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Carb Sync tool

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Just passing on a little note. When using two or more synchronizers, Always find a common source and check each unit on that one source, such as one carburetor or whatever. That way you can compensate for any variable readings. These things aren't made by rocket scientists and regardless of the make, check them for match if using more than one at a time.
 
2wrench said:
If I remember right, with my BP270 cam from bpnorthwest, I set the
intake at .012 and the exhaust at .014.

So by "valve clearence," do you mean resetting and/or verifying the
valves to these same specs?

When/how soon is this to be done?

Valve clearnce and timing I think I can get past; but carb mixture and
synch could prove a bit more of a challenge. I am willing, of course,
to go for the synch tools heretofore mentioned as A: It would be great
to know how to tune the car in toto; and B: Any investment would pay dividends
by not having to pay shop fees at roughly $100.00 per hour.....

So I'm willing to learn. Do I qualify a worthy student??? Kind of like the
tranny, though -- if it is likely to be way over my head, I'm willing to
concede. Only you experts can clearly discern. Your input, please.

PS: Still waiting till tommorrow to order my rotor parts.
PSSS: Don't mean to hyjack the thread.
Click to expand...
2wrench, just check the valves clearence at the #'s you were given. Follow the procedure given in the Manuals. You don't need to understand the sequence, just follow it, like a cookbook receipe.
Plenty of time later to think about why it works.
Set the ignition timing. Don't be afraid of this. the engine itself will let you know when you hit the sweet spot. But there are aids such as a timing light to get you in the ballpark, close enough for the next step.
Carb mixture. Like setting the timing by ear, practice makes perfect.
Good instructions for this are in the Manuals.
My suggestion is to lift the carb's air valve 1/8 inch and observe the engine's reaction. If it speeds up you are too rich. If it stalls you are too lean. A slight speed increase is ok, but rpms should settle back down.
Play with it, get a feel for it, before you make your final determination.
Synchronize. The heater hose to the ear works and is shown as THE method in most Manuals. Just try it to see what it's all about. You'll hear the hissss of air. That's what you are trying to balance.
Or you can get that tool that Paul showed. Don't waste $ on the Unisyn. I use a sthethoscope in the way you would with the heater hose.
Important here is to have the linkage loose between the 2 carbs so they operate independently during the process. Retighten the linkage carefully so as to maintain the balance you set,
These are all things the owner should learn to do as they are the fundamental elements to maintaining a smooth running engine. AND a good starting point to troubleshoot problems should they occur.
 
Friends of Triumph racing has a page of historic photos at
https://www.fot-racing.com/historic/index.html

Down at the bottom are photos of Kas Kastner's tuning kit.

Oh look:

air%20flow.jpg
 
Howdy Paul,

"Thanx" for the info. Real good info & item(s) to have.

Russ & probably the Rest of the Gang here!
 
I still have my Unisyn from the early 70's. hated it then, don't have to use it now.

Although, I will admit that I used it to verify the readings on the SK after I first got it. The SK is just too quick and simple to use for a lazy guy like me.
 
Stupid question-

The Buckeye Triumph carb tuning directions
show the Unisys with the tube vertical.
The Kas photo shows the same tube horizontal.

Which on is correct?

Also, I spoke with Banjo about the tube listening
method. What do I listen for?

thanks,
Dale
 
Dale: I have always seen the unisyn used with the tube vertical.

If you use the hose you want to listen to the rush of air into the carbs to be equal in volume.
 
If you do put the hose to your ear, in order to get good results (and it is possible) place the hose in the same relative spot on each carb AND equally important, the same place on your ear for each carb.
When you get close to the balance point, the difference is subtle, so you have to be consistant.
A cheap stethoscope with the amplifyer removed is much easier to manipulate.
 
Tinster said:
The Buckeye Triumph carb tuning directions show the Unisys with the tube vertical.
The Kas photo shows the same tube horizontal.

Which on is correct?
Click to expand...
The angle of the tube basically sets the sensitivity of the unit, so the more nearly horizontal, the more sensitive the ball is. Using it with the tube vertical is why so many people have to crank the venturi adjustment way down (which the instructions say to leave alone) and then turn the idle rpm up to keep from killing the engine.
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Also, I spoke with Banjo about the tube listening method. What do I listen for?[/QUOTE]Basically for the hiss to be equally loud (indicating the flow is the same). You don't even really need the hose, I've done an adequate job just holding my ear near the carb and using a hand to control the distance.
Point being, the balance doesn't have to be all that close for the engine to run well.
 
I use the same tool Brosky, but with a pvc elbow from a hardware store, in the plumbing department. That way I hook the elbow on the face of the carb(oh by the way I glued an oring on the facing lip of the elbow) and can move it from carb to carb very easily. I prefer it, as no need to "adjust" the opening, like the Tinster has encountered.


Works fine on the Hitachi's on my Yamaha FJ1200, the SU's on the Z car, the Webers on the other Z car(GTO 250 kit car) the Strombergs on several 6's, the Webers on the other 6 and SK's when they were on another 6.... And have used them at tech sessions on a XK150...

I prefer the simplicity, accuracy and ease of balance measurement...
 
If I remember right, I got mine from Pegasus, or Pierce manifolds. It's been so long can't remember.
 
With the triple ZS set-up, I adjust thecarb connectors and cable linkage to ensure I get full WOT on all three carbs at the same time. That's all I worry about. The idle pretty falls into place automatically. The way I see it, it's a mechanically locked system, and you can't program it to have equillinear travel for the (2 or 3) carbs across the entire operating range.
You can set it for perfectly smooth idling,andthen hope that they all reacch WOT simultaneously (if at all). or set it up to ensure WOT on all carbs and let the idle fall where it may, which is what I do.
Maybe I'm all wet, but that's how I look at it, FWIW.

Tom

P.S. MAN! I had a really rough time correcting some spelling errors on this post.I kept losing letters and spaces, etc., so it looks like a slow 2nd grader's writing. Maybe it's the wine I had with dinner.
 
Sync-ing the carbs just assures that the carbs have the same starting point on the way to WOT. The adjustment is made with the throttle stop screws.
 
I have used the rubber hose method for 50 years with my TR3A. My hos is a bit of old garden hose about 18" long. If one carb makes a "hiss" and the other is out of sync., it will "hoose". With the clamp between the two carbs loose, I adjust one of the idle screws till they both sound like "hiss" when listening at this end of the hose. Then I tighten the clamp screws between the two carbs (on my TR3A) and re-check the "hiss". Many times, after doing this correctly, the tightening of that center clamp between the two carbs puts the "hiss" out for one of the carbs, So you loosen the screw and start again till it's all tight and the "hiss" is the same for both carbs.
 
Dang I hate when it does that. It hisses the heck out of me
 
Don Elliott said:
Then I tighten the clamp screws between the two carbs (on my TR3A) and re-check the "hiss". Many times, after doing this correctly, the tightening of that center clamp between the two carbs puts the "hiss" out for one of the carbs, So you loosen the screw and start again till it's all tight and the "hiss" is the same for both carbs.
Click to expand...

That sure can happen. Just enough to make a difference.
 
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