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First hand colortune review

chuck hahn

Forum LongTimer
Past Site Supporter
Rob ( AZR ) sent me his colortune to use. I went online and read the owners manul and found a few videos of how to use it and what to look for. One site said to set the RPMS at around 2000 and see what color your getting. Yellow being to rich..bunson burner blue being just right..and bright ice white blue being too lean. I adjudted each fuel screw till i began getting a yellowish color, then backed off the screw 1/8 turn at a time till i got the nice bunson burner blue. I then ran the RPMS up to around 5 or 6,000 and watched the color to see what happened. Seems that once you get it dialed in at the 2,000 RPMS, the color stays consistent throughout the RPM ranges. So I can confidently say the thing works and i am possitive each cylinder is at its optimium settings..Thanks for the use of this cool little gadget Rob!! Heres a picture of what the bunson burner blue looks like in the cylinder.

 
Good to hear a first hand review.
A lot of people are negative about this tool which discourages others unnecessarily.
 
Jeep..I found it to be a sanp on the VMs..nowm ive heard its a bit rougher to get the CVs dialed in. But rest assured this final little bit of tuning was the cats azz. You could see the color change and actually listen to the engine smooth out oh so slightly as you went from carb to carb. I had to reset the RPMs a few times back down to 2,000..guess its sort of a combo of highest RPM method but with the added advantage of actually seeing the changes within the combustion chambers..
 
When I first started to tune these GS carbs by the fastest idle method I was always wondering "Is this right?", being a novice motorcycle mechanic, and still am, and never having worked on a four carb bike before. With this little thing it let me know things were right where they were supposed to be, a real help for a novice. Glad it's working out for you Chuck.
 
Thanks for the review Chuck, and for loaning him the Colortune Rob :)

I can't wait to get the time to put mine to use and get her running better. Very keen to get into it but I just can't get a break at the moment... it's either wrench or ride and I wanted to get the km's up for the first service before our run on the 5th Feb...
 
Cool, just an added caution?

Cool, just an added caution?

Only problem I have with mine is fiddling around with a hot plug, (ow-ow-OW!), and getting it to fit well into some of my other bikes, but it's all there in the kit. Oops, I think I had to order a 12mm adapter for a Yamaha 550 Seca.
One issue I found was that the glass is polycarbonate, and got soft when I ran it too long.
Bill
 
So it's like a spark plug with a clear part to see the combustion color? Cool!
Strange I haven't heard of that before :confused:


The only thing I do to verify tuning is correct is a "plug chop".
 
The only thing is that, with the bike sitting in the driveway, it doesn't take much throttle opening to get 2000 or 5000 RPM. In all cases you are still in the pilot circuits. On the road the needle jet/jet needle and the main jets will come into play to get those RPMs.

I think you have only tested pilot circuits.

Can you blip the throttle and see what colours you get then?

Brian
 
Brian..yes you can blip the throttle and see what happening..and i did run a few bikes WELL past the 5,000 to nearly redline levels and the flame didnt change. The only color change I got was right when you first rap the throttle to the full on position..then I got a yellowish blip ( rich situation ) which all the reading and videos indicated would be a normal reaction. Once I had really rapped the throttles up on a few bikes, I had come to the conclusion that if you tune them JUST till the yellow goes away at the 2,000 RPMS then youre pretty much dead on throughout the full ranges of the carb curcuits..Gives one a great piece of mind knowing they arent running lean and that each cylinders as close as it can be.
 
Bill..heres the solution for hot plugs and reaching into numbers 2 and 3 to get the plug started into the threads. Just a piece of vacuum hose over the end and you can feed that plug in there and be sure it is hand started and not cross threaded. I use hemostats to retrieve the hot plugs off the engine.

 
Mike..yes i did ride the 77 750 up to get oil for doing the oil change in the Hondamatic. It was a bit more snappy on the throttle response as compared to before. My thinking is that either a lean OR rich condition has some effects on the throttle responses. Rob says he doesnt need it back right away, so if you or Frank wanna throw it on your bikes I think we can do that.
 
Just for chits and grins, it would be interesting to put the bikes on an emissions tester just to see what the machine says the gasses are at.
 
Mike..yes i did ride the 77 750 up to get oil for doing the oil change in the Hondamatic. It was a bit more snappy on the throttle response as compared to before. My thinking is that either a lean OR rich condition has some effects on the throttle responses. Rob says he doesnt need it back right away, so if you or Frank wanna throw it on your bikes I think we can do that.

What if you took it for a test ride at night...would you be able to glance down and see the colour at different throttle openings. If you had the colour tune in #1 or #4.

Brian
 
Probably not because youd have to lean over so far to see down the colortune straight on that youd dump the bike. Now if you hooked up a helmet cam or something on a temp mount you probably could that way. You gotta look pertty much straight down the adapter wire like in the picture to get a good look.
 
Probably not because youd have to lean over so far to see down the colortune straight on that youd dump the bike. Now if you hooked up a helmet cam or something on a temp mount you probably could that way. You gotta look pertty much straight down the adapter wire like in the picture to get a good look.

Or buy an hour at a local MC dyno. :D
 
If you buy the kit new they also give you a periscope type setup that slots over the top to allow you to see the flame colour on hard to get to plugs via a mirror type setup on top, still can't see that working for looking while riding though.

Hampshirehog suggested pulling a plug or two so you could run larger throttle openings without rev'ing the ring out of the bike...
 
Yes - pulling plug leads works quite well to stop the thing revving it's head off. Even then, for WOT you may need to pop it in gear on a stand and apply rear brake (works best if you have a mate help).
 
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