Color Tune Carb Tester - Bob Roller 10/25/06

[Justin B.]

BobRoller Posted: Wed Oct 25, 2006 5:06 pm    Post subject: Color Tune Carb Tester

Has anyone used a Colortune tool?. I have the opportunity to get my hands on one used for about $25. Carb balancing is not my strong suit, and anything that I can get to take some of the guess work out of it is worth it!

             
justinbowser Posted: Wed Oct 25, 2006 6:39 pm    Post subject:

Some people swear by them and others say they're akin to believing in those magnet "Fuel Mizer" gizmos. I think that somebody on the boxerworks forum uses one and loves it.
_________________
Justin B.
1995 R100RT
1984 R65 (Barbi's)
1982 R65LS
1981 R100RT - Nekkid!!!!
1980 R65 "RS"


MrSmart Posted: Wed Oct 25, 2006 6:47 pm    Post subject:

Careful BobbyRoll,I think you`ll find the Colourtune is for observing the Fuel/Air mixture and thus allowing you to make any necessary adjustments.
From memory I think the optimum Fuel/Air ratio is 14:1 aka the Stoichometric Ratio.
I think the more appropriate instrument for Your balancing act would be the Morgan Carbtune.

www.carbtune.com

Never used either of them yet but the increasingly rough transition from tickover to throttle-on is surely a sign of trouble ahead...




airhead Posted: Wed Oct 25, 2006 7:53 pm    Post subject:

I've had one for about 25-30 years. Used it on my Beetles. Tried it on the Beemer, and it works fine, it's just that finding the optimum idle mix is so easy I now only do it by ear.
You adjust idle mix till the yellow flame just turns blue. If it doesn't have instructions and you still get it, I'll scan them and send to you. It's not for carb balancing per se, but I suppose can help in the long run by getting both sides mixtures set, though when you do one side, the other will change slightly so you may be going back and forth!!
Bill....................


BobRoller Posted: Wed Oct 25, 2006 8:42 pm    Post subject:

I sould have stated that a little differently, I need to get the idle mixture correct. The annual registration process, requires that the bike go through emissions testing, and the bike is close to not passing, as of the last test I was within 10% of not passing. I tried bringing the idle speed up so it wasn't running on the idle circuit, but the person performing the test wouldn't do the test, due to the fact that the bike was not at idle.


Semper Gumby Posted: Wed Oct 25, 2006 9:20 pm    Post subject: Colortune.

Hi Bob,

Love the colortune. Takes the guess work out. You could set the idle mix on the lean side of the chemically correct mixture for you emissions test and then when its done go back and set it on the rich side for drivability.

There are three colors and two transition points.

Yellow - Rich
Yellow to Blue - Transition from rich to Chemically correct.
Blue - Chemically Correct range (I think about 1/3rd of a turn on the idle screw)
Blue to White - Transition from Chemically correct to Lean
White - Lean.

I have mine set within about 1/16 of a turn on the rich side the blue zone. Keeps the popping down to a minimum when you close the throttle and slow down.

When you crack the throttle you can see the Bings run rich (yellow) as the engine accelerates and then return to blue as engine rpm stabilizes. You can see and verify there is spark.

I use it every time I do a tunup. Heck I even used it to set the mixture on a lawnmower and a neighbor's 30 year old go-cart (set both idle and throttle on)!!!

It is a cool tool to have on your peg board!!!! Cool


BobRoller Posted: Thu Oct 26, 2006 9:32 am    Post subject:

Thanks for the replies, I wasn't sure how well this tool worked, or if it was even worth the time and effort. Looks like everything is there, but there is a small bottle of solvent for cleaning the unit after use, and it is dry.


airhead Posted: Fri Oct 27, 2006 12:04 am    Post subject:

Don't worry, mine dried out years ago and I never even got to use it. Methylated spirits or alchohol will clean it if needs be, but really, unless you are running it extended in an overly rich engine (which you shouldn't do anyway) you probably will never need to clean the window.
Bill............................


BobRoller Posted: Thu Nov 09, 2006 4:57 pm    Post subject:

Recieved the Colortune in the mail today, one question that is not covered too clearly in the instructions, how tight do you torque the sparkplug adapter viewer tool?


airhead Posted: Fri Nov 10, 2006 6:54 am    Post subject:

I have always just screwed it till it bottoms out, then tighten half one flat. It really doesn't have to be super tight, or torqued to normal specs as it's only in a short time. Also, overtightening and trying to loosen when it's hot might damage the window. You would soon tell if it's leaking and need to be tweeked slightly.

Bill....................

[Justin B.]

BobRoller Posted: Fri Nov 10, 2006 11:53 am    Post subject:

Thanks airhead as usual. It is kind of interesting the troubleshooting that is possible using this tool. Things that you would only be guessing at, not really knowing what was going on inside the combustion chamber.


MrRiden Posted: Fri Nov 10, 2006 1:48 pm    Post subject: color tune Carb Tester

Sounds like the Color Tune is for adjusting mixture I'll have to Google it. For now a handy little gizmo for balance that I love can be found here http://www.powerchutes.com/manometer.asp
I get the idle balanced then run it up to 3k and adjust the pull on the cables to make sure both slides (butterflys) open together. I spent a few dollars more on my balancer, opting for a bright yellow ruler and nylon straps to secure the tubing.
Rich


BobRoller Posted: Fri Nov 10, 2006 2:25 pm    Post subject:

Rich, what did you use as a resevoir for the oil?


airhead Posted: Fri Nov 10, 2006 5:36 pm    Post subject:

The manometer (tubing) is the only reservoir for the oil. You only half fill, or at least fill the tube till it's reaching about halfway up the backplane. I used ATF fluid as the red stands out against the white backplane, which incidentally doesn't really need measurement graduations in this use, you are only trying to bring the levels to status quo. I used some plastic flashing left over from putting up some walling and cable tied the tube to it.
Please don't use mercury (even if you could get it) as it's extremely dangerous and libel to spill. You can use thicker oils to dampen the oscillations, but really ATF or power steering fluid is more than enough. DON'T be tempted to use water as if really out of balance it can be sucked into the carb, not something you need to be concerned with if an oil.
Mine's been used for a few years now and just hangs in the workshop till needed, and I've never had to add any more oil to it.

Bill.................


Emiller Posted: Fri Nov 10, 2006 11:12 pm    Post subject:

My comparitive manometer no longer works right, after I carelessly allowed one of the loops of hose to contact the header on the Triumph. You can waste a lot of time trying to get them to balance that way....


 


airhead Posted: Sat Nov 11, 2006 12:54 am    Post subject:

Ha Ha, I'm not the only one!!! My loops of tubing are now a few hundred mm shorter than they originally were (fortunately, or maybe otherwise, I made them extra long). Only noticed something was up after I almost started to suck the oil on one side towards the engine, which I stopped before it did. I thought I had been careful with the routing over the handlebars, but swinging them side to side to make sure the cables weren't under tension under full lock must have had one side slip onto the header. I now secure them with a bungee strap well out of the way.

Bill...........................


MrRiden Posted: Sat Nov 11, 2006 6:06 pm    Post subject: comparative manometer

Yes as stated there is no reservoir other than a loop of tubing at the end. This little device does not measure inches of vacuum at all but the difference in vacuum between the two intakes. for an accurate reading of manifold vacuum you still need some type of calibrated instrument and it is a good idea to check each side with one to get a relative idea of how close they are before you start. Once you confirm that each side is within the ball park, oh say within 10% of spec (a figure I just pulled out of.....) you can proceed to fine tune with this comparative manometer. as I stated previously I like to set the idle stop screws then run the engine up to 3-3.5k and adjust the cable pull at the carb to make sure each of the mighty cylinders is doing its part. I've always lacked a way to measure relative mixture other than doing a 'plug chop' and reading the color of the plugs. The Gunson gas analyzer is a bit out of my range but I'd like to add the color tune to my pegboard. We need to do everything possible to squeez all the Pferdestärken out of our Wee M Ws.
Mind those hot pipes!!
Rich