Cheers mate, very in depth explanation you've done here. Well done.

Ooo send us photos to the support page on our website we’d love to see!

What if you don’t have a rev counter?

@@rayestanley517 id buy a cheap one off amazon or 4into1.. kinda necessary if you really want to dial in your carbs

great idea, especially with how many times I've dropped the cap haha

bench sync all carbs and don't adjust #2, boom! you have a reference carb!

Definitely a bit more work at the beginning of the sync to know where you are going but we actually prefer the early style over here at CMC. Glad the video could help you out! Once you get two in sync you're good to continue as the later style!

we will have to check it out!

I believe a fish tank valve would do the same thing for you Murray!

That's how I use to do the job on my bikes and customers bikes. I have done this method on my Jaguar and many multi carb setups on cars as well. In fact my genuine Jag manual actually shows and describes this method as well as another little bit of info, It recommends a litre of methylated spirits in each petrol tank once a month to remove water from the tank and fuel system and keep it dry. This method works very well and served me well, as well as the tripple and quad gauge sets. Its ironic that Brendan said that not to use the multi gauge sets as I found I had more reliable results with the ear and hose trick than using the combination set. Especially so with my CBX's because I had to borrow a second set of gauges to do the job. I found I could get better sync with the hose on the six's. Makes total sense now trying believing all six or eight gauges would be equal . I now think not . Workshop tool calibration was not a big thing back then but it certainly is now and can be very costly getting them done every year or two to comply with standards and accreditation. My preference is still to use the hose and ear trick or the manometer, but if the customer or friends are looking over my shoulder and they think they know it all , I will use the gauges to please them.

@@ScatManAust Haha yeah definitely. Sounds like your customers should trust you more, CBX's are monsters to tune! We like to teach this one gauge method because it's foolproof and removes a lot of variables and user error. For someone who knows what they're doing though, there's plenty of options like the hose and ear method. Thanks for the info, and does the metholated spirits just go right in with the gas?

@@Common-motor It goes well . Its much like methanol and ethanol, being hydroscopic it will take on the water and being mersible in petrol, will pass through the carburetors and so dry the tank of insoluble water. Obviously it wont work miracles with huge amounts of settled water but used on a regular basis will work as Jaguar state. And when it comes to EFI systems then I cant see any problems there as the ECU will compensate. As far as working with diesel, I have never tried. I certainly would not try it in a common rail system but the old conventional plunger and rotary dpa pumps may work. I still use methylated spirits to this day albeit once a year in most of my vehicles. Actually another great use for it is to clean all the plug leads, boots, coils and distributor caps inside and out . Doing this drastically increases the life of the system due to not jumping and tracing, but the biggest benefit is from not drowning the ignition in the rain or cleaning the engine.

@@ScatManAust ill have to give it a try in my tanks!

Link in the description!

It shouldn't matter, the air to fuel mixture screw will just be your idle air to fuel. I usually do it after because its easier to hear the difference in rpm change with the bike running on perfectly synced carburetors.

Sounds like you need to vacuum sync. Hanging idle is one of the symptoms you will notice without it.

Hey Francisco, that will be it for synching! You will still want to go through and tune your idle air mixture screws and run the bike. Once synced is a good time to run the bike to check the running condition and performance. If you made any changes from stock if everything else is tuned appropriately its a good time to check your jetting.

@@Common-motor thanks so much

Till the gas begins to response faster

Interesting is the right word. You’re far better off with carbtune.

If that’s the only piece you’re needing you can message our support and we can get you just the splitter!

Stay with carbtune. Great video, but why overcomplicate a pretty straight forward sync process with all that extra plumbing and one guage. If you can afford all that setup, you can afford three extra guages instead. Lol Just my opinion

Plus with the rpm changes in between, etc etc Too many variables to have discrepancies. Use a carbtune or similar all 4 at the same time setup, and i have been doing this a while.

It’s going to come down to whether or not the vacuum sync ports are the same thread. Message our support at common-motor.com with what thread your zl900 uses and we can confirm for you

We sell the whole kit on our site ready to go!

CMC claims there too much variation between the gages in the 4 gage setup. Many if not most people will disagree with that.

We’ve had gauge clusters burn us in the past and find this way it’s always foolproof with the least variables is all! At the end of the day though if you get those carbs dialed in beautifully with the gauge setup you’re using then it’s a winner.

@@Common-motor i bought this inexpensive gauges, similar that you got. I checked their precision to each other with one easy method. I bought a cheap hospital injection without a needle, and connected it to each gauge. Then i checked every gauge by itself (I pulled the injection all the way from bottom to top so every time you vaccum the same ammount of a air ). All the gaugea showed almost same result. Another methode to check you gauges is with brake bleeder pump. What do you think about this?

@@tomopope4019 what you did is a good way of checking the gauges. You could also use a 4 way splitter and a brake bleeder pump to calibrate all 4 gauges at same time. At the end you will find out they are pretty close to each other.

Hi there, If you're still interested: to upgrade the CBX650 to 75hp, you'll need to change to a bigger camshaft and change ignition timing.

@@asborgeirssoneiriksson9053 Thank you! I'm in the process of a rebuilt....of a rebuilt. Rebuilt the engine once and after 300km it starte ticking/knok.....

everyone has their method! We find this method an easier and affordable method to teach but as long as you are getting the sync spot on with the method you are most comfortable with that's what is important. Heard great things about mercury gauges! I don't trust myself to not suck mercury into the engine though haha

@@Common-motor it's not my method it's the proper method...raced and worked for Honda for over 25 years... You won't suck mercury into the bike unless you have some crazy idle going on...

10w40 is stock recommended but can go with 20w50 if you ride in a hotter climate. I use Amsoil metric synthetic in my CB550 without any issues but some people fear using synthetic in older engines for whatever reason. A good deal of people use regular Shell Rotella diesel oil. Any motorcycle oil designed for a wet clutch will work. Just personal preference.

@@supersportimpalass im in the Netherlands, not that hot. Thanks for the reply

@@wilfredprins9718 You're welcome. Motul has their 3000 4T 10W40 mineral oil which I believe is available to you. www.motul.com/nl/en/products/3000-4t-10w40--2

No two {inexpensive} vacuum gauges will give the same progressive and total readings. Sure it can be done as you describe, with a separate gauge off each carb. This method is obviously used by many and does, in most cases, give a reasonably satisfactory setting and tune of the carburetors. However, the single vacuum gauge will give the same vacuum readouts for each of the carbs and, therefore, be more accurate. The cost of adding four gauges to a kit for sale, instead of one, will also increase the total cost of the kit, whether purchased as a kit, or made up from individual components by the DIY carb tuner. Personally, for the sake of accuracy, I would use the single vacuum gauge and five or six valve gang of "Aquarium Air Flow Distributors with Controller Valves", using one of the valves for the vacuum release, instead of findling with a plastic cap to remove and replace {and lose}.

We find this to be the easiest and most accurate method to teach and use but there are many ways to do it. The Morgan Carbtune is a great device and can do the job as well.