Using a Gunson Colortune to tune a motorcycle carburetor

Unboxing a Gunson Colortune and using it to dial in the pilot circuits on my XS1100
If you buy it here, I get a little kickback amzn.to/2OUDfgD

[@marko1314]

I've owned one of these tools for over 35 years - l bought it to set the Twin SU carbs on my MK3 Triumph Spitfire when l was a young bloke - Those were the days too when car were easy to work on - Flip the bonnet forward (complete with the front wings) Sit on a front wheel and get to any part you want - Anyway still got my old tuning kit including Feeler Guages, Dwell Angle Meter, Strobe Light and Colortune - Happy days!

[@MrMonty414]

Great video. No stupid music, graphics or someone trying to be funny. Colortune and Digisync would have to be the best things you could own for tuning a multi carburettor bike.👍

[@1cisqo]

Andy.... You are a SAINT!!! I have a 98' Valkyrie and have spent countless hours trying to adjust the idle mixture, after a rebuild. I saw you use it on another video then did some research then found this one. It's just what I've been looking for. Thanks so much

[@ANDY5]

I find it works for me. I’ve had some people tell me that they don’t like them so I guess it’s a subjective thing. I hope it helps you out mate, good luck.

[@490SavedOne]

Thanks for the great video! Picked one up with adapters for my son and I to use and can't wait to try it on my '80 XS1100SG rebuild!!

[@gordonturke4171]

Great,thanks Andy,I,ve just bought one of these to use on my xs1100,cheers gordon

[@firestorm755]

Hiya, I've got one of these in the back of the garage. I used it on bikes I've had and cars. But I learnt a lesson. I used it on my Firestorm years ago and it worked. The plugs on the storm are a long way down into the head. Down a tunnel actually and they are tiny plugs. You use an adaptor to get the colour tune to fit. All went to plan untill I unscrewed it....it left the adaptor behind screwed into the head. I nearly crapped myself! It took a lot of fiddling to get out because you screw the main body in with the adaptor on already. I prob won't use it again!!!

[@readingrocks500]

I like the wide band setup , you can really tune in the pilot and the main accurately never looked back

[@pleasantstrummer]

Excellent. Many thanks for producing this, much appreciated.

[@Incrediblemagpie]

Classic, "Here ya have a....Handbook?..." tosses off to the side.

[@jasongray5060]

Subscribed! I never even heard of this. Just ordered to help my carb handicap! Thx!

[@christopherkimmer8240]

I'm feeling the word carb handicap

[@anenglishmaninbrazil3212]

OMG i had one of those back in the day..last thing i used it on was a 2 litre Cortina and it worked pretty damn well

[@9999chippy]

Same here, about 1973 on and old Morris Marina

[@brianevans1946]

Really love the intro music..

[@wobu5361]

Get your flame a nice Bunston blue with Gunston Colortune! Seriously tho, nice vid mate!

[@montwolfman]

Great info Andy. Thanks for posting. BTW, I picked the '81 up today. Gonna start on the carby's tomorrow.and see what gives.

[@ANDY5]

I will be keen to see your progress mate, thanks for the comment. Andy

[@marcconyard5024]

I used this on two of my R series BMWs to good effect. One thing I did find is that it can show up other problems with your carbs which in my case was worn slides.

[@marcconyard5024]

I should've added that I still have my Colour tune. Bought it way back in the early 90s and it still works fine. Never tried it on a fuel injected engine as all sorts of other factors come into play.

[@Carlitos-gc9wn]

Gracias por compartirlo, y en especial, GRACIAS por los subtítulos en castellano.

[@quadflopper1012]

the colortune is great if all you need to do is set your mixture at idle but i found out it won't do you much good if you are chasing a mixture problem beyond that, the actual mixture changes under a load and if you are trying to chase a mixture problem like i am, between 3k and 4k rpms, it's impossible to watch the color burn and ride at the same time, i tried......

[@aaronkeith7336]

Holy FUCK! After watching one video, then you saying this one is in the corner, I’m definitely subscribing. Thank You. 🤙🏻

[@sandmanbub]

Thanks Andy, ordered a 14mm kit and 2 adaptors. Looking forward to tackling a few cycles with it.

[@ANDY5]

G'day John, you won't be sorry mate. Thanks for tuning in, Andy

[@polishguy9272]

Nice vid. Would it be handy for classic two stroke engine carb?

[@marklast2900]

Hi I've got a 1982kz1000ltd what would be the best diy sync tool thanks good videos

[@OldBiker]

I found going from leaded to unleaded ethanol the colour tune gives incorrect readings, I tried it on a couple of bikes and after I got them the nice blue colour, the bikes just stumbled or misfired

[@rcrazee5077]

The tool is an excellent visual representation of what is actually happening inside the combustion chamber. I have a Gunson and been using it for 6 years now, although I normally do not do the inappropriate dismantling of the carburetor when my motorcycle is running well without hesitation and or slow pick up. It is a very good utility for finding leaks and or if the intake system do have leaks that as u turn the air/fuel mix screw and there is no huge variation of the color means the intake system do have leaks. Very useful too on visualization of the needle and jet transition from close throttle to 3/4th opening. Once the right color is set, since the motor is under load during test. after re attaching the original spark plug. A/F mixture must be turned 1/16th to the rich side..max of 1/8th turn. That will be the correct setup assuming there is no leak on the intake manifold.. Works wonder for my motorcycle..I do not have to guess nor to pull over for plug read anymore ever since..:)

[@myshitonyoutube]

Sounds good but a bunch of people say it's very different to rev the engine when it's not under load to when it is therefore it won't work. The motor is only under load when you ride the bike. I guess you have read the plugs after using Colortune so it does work for you.

[@rcrazee5077]

@@myshitonyoutube there is a trick..When doing this on a static mode. simply apply the rear brake or adjust it then rev the engine midway. It always my way. O f course this is one time use only when overhauling your carburetor to clean it. after that, there is no means of tweaking it again.

[@myshitonyoutube]

@@rcrazee5077 I have cleaned my cv carbs. New jets and pod filter which is a pita I've heard. I thought this tool could help me but too many says it's different when the engine is under load. Cool trick you have, thanks for sharing. Do you know why it's different under load compared to reving the engine in neutral?

[@rcrazee5077]

@@myshitonyoutube maybe because of pressure i guess. Carb type motorcycles tend to rely to much on atmospheric pressure. What I know is when the air is dense the better the motorcycle will run in comparison with less dense on the same carb settings. try this when using colortune. put something like a small fan pointing towards the front of the motorcycle. to act as your moving air ,adjust the brake to keep the rear wheel and fool it as if it has load. then adjust the mixture color, when you get the bluish one on idle, we all know depending on the jets used. it will turn to orange, sign of more gas being sucked. If that happens you know how the transition of your jets is reacting. If I am the owner of that kind of transition of course i'll go step lower of the settings during idle and adjust it to near white (leaner side IDLE) then i'll have an optimum throttle midway. There is just too many factors. relying too much on colortune is sometimes messy, BUT when you got it via the VISUAL WINDOW of what was happening inside the combustion. You'll never go wrong with it, instead of just hearing the engine rpm goes up and or down as you adjust the mixture. EYE is far better than EARS for me.

[@myshitonyoutube]

RCrazeE thanks. I'll read the plugs too but I think this tool will make it easier.

[@user-dw3mn3rn7e]

Please help me, i have two motorcycle. The first has 10mm spark plug and the other has 12mm spark plug. What colortune can i use and what adaptor. Thanks a lot. Greetings from Greece.

[@barry9838]

I've had good results using it on my older cars. Engines run smoother, the plugs colour are light brown . I'd like to tune my Yamaha FZR1000 but I have to buy the adaptor because of the smaller plug size NGK DR8ESL. Unlike your XS11 and Duc 900ss, the FZR plugs are deep inside the head, so might be a bit challenging.

[@ANDY5]

Hi Barry, I was thinking about that myself, until recently I owned a 2005 955i Triumph Daytona triple, and it had the plugs buried deep. That is what the scope is for apparently. BTW they do sell a range to fit most plug sizes, thanks for the comments mate. Andy.

[@barry9838]

Yes, the scope helps in deep recess cyl head. Andy, sorry to digress, hope you can do more video on the Ducati ss. Love that too :-)

[@ANDY5]

Digress all you like mate. I will be doing some work on the Ducati soon, I should have started already but other things keep getting in the way. I will be changing the valve stem seals, re-shimming the valves, and fitting new timing belts. Cheers, Andy

[@rosstisbury1626]

cheers mate

[@tomknox8227]

Nice!

[@LeeKirkman88]

pretty cool

[@mcjjordan]

Is this only used for idle?

[@Mathewmartialart]

How did you adjust it?

[@tcherf]

good morning Andy, thank you for great video, do you think that I can use this colortune for rejeting carbs? I think it's possible to do with this tool. I have lean carbs after installing pod filters, when i put bigger jets into carbs I could probably check the mixture with new jets with this tool, is that possible, or it's designed only for idle?

[@roythearcher]

it's designed mainly for idle mixture as its not designed to be run for too long as the glass will crack when the body heats up and expands and the glass won't! besides your engine when running will be under very different conditions when running at anything other than idle and this device is only realy designed to be used to check idle fuel mixture.

[@tcherf]

I wasn't thinking about that this way, you are right, thank you.

[@craigadam6964]

Say Andy, great video, I would like to ask you about the kit you bought. You're kit Pt# is G-4074 14mm. I have a 1979 gs1000l suzuki and the plugs are long. So my question is should I buy the G-4055 14mm that has a deep adapter? Thanks for your help

[@ANDY5]

I have used my kit on a GS1000 with no issue.

[@aussieshaunindk]

Hi Andy do you think you could see the color when the plugs are buried deep in a water cooled engine. Thanks mate, know its an old vid but thought i'd ask anyway. cheers from Denmark.

[@ANDY5]

G’day mate, yes. That’s what the periscope is for.

[@qwaszxpolkmncvb]

Blue is lean, White is Stoichiometric and Yellow is ritch. Those are great for tuning carb circuits. You've got to know what ratios you want during various demands and RPMs. Leaning a motorcycle out does some nasty damage.

[@ANDY5]

+qwaszxpolkmncvb g'day mate. The only way to measure stoich is with a O2 meter in the exhaust. As is the case with all internal combustion engines you generally tune for the peak power band and there is compromise either side of that. The changes made here will have a diminishing affect on the air/fuel ratio as a whole as the rpm increases and you become more reliant on the jet sizes and needle position. Thanks for tuning in, Andy

[@deafdeadfishfloating]

My concern regarding the interpretation is the nature of the plug gap (and spark location) may not be the same... and THAT TOO influences the mixture ignition markedly IMHO, particularly on bikes without electronic ignition. The precise nature of the gap influences the amperage (under compression) for example, and it's a proper 'balance' of that current release (at that point) that determines proper ignition. So... yes, the system is set for THAT test plug, but not necessarily for the plug(s) that are installed is my worry.

[@myshitonyoutube]

..and the engine is not under load. It'll be different when you ride it.

[@waynedl99]

I have 1, great bit of kit. Only thing - there's no t in Gunson ;)

[@ANDY5]

+Wayne Large how did I miss that? Thanks mate 👍

[@waynedl99]

it'll help anyone searching. great vid, not too much waffle like some 😂

[@ANDY5]

Thanks Wayne, and thanks for watching, Andy

[@roythearcher]

There's no 'T' in Bunsen either!!! Jus' sayin'

[@officialmysteriousrider6327]

Andy's motorcycle Obsessions i got this one myself never used it yet gunner use once my bike is put back together. in mine ive got a little glass bottle what is in it ? ? ?

[@ANDY5]

Glass bottle? Not sure mate.

[@officialmysteriousrider6327]

@@ANDY5 wonder if its too clean the glass buddy mine is from gunsons color tune tho just realized yours is aswell it must be a old one mine its a color tune 500 & its got picture's of old weber carburetors so defiantly old type one mate

[@davidnowell1701]

i notice that you seem to be using the pilot fuel screw to adjust the Gunson colour. Is this an alternative to using the pilot air screw? is it an either/or/both or the adjustment must be made with the fuel screw.

[@ANDY5]

Depending on what carburetor design your bike has. The Mikuni carburetors on this bike have a fuel adjustment screw, some carburetors adjust the air. If the screw is located on the air cleaner side of the carb it is an air adjustment and if it’s on the engine side it is a fuel adjustment. Either way it’s adjusting the air/fuel mixture for the idle circuit.

[@davidnowell1701]

@@ANDY5 thank you. I have a GS1000 which has Mikuni VM carbs. These have both fuel and air pilot screws This is where the confusion lies. Regards David

[@robbymagen2]

HI! Andy Like your Videos and wanted to know if you are in Sydney will you be able to give me a hand with the rebuild of my Kawasaki Z 1000 ST i'm stuck with the electrical Harness thank you, regards Robert

[@ANDY5]

Sorry mate, I'm in Hobart

[@Scoottoots]

Wow, that's the first I've seen of this. Do you feel it is a better method than tuning the pilot circuit with a vacuum gauge?

[@ANDY5]

+BlastsFromTheSaddle g'day mate. You don't tune the pilot circuit with a vacuum gauge, that is for carburetor synchronization. If you have multiple carbs you still need to do that too. Have a look here kzbin.info/www/bejne/i5a5iYV-fZV6ars

[@Scoottoots]

Thanks for the lead to the video. Appreciated. I may be a tad confused and perhaps I misspoke. I should have said, tuning the idle circuit with a vacuum gauge. A vacuum gauge can be used to set the idle circuit mixture just same as using a tach, but going for max vacuum rather than max rpm. Well, at least that's always been my understanding. So, is the Colortune enabling you to do more than just set the best idle circuit mixture, being that your only adjustment points are the idle circuit mixture screws? Put another way, is the Colortune device superior to using a tach to set the idle circuit screws? Thanks for you help, as I have some twin carbs on a 1984 GR650 to work on.

[@ANDY5]

+BlastsFromTheSaddle sorry for the confusion. For me the colortune works best because I can physically see the flame and adjust richer or leaner regardless of external conditions such as air leaks etc

[@Scoottoots]

Ah, the confusion was mine. I understand it better now. Thanks so much. Recently subscribed and really enjoy your videos. Cheers :-)

[@edspengeman3407]

BlastsFromTheSaddle was

[@anthonyskorner4511]

Will this tool handle tuning in the the whole rpm range?

[@ANDY5]

Not recommended mate. It’s not designed for that purpose.

[@llewvirtue861]

No

[@callumbalodis1760]

Hey do you colourtune all the plugs or just the one?

[@303storm]

obviously all

[@dozynwk234]

Your camera and its microphone were too close (necessarily so to see the plug window) to the high tension lead and the electromagnetic interference from the high speed switching of the ignition system was overwhelming the audio signal.

[@nikolaos12a]

It works on 2stroke engine?

[@ANDY5]

Not sure mate, I can’t see why not, but I honestly don’t know.

[@jiankhan]

@@ANDY5 It works with any motor that are not Diesel. Back in the days i used it to tune my Mito EV and Aprillia 250 RS, as well as my gxer's 11.