Colortune, I don't think I am impressed . . .

[V7Goose]

OK, I tried out the Colortune yesterday, and I don't think I am impressed at all. My plan was to use the Colortune on one cylinder, then compare the CO % of that cylinder with the others using the exhaust gas analyzer. Since I cannot find any published specifications from Yamaha for the right CO level on this engine, that seemed like a good way to approach it.

 

The problem is that the Colortune does not seem very specific. I could turn the fuel mixture screw a LONG way in either direction without seeing any change in the color of the flame. After turning it out a lot I did eventually see a yellowish flame as I should, and if I turned it in far enough I would eventually see it begin missing a lot (mostly just a weak spark), but there was a huge range between those two points where all the sparks looked the same. I eventually just turned it in to the ultra lean point, then turned it out just a bit past where the spark seemed to be regular without any missing. The interesting part was that when I compared this setting with the original position of the mixture screw, it was almost identical! Coincidence? I have no idea.

 

One other problem that may have contributed to the lack of a clear setting was that the spark was constantly jumping from the top of the Colortune plug to the engine, potentially causing a lot of misfires that would affect what I could see. But since this engine seems to have a dual-fire ignition with a waste spark in every cycle, there is no way to be sure how many of those arcs were really causing a misfire.

 

I was doing this inside my garage on an overcast day where I thought the light was about right to easily read the Colortune. In addition, I was working on the left rear cylinder where it was very easy to look right down on the plug and get a clear view of the spark without needing to use their mirror attachment. Finally, I purchased the 12mm Colortune specifically for this bike instead of the generic 14mm unit with a 12mm adapter. I am glad I did this now, since the 14mm with an adapter would have had the Colortune plug sitting much further out of the cylinder, and I would be wondering if maybe that was why I found it so inaccurate.

 

I have not yet tried out the exhaust gas analyzer, but I'll let y'all know how that goes soon. In the mean time, I would be interested in any responses from others that have actually used the Colortune. What did you think?

Goose

[Condor]

FWIW, I think that's why setting the idle screws out 2.5 +/- turns seems to be a good generic setting. I don't have a clue about the ColorTune, but can you increase the R's to see what color flame you get when up at highway R's?? That might be a better way to judge what the motor is doing with the current jetting???

[pegscraper]

That kind of behavior from the mixture screws is typical of emissions era carburetors, bike or automotive. The idle circuit is so leaned out and so restrictive via other fuel supply orifices in the circuit that the mixture screws themselves have hardly any effect on the mixture. The idea was to keep people from making it too rich and covering up other problems by backing the screws way out. But running too lean like they keep doing increases other emissions that aren't good either.

 

Yes, the spark plugs in this engine fire every time the piston comes to TDC, not just every other time at the combustion stroke. I don't know if this was intended on purpose for emissions reasons or if it is a side effect of a crank triggered ignition. Each trigger point comes around at every crank revolution, and there's no easy way to eliminate the one that isn't needed. It doesn't seem to hurt much, so they let it go. I don't know for which reason the plugs fire this way.

[BEER30]

Perhaps , you need to consult Muffinman . He performed a Color-tune on my scoot which led to better performance on my scoot . The color I believe you need to achieve is a Munson burner blue . I saw the change in the color before and after Muffinman did his thing , but do not know my screws to tell which and how much to turn .

Before the color-tune , my MPG were moderate , but after then increased and didn't get the black residue on the tips of my exhaust as before. Only mods to my scoot was change the exhaust from stock to Baron 4-2-4 Nasty Boys . Everything else is stock . After the Colortune , we did a Carbtune . Coming home from Sledgehammers house where we did the Color-tune , I got 200 miles off a tank of fuel , 15-20 mph headwinds , average 75mph . That was this spring . Now I get riding 2 up , pulling the BEERCART , average speed 70-ish about 33 mpg . More when going slower speeds or 1-up. I'm happy with the Color-tune .

 

 

BEER30

[MiCarl]

I use the color tune plugs, but not on the Venture so far. My observations:

 

The 12mm plug is really hard to see. The throat of the thing is so narrow the flame isn't readily visible.

 

Arcing to the head is a problem on water cooled machines in general. On air cooled machines the plug isn't buried so tight and it works better.

 

The color range I've always observed was yellow-blue-blue-blue-blue-dark when it misses. I usually set them up by richening up until I have a yellow flame, then leaning out to where the yellow just disappears. This is a tad rich at idle, but helps out at higher speeds where everything built after 82 is inherently lean.

[CrazyHorse]

I dont care for the colortune either. Too hard to use on these motors with deep wells. I noticed hardly any change with my original 37.5 mixture screws but with the original 42.5 screw of 1983 I noticed a change but I use the rpm method instead of my colortune.

[N3FOL]

Does anyone have a link to this particular product? I have no idea at all what the Colortune is all about and what benefit it is on my Venture.

[mraf]

Does anyone have a link to this particular product? I have no idea at all what the Colortune is all about and what benefit it is on my Venture.

 

Google colortune kit and you will find a whole bunch of imformation on this product.

[N3FOL]

ok, will do that. Why didn't I think about that route.

[Squidley]

I'm with you Goose, I wasn't real impressed with it either. Mine broke at Floyds maintenance day as they are a PITA to use on an RSV. They exchanged it easily enough with no hassles. I found the same thing as you in the fact that there was a large gray area of how much to turn the screws. I'll probably try it again, but I would love to see a detailed how to video of how it's "Supposed" to work

[CrazyHorse]

I'm with you Goose, I wasn't real impressed with it either. Mine broke at Floyds maintenance day as they are a PITA to use on an RSV. They exchanged it easily enough with no hassles. I found the same thing as you in the fact that there was a large gray area of how much to turn the screws. I'll probably try it again, but I would love to see a detailed how to video of how it's "Supposed" to work

 

I think these things are better suited to be used on Harleys where you can access the spark plug easily. I'll probably put mine up on ebay.

[Captainkirk]

I use the color tune plugs, but not on the Venture so far. My observations:

 

The 12mm plug is really hard to see. The throat of the thing is so narrow the flame isn't readily visible.

 

Arcing to the head is a problem on water cooled machines in general. On air cooled machines the plug isn't buried so tight and it works better.

 

The color range I've always observed was yellow-blue-blue-blue-blue-dark when it misses. I usually set them up by richening up until I have a yellow flame, then leaning out to where the yellow just disappears. This is a tad rich at idle, but helps out at higher speeds where everything built after 82 is inherently lean.

 

Say, don't I know you from somewhere?

[Captainkirk]

The Colortune should, as mentioned earlier, burn a deep cobalt (Bunsen Burner) blue. If your flame is yellow-ish, you either have jetting issues (plugged, wrong size, etc) or an induction leak somewhere. What you just explained to me was that you backed the screws out to (and past) max richness adjustment, and you were STILL running too lean. Hmmm, maybe there's something to this ColorTune stuff after all?

How are your spark plugs coloring after all the adjustment? If you're really too rich, they'll be black & sooty after a few minutes of idling time. Methinks there are other issues afoot.

[djh3]

I recently picked up a colortune for a decent price. Problem is the spark plug thing is a 14mm. Now I have seen some sort of adapter gizmo on e-bay from them but mentiones something about compression gauge also. So I got my compression gauge out and sure enough the colortune part threads in nicely. But it would put the electrode part2.5 inches above the cyl. I'm thinking this aint going to do me a bit of good huh?

[MikeWa]

I'm with Goose. The exhaust gas analyzer is the best way to go. Especially if it is an infra red type analyzer. The old Wheatstone bridge CO /AF ratio testers are just to slow and not all that accurate. With a good infra red exhaust analyzer you can also compare HC readings which will tell you for sure if everything is working ok or not. Some of the modern ones let you have it hooked up while you take a test ride and print a graph when you get back. I wish more motorcycle shops would learn how to use them.

 

Mike

[k9cottage]

i first got mine when i had a kawasaki z1300 6 [bloody] mixture screws it turned a nightmare into a 15 minute job i have the 14mm with 10mm and 12mm adapters. sold the z13 7 years ago and the new owner still brings it back for tuneups .have used it on the rsv and it is great the 2 front cylinders are a bit of a pain and i don't use the mirror tube i use a bike mirror

[djh3]

So does the 12mm adapter look like just sort of a nut with threads on the bottom to thread into cyl? My adapter is sort of like that but the tube is probably over 2.5" long and I dont think its going to work as an adapter for the colortune. Its made for my compression gauge which dont care how long of a adapter it has. Dang more money.

[Yammer Dan]

Pass the popcorn....

[ACE50]

Man, I wish I had seen this thread before I ordered a colortune. Same issues as Goose had. Seems a waste on these bikes.

 

I'm thinking I just need to do the valve adjustment (27K) as it seems a little rough at times and a carb sych doesn't help it.

[muaymendez1]

Man, I wish I had seen this thread before I ordered a colortune. Same issues as Goose had. Seems a waste on these bikes.

 

I'm thinking I just need to do the valve adjustment (27K) as it seems a little rough at times and a carb sych doesn't help it.

You can always rent them to me. Maybe a few rentals will make your money back

[V7Goose]

I'd be very happy to sell mine- been used just the one time.

Goose

[Guest tx2sturgis]

 

Yes, the spark plugs in this engine fire every time the piston comes to TDC, not just every other time at the combustion stroke. I don't know if this was intended on purpose for emissions reasons or if it is a side effect of a crank triggered ignition. Each trigger point comes around at every crank revolution, and there's no easy way to eliminate the one that isn't needed. It doesn't seem to hurt much, so they let it go. I don't know for which reason the plugs fire this way.

 

That is called 'wasted spark' and its fairly common on small engines. HD engines included. It seems to be a cost cutting, and engineering compromise, rather than emissions related.

 

It's considered harmless.

 

 

 

[ACE50]

That is called 'wasted spark' and its fairly common on small engines. HD engines included. It seems to be a cost cutting, and engineering compromise, rather than emissions related.

 

It's considered harmless.

 

 

 

 

Harmless..........your wearing out the sparkplug twice as fast!!!!

[Yammer Dan]

I will buy another one soon.

[Rick Haywood]

Do the color tune at night or at least cover you and the front of the bike to make it as dark as possible. N matter what when muffin man did mine my bike ran so much better'