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Just got a Colortune

niclpnut

niclpnut

Forum Mentor
Past Site Supporter
A friend of mine was cleaning out his garage yesterday (I was helping) and we found an old Colortune still in the case with a couple different adapters.

I asked him if he had ever used it, and he said it was his fathers from back in the day.

He gave it to me for helping with the cleaning. :dancing:


Well, I tried it out yesterday, and have to say....It's pretty cool.

Dialed in the fuel mixture very quickly.

I figure I was probably off about 3/4 to 1 1/4 turn on the mixture screws on a couple carbs having done the high idle setting by ear/eye, and while you can't really use it under load, you can get an idea of where your at in the different circuits.

Overall, it is pretty handy, and would recomend it to anyone thinking about getting one.


Nic
 
Just curious nic, in which direction were you off? Lean or Rich? I have a Colortune and have had questionable results. It seems when I get rid of the orange flame, I go a long way before I get the darker flame where is too lean. It seems there is almost a whole turn in without the color changing at all.
 
1948man said:
Just curious nic, in which direction were you off? Lean or Rich? I have a Colortune and have had questionable results. It seems when I get rid of the orange flame, I go a long way before I get the darker flame where is too lean. It seems there is almost a whole turn in without the color changing at all.
Click to expand...

I tuned my bike with a LM-2 and when I got down to doing the mixture adjustment, it was suprising how far I had to move the mixtrue screw before i saw anything perceptiable. The RPM method seemed much better at getting close. I think Bill told be he backs out for maximum RPM and turns back in 1/4 or 1/2 of a turn. In the end that is how I left it and can confirm that the off idle AFR was nice in the 12.5-13:1 range.

So while cute, there is so much range in screw adjustment to get a change in the flame, and then no way to quantify the flame to match the cylinders, that I find little value in the Color Tune.

The RPM method is not nearly as subjective and it is much easlier to move between cylinders in an iterative process (nothing to change except what screw you are adjusting).

If you are using it for part throttle operation it might have some value if you are on a dyno, but there are so much better things to use like an WB O2 sensor.
 
At idle you are not going to get a stable color, and the changes wont be that dramatic. I was using the Colortune around 1500-2000 rpms as per instructions and would get a more steady color.

I was rich (yellow/orange flame) and slowly turned mixture screws in, just till the yellow/white went away. plug chops confirmed I was in the right location. I thought my ear was pretty good with the highest idle meathod, but Really at a certain point, I could't tell much of a difference, and my tach didn't perceptively change much.


Also slowly pull back on the throttle. If you are set correctly you won't really see much of a color change, infact the color of the flame/spark actually will become more distinct (in my case a richer blue indicating a good mixture).

Couple other cool things i could see, was the difference between a slow and gradual throttle pull vs a quick rap. slow and gradual resulted in a constant color, while a hard, quick rap showed the spark richen briefly, then even out.

It's definately not as exact or accurate as AFR readings using a WB O2 sensor as Pos says, but like I said it can get you close. And if you can find one on the cheap (or on the free ;)) seems to be worth while.

/shrug

Nic
 
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I have a colortune & it seems to work a little differently on each bike I use it on.

It worked quite well on my old '85 550L, but not so much on my '81 750.

Like you say, it will get you close & it's kinda fun to play with!
 
niclpnut said:
At idle you are not going to get a stable color, and the changes wont be that dramatic. I was using the Colortune around 1500-2000 rpms as per instructions and would get a more steady color.

I was rich (yellow/orange flame) and slowly turned mixture screws in, just till the yellow/white went away. plug chops confirmed I was in the right location. I thought my ear was pretty good with the highest idle meathod, but Really at a certain point, I could't tell much of a difference, and my tach didn't perceptively change much.


Also slowly pull back on the throttle. If you are set correctly you won't really see much of a color change, infact the color of the flame/spark actually will become more distinct (in my case a richer blue indicating a good mixture).

Couple other cool things i could see, was the difference between a slow and gradual throttle pull vs a quick rap. slow and gradual resulted in a constant color, while a hard, quick rap showed the spark richen briefly, then even out.

It's definately not as exact or accurate as AFR readings using a WB O2 sensor as Pos says, but like I said it can get you close. And if you can find one on the cheap (or on the free ;)) seems to be worth while.

/shrug

Nic
Click to expand...

You read the direction, that must be where you went wrong :lol:.

Just kidding, I also got a cheap one with but with no directions. :o

I just found these, so I guess I better read em

http://www.gadgetjq.com/ctune.htm
 
Look what I missed by not reading the directions ;)

Poor Man's Dyno
Ideally your bike would be on a dynamometer when you're conducting these tests (except idle) so there is a load on the engine. If there's one in your neighborhood and the guy who owns it will let you make a few runs for a case of beer then by all means, go for it. There are alternatives albeit possibly dangerous ones so for the record, I didn't tell you to do this.
If you jack up the rear wheel of your bike with the front tire against something very solid like...oh, say, the washing machine then, (in theory mind you), you could sit on the bike and, engine running, let out the clutch and shift up to your top gear. And then (theoretically speaking) you could give the bike some gas running it up to a 'cruise speed' then apply some rear brake to simulate road friction and wind resistance. Obviously you wouldn't want to do this for long unless you're planning to replace the brake pads anyway. A friend can check your Colortune plug to make sure you still have a nice deep blue ignition happening in this 'cruise' mode. Doing this you'll discover that load does play a part in the engines needs and you'll end up setting your TFI (or choice of aftermarket fuel enhancement device) richer than with no load.
If (you daredevil you) you've chosen to try the poor mans dyno and all was well then you're finished! If not you probably know whether you're lean or rich so make your adjustments.
Click to expand...
 
colortune

colortune

I just saw the colortune for sale at Harbor Freight, right in the checkout isle. I recall it bein really cheap. like maybe 20 bucks or somethin. Maybe aI will get one just for ****s. My gs wont be ready to use it on for quite a while tho. follow my rebuild , yall can help me out. its at the top now 1980 gs 1100e teardown/rebuild
 
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