Colortune

[LanaTheGreat]

I once had a tool called Colortune. It is a sparkplug with a window, and you set the air/fuel mixture according to the colour of the flame. Blue too lean, yellow too rich. From yellow you turn the air screw to just when it starts burning blue, and your mixture is correct. I have been asking around in our spares shops and they say colortune is off the market. Does anybody know this great tool, and if it really is off the market, is there some type of replacement that does the same job?

[Thom]

Gunsons colourtune, i do believe theyre still available, particularly so on eBay.
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Current Bike: 1996 Yamaha TRX850 (The Japanese-Ducati One).
Previous Bikes: 1990 Honda NSR125 'Rothmans' (The smoking one), 1990 Suzuki GS500e 'Caf? fighter' (The loud one), 1987 Kawasaki GPX400r (The quick one), 1997 XJ600s Diversion (The reliable one), 2000 Kawasaki ER-5 (The spontaneously combustive one)

[tatters]

Halfrauds sell them
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Past:NRG50,AF1125(x2),NSR125RR,ZZR250,CX500,VFR400,KR1S,ZZR600(x2),CB400N,YZF1000(x2),KH125,Z200,FX400R,CBR954RR(x2)GPZ500S,GT550,VFR750F(x2),RD350N,XR650R,CBR600F,CB250,KDX250,YZF750R,CRM250,400EXC,KLR650,TTR600RE,DR350S,R100GSPD,RGV250,VMAX1200,DL650,KZ750 Present:G650XC,C12,CRF450X,1190ADV

[Finglonga]

[garyd]

I still have a complete one
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CRF230 all you need

[tatters]

[LanaTheGreat]

I am from South Africa

[FerretFing]

There is actually a motorbike specific one (low volume) - might get one myself

Did a quick search & found a few places;

https://www.gunson.co.uk/item.aspx?cat=673&item=1852

https://www.carbtune.co.uk/c.com/colortune.html

https://www.frost.co.uk/item_Detail.asp?productID=9518

https://www.topgear-sales.co.uk/products.asp?deptid=10&u=IEGDIDJNLAJHJJKKFLIH

https://www.fast-tools.co.uk/acatalog/Carburettors.html

Ebay is worth a look also of course

[Mr Hammers]

Someone on eBay doing them for a third of the price of most of those others at 9.99.

i had one years ago and it was very good. No idea where it got to, so i've just bought one again, only £13.98 with shipping.

[The Artist]

I just bought one off ebay, looks like a good buy for £13.98 and I will report back with any info.

[ST125SM]

I was initially impressed when I saw these first but during a bright summers day, it was impossible to see the combustion - perhaps the tools have been revised since?

Anyway, thinking about them again after reading this thread, my biggest concern is that while you can (presumably) see the colour of the combustion while stationary, isn't the art of tuning more to do with under load conditions which, for those of us without a dyno, means a moving bike. I can't begin to imagine the problems associated with viewing while riding?


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Regards,
Mike

[LanaTheGreat]

I would guess that trying to look at it on a bright summer's day is not the brightest idea. Do it in your garage with door closed and lights switched off. You won't watch movie from a projector on a bright summer's day either, unless you make the place darker.

I see on ebay that there is a converter type thing that makes the colortune fit on either a car or motorbike engine. Pity the converter is the same price as the colortune itself.

Riding the bike and looking at the combustion is a cool idea

As far as I can recall you do set it while the engine is revving up too, but only for short bursts. I'm saying this under correction, as I used this stuff over ten years ago. Likewise, mine also disappeared and only recently did I think of it. Couldn't remember what it was called until I enquired at a spares shop. Here in South Africa it is apparently off the shelves. They probably never advertised enough, as I think people would drool for a tool like this, especially with the soaring fuel prices.

Do let us know if you did find that one on ebay, as I am considering buying one too.

[Stalk]

[yandy_yay]

[LanaTheGreat]

Yeah that does sound kinda odd. But I guess you understood what I meant

[LanaTheGreat]

[Zimbo]

I can't really see the relevance of the Colourtune product for modern bikes. it'll help you to get the mixture right at tickover, but the air / fuel ratio under load can't be monitored and therefore jet size and needle position can't be monitored either. A dyno run will do a far far better job.

[Mr Hammers]

Being over 17 years old, i'm not sure my NSR counts as modern...but you're right, it can't measure under load - unless someone can figure out a way to monitor it while riding - but it is just reassuring knowing that the idle is, and can be, set correctly.

If it's impossible to get it set right, then it might help to indicate other problems.

That said, if i had something newer and bigger then i'd definitely get it dyno'd, but i'm not sure it's worth the cost for my bike - i'm guessing dyno sessions ain't cheap.

[Ariel Badger]

Thanks for the link, Just bought one from the Ebay chap.
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Bikers make great organ donors, get 115 on your licence today.

[LanaTheGreat]

It seems this Colortune is not only for setting idling mixture. Take a look at this link:

https://www.xs11.com/tips/maintenance/maint34.shtml

There are procedures for:

-- Idle Tuning (for bikes +-900-1000rpm)
-- Off-Idle Tuning (obvious)
-- Low Mid-Range Mixture Check (1800-2500rpm)
-- Mid-Range (3500-4000rpm)

This is all done using the Gunson's Colortune. There you have it, better tool than you bargained for.

This guy at ebay should pay me some royalties, it seems I've been making him some business.

[Mr Hammers]

Nice find! Well, if i hadn't bought one already, i definitely would now.

And i'd suggest that anyone buying one from now on should put "Lana sent me.." in the additional info.

[LanaTheGreat]

Now there is a brilliant idea! Perhaps I could get some discount when I buy mine...

[FerretFing]

What do you think the major differences(if any) would be between this (the car/general version) & the motorbike specific one? Would it be less accurate maybe? Or is it just a way to get bikers to pay more for exactly the same product?

[virus]

bike spark plugs are a different size to car spark plugs.


Cheers
John
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own: 81 xs1100g...
owned: 85 rat CG (sold), 91 GS500e (stolen), 84 gsx400f (scrapped), 81 z250 (siezed, siezed, scrapped), 83 cb250rs (sold), 84 gpz750r ratfighter (killed) 84gpz400 (sold), '80 cb650 ratfighter (wrote off) 95gsx6/12f ratfighter (killed) 91 xj900 (sold)
stinkwheel Well I just had my hands up a pigs fanny. Which makes your concerns pale into insignificance.

[FerretFing]

The motorbike version comes in 10,12 & 14mm kits & mentions "low volume"

https://www.gunson.co.uk/item.aspx?item=1853&cat=673

just wondered if this would really make any difference?