vacuum individually to register accurately?
Click to expand...

You'd have to have a fine scale on your gauge and then move back and forth quickly, and would probably never get it much closer than by listening to the intake through a length of 1/2 heater hose. The TwinMax works by having a vacuum tied to each carb declaring one of them to be the standard, and then adjusting the other until the needle centers. You can get the scale fine enough on a twin motorcycle to see the pulses on the scale.
 
Yeah, I just went outside and tried the vac gauge and it was far to low to measure accurately. Looks like I'll have to spring for the Twinmax. Should come in handy when I rebuild the 750's carbs in a few weeks too.
 
For what it's worth a car club friend told me how to do it with a short piece of hose. One end in your ear, and the other end at the carb. Listen to the pitch, and make the 2 carbs match. Seems wayyyy too easy for me. Local club guys said I could go ahead and buy a tool for syncing, but the piece of hose/tubing works just as well. They know more than I.

But the hose trick does work,...even for me.
 
Do you just take the filters off and stick the end of the hose near the throat of the carb?
 
yes take the filters off and poke the end of the tube in the intake 1/4 inch ,making sure it's the same position on each carb.and adjust to get same level of hiss from each carb-throat.But using a proper multi carb balancer is more precise .
 
Does it matter how long the hose itself is? What do you use, like 2 feet worth of hose, or less than that?
 
Doesn't matter how long the hose is, just long enough to reach from the carb to your ear. In a pinch, you can just lean down and stick your ear next to the carb (tho it's much harder that way).

But I have to say that, for the SUs on a TR3, I much prefer the SU tool kit synchronizer; as it makes it easy to compare flow in real time, so you can see how far the linkage deflects between idle and off-idle. With car, you can get them both synchronized. Of course, that doesn't apply to Webb's DGVs.
 
The hose trick worked great for idle. I'm actually amazed at how easy it was to match them up. Just like tuning a guitar. That and the timing light have probably been the best two things I've ever bought for my car. I've had it for 3 years now, and it has never run this good. I know all the old-timers are sitting back in the computer chairs and laughing, but that's ok by me. No more hesitation, no more shaking, way more power...it's great.
 
/bcforum/images/%%GRAEMLIN_URL%%/iagree.gif
Webb
Let 'em laugh.
You learned something today, and that's what it is all about.
Now you can say "I made this car run like a clock"
Good Job!!!
/bcforum/images/%%GRAEMLIN_URL%%/hammer.gif
Dave
 
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