colortne

I recently synchronized my carbs on my 82 XJ 650 and was seriously impressed with the increased performance. I am looking at purchasing a colortune to adjust the mixture, is there any special tools needed to adjust the mixture , and any tips for using the colortune

Dave

 

look through this thread .

colortune discussion

 

My advice regarding TOOLS:

Make yourself a screwdriver that FITS the Slot on the Pilot Mixture Screw with such precision that there is absolutely NO side-to-side play whatsoever. None.

There's too much at stake to have the Screw become ruined by having the "Wings" aside the Slot be able to move to unoccupied space without the body of the Screw being moved along with them.

It's imperative that the Ultra-fine Threads of the Adjustment area within the Pilot Screw Bore be CLEAN.

The best course of action is to add a Non-flammable lubricant to the hole and heat it.
Vegetable Oil is perfect for this.
Heat the Oil and let it lube the threads around the Screw.
Then, sop-up the Oil with Q-tips and Turn the Screw all the way DOWN.
Do a thorough cleaning of the Bore.
Add some light oil. Marvel Mystery Oil is Perfect for this.
With the light oil and the proper fitting tool ... bring the Screw UP "Exercising it" up and down to spread the lube as necessary.

Once you have the Screw extracted ... add a film of NeverSeize to its threads.

On ColorTuning:

With the Pilot Screw at a Pre-set of 2-3/4 Turns OUT from Bottom ... begin the ColorTuning Process of observing the Color of the Burn within the Combustion Chamber.

Adjust the Screw OUT. When the Mixture is BUNSEN BURNER BLUE ... Continue adjusting the Screw OUT until the Mixture is TOO RICH and you see the BLUE change to a color indicating the MIXTURE is Incorrect.

Then, with the Mixture TOO Rich to provide the Tell-tale BLUE needed for OPTIMUM Performance ... Adjust the Screw back IN -- Very, very slowly and precisely until the BLUE ~~> Returns.

THIS ... is the Point where you are adjusted for near-excellence.

The ColorTune Plug has Dialed-you-in to a Pilot Mixture with a highly-accurate Air-Fuel Ratio.

The FINAL Adjustment will be determined by PERFORMANCE alone.

Although the PLUG has insured you that the AIR-FUEL RATIO is adjusted within the parameter for a "Good Burn" ... you will only know if further Micro-Tweaking of the Mixture setting is at THE SWEET SPOT when you ROAD TEST.

Off the line ...

If there is a little "Bog-Out" when the Engine comes OFF-IDLE and Transitions over to MAIN JETS:

The Mixture is still a (auto-censored off-color remark) hair too RICH.

If she "Poppity-popps" for a second, hesitates, and then takes-off great (Not likely - if we ColorTuned on the RICH side) you're a bit LEAN.

You have a 1st Class Tweaker's License!
Tweak that Screw IN or OUT a hair!

 

Hey, my colortune is on its way. If I have that, do I still need to shut off the YICS or can I tune it w/the colortune w/the YICS running?

 

You only need the YICS blanking tool for carb balancing (and many say not even then).

No need to worry about it at all when checking idle mixtures with the colourtune plug.

 

My Colortune is also on it's way (or at least I hope so)...

I just want to say that I saw for first time that toy on this forum. I must have It! Thanks everybody for enlightening me

 

here is a real newbie question...what size should I be ordering?12mm,14mm?? its for a 1982 xj650j maxim........ thanks

 

You need a 14mm.....I believe only the xj550 has the 12mm threads.

-Nick

 

Yep, 12mm for 550, 14mm for 650/750.

 

1992-on XJ600 or Seca II - 10mm.
Just for record in this topic

 

what size is the maxim x threads?? 10mm?

 

the maxim x is 12mm