Carb Sync

[Coyote]

Correct me if I'm wrong please. Doesn't step 5 wipe out what you accomplish in step 2?

[pearljam724]

All you have to do to synchronize any set of carbs is use a homemade feeler gauge under each slide to assure they are all opening and closing at the same exact moment. Any diameter tubing, etc. will work. Place it flat on the bottom of the intake bell mouth. Close or open the slides by the throttle linkage. Assuring they open and close at the same measurement. Takes 5 to 10 minutes. If the bike does not want to idle. You simply adjust the linkage to allow the slides to open a little further to induce more air after they are synched to one another. If the bike idles too fast, you need less air. Hence, closing the slides a little further to reduce air. Do that until proper idle rpm is accomplished. Air increases idle, unless it's so great that it chokes a motor of gasoline. Causing it to shut off. There's somewhat of a fine line of having too much or too little air introduced into the intake. That's why the factory recommended measurements are suggested in your post. It has to fall in between those measurements when you adjust the throttle linkage.

[Coyote]

I performed step 2 using thread wires. I used a .031 as a go and a .040 as a no go. Securely locked down and rising exactly together. But step 5 confuses me as it's telling me to move the adjustment again by aligning one slide even with the top of the carb bore and adjust the others to it. So if one is off and you have to adjust the linkage to make it match, step 2 will now be off by the amount you moved it in step 5. I'm going to omit step 5. If step 2 is performed accurately, 5 is automatic.

[Craig380]

I've always synced mine visually by making sure the slide cutouts (facing the airbox) all disappear into the carb body at the same time ... it's easy to get this accurate, and then the slide heights are pretty evenly matched at idle settings too.

I'd rather have a good accurate synch of the slides at wide throttle openings than at idle

[Cliff]

The slide synchronization is just a starting point.
Then after everything is on and the bike is running, you have to balance the carbs.!!
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CARBURETOR ADJUSTMENT - 38 39
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http://www.3cyl.com/tripleed/suzigtcarb/39.jpg" onclick="window.open(this.href);return false;
The slide synchronization is just a starting point.

[titan performance]

I do it as Craig described...simple. Surely the position of the slide at rest is determined by the idle screw, not the adjuster at the top?

[tz375]

Almost.

It depends on whether the slide is hanging on the cable.

There are many ways to do it and one is to use a carb balancing tool, but all I do is to make sure all 2/3/4 slides start to rise at exactly the same time and clear throat at exactly the same time.

Carb balancing tries to get the airflow through each carb to be close enough to identical but teh problem with that is that all 3 cylinders are rarely identical in terms of compression or timing or bore wear or piston clearance etc and all those change how hard an intake sucks air.

One school of though is that's all that matters and the other is that is irrelevant.

I do it mechanically watching slides lift. Your technique may vary.

[Cliff]

"Carb balancing tries to get the airflow through each carb to be close enough to identical but teh problem with that is that all 3 cylinders are rarely identical in terms of compression or timing or bore wear or piston clearance etc and all those change how hard an intake sucks air."
Carb synchronizing gets the air flow through each carb close to identical IF all three cylinders ARE identical, but like you said they rarely are! You have to "sync" the carbs first to make sure that ALL the slides are at the same position. That's your starting point. The bike will run, but it'll run better after you balance the carbs. Each cylinder is different, like you said! It may only take 1/2 - 1/4 turn on each throttle rod adjustment to balance them, but it makes the world of difference in the performance! Don't look at this as one three cylinder engine, it's not. It's three single cylinder engines working together!

[yeadon_m]

I agree with the posts noting that perfect bench-synch may or may not mean real-world 3 cylinder balance. I've been lucky in that generally it does, but totally agree its 3 single cylinder motors bolted together.
Coyotes post though does raise the question, with ganged carbs, wth Suzuki meant by step 5. There is no question that having fiddled with the adjusters on each carb arm to set the slides the same at closed throttle, if you mess with those at WOT, you lose what you just gained. As little as 0.2mm difference (1/4 turn) at idle might make a noticeable difference to idling sweetness. That 0.2mm won't matter a darn at WOT. So I bias my bench synch to idle. I can but rarely do find I need to tweak much to synch once back on the bike.
What was intended by Suzuki in step 5 I still don't understand either!
Cheers,
Mike