Colortune

[ACE]

Hello folks,
I got a colortune from Ebay. It is brand new. The problem I ran into is i can only get a blue color no matter how far i turn the mixture screw in or out .
First i screwed it in and counted how many turns it was set at. P.S. they are all set at 2 and one half turns.
When i let the bike warm up i popped the colortune in and found it makes a differance how it runs when i adjust it but can't get the color to change, it stays blue.
I can say the carbs came off the same year bike and since i put the air box back on it runs well. but i don't know what kind of shape there in, could be dirty inside?
I can also say i just got a new pair of glasses 9 months ago!
Still at 46 the eyes start to go! Right Boys?
Anyone have a similar problem? I mean about the colortune!
ACE

[Bill]

Re: Colortune

Ace wrote:

I got a colortune from Ebay. It is brand new. The problem I ran into is i can only get a blue color no matter how far i turn the mixture screw in or out.

On a set of clean carbs with clean unbroken pilot screws, the color should change. Did this happen with all four pilot screws? One common problem is broken pilot screw tips, caused by an overzealous, ham-fisted "mechanic". It would be unusual if all the pilot screws were broken and/or the holes were blocked, but not unheard of. In any case, to eliminate any doubt, I'd

• Pull the carbs
• Remove and inspect the pilot screws
• Look down the pilot screw holes... you should see daylight coming through the carb throat (use a flashlight if needed)

If you find that some are blocked, see the tech tip by Ken Talbot and Yours Truly:

Idle Mixture Screw - Broken Tip Removal

I can also say i just got a new pair of glasses 9 months ago! Still at 46 the eyes start to go! Right Boys?

Started at 40, but ten years on I can still pass my triver's (and pilots) test without 'em!

Good luck and keep us posted on your progress!

[nashville_bill]

I too bought a Colortune but I have a different problem. Mine has an arc from the center electrode to the case which, of course, kills the cylinder and makes it useless. I have cleaned the insulator several times but it still arcs.

I hope you get over the blues.

[Dennyz]

Check float bowl levels

[auxtian]

Is there a difference between a colortune for a car and a bike???
and one thing I was wondering about was the temp setting on the plug?? Surely you would need the right one for different motors (hot plugs and cold plugs) they burn different.
So what is a colortune...hot or cold??

[ACE]

I could only find one kind. Need adapters for different plug sizes.
Good question but I have no real awnser.
ACE

[skids]

Colortune is for checking combustion at normal operating temp. You have to warm up the bike first because it will begin to be very lean and then get richer as it warms. Use a box fan to cool the engine. Also, if you suspect other problems like a cracked exhaust collector (under the heat shields of the foot pegs), you may as well get that fixed because there is no carb adjustment that can fix that IMHO. I have seen the problem that you state with bad baffles in the mufflers and also with Harley mufflers when the transition piece is too short.

[auxtian]

The poor old girl is using a bit more fuel than usual about 150Kms to a tank and is running a bit rough, (maybe my bones are just noticing it more) plugs are a bit white which is not what I would expect if it is rich. Carbs are balanced ok, pipes have not changed, so the last step I guess is check valve clearances.
I will pick up a colortune today and try that first.

[chopper]

Originally posted by auxtian
plugs are a bit white which is not what I would expect if it is
rich.

hi,your quite right white plug = lean running = heat.sounds like a vacum leak?

[auxtian]

Might block the vac tubes at the inlets and see what happens but the higher fuel consumption is a puzzle if it is running lean, and not so smooth but still jumps along OK??

[auxtian]

Got my colortune and found the burning to be blue BUT No.2 cylinder is firing constantly but igniting intermittently .......Hmmmm......I can feel a weekend without a ride coming on....must get those carbs apart I think.
Anyone tried different carbies with any luck???