Carb sync tool?

[Edgee2004]

I'm not trying to be a jerk, or harass you, HM. I guess it is either the German heritage in me, or the aircraft mechanic training. Regardless, I believe there is a correct/approved procedure and every other way. That is not to say that other procedures are wrong. Knowing the proper procedure, or the theory behind it, makes it easier for people to make educated decisions. In this case, I don't think it makes it more complicated to use the correct procedure, and it may yield better results.

I also believe that the value of this forum is increased when the quality of the information posted is improved. Most of the members are new to motorcycles (myself included), many have never had any training or done any mechanical work. The knowledge we pass along may have a lasting effect on the members, long after they have moved on. Maybe I should have been a teacher...

I am a teacher. an avaition teacher. lol

but seriously your are completely right. miss information has a tendancey to continue to compound an issue.

 

[Edgee2004]

I understand that, but I was speaking in the context of an XS400. As to these little bikes, why make the process more complicated than it needs to be?

just a side note my also be the german, irish, english, indian (native), ..... yeah.
anyways nothing about a carb is simple if you do not have a grasp on the principles of operations.
research vinturii's theory.
research carb adjustments conserning air and fuel adjustments.
and research the effects of the jets and needles.

there is a great mukuni carb pdf somewhere on the interweb, and a greatly detailed honda CB750, four bank carb set up, pdf that explains the reasons for syncing.

but lets get it fixed and go ride.

 

[HoughMade]

I can not disagree with knowing the "why" behind the design. I never suggested otherwise.

...but if you know the "why" as to these bikes, you will also know that expensive gauges are not necessary (if you have them, that's great). In fact, knowing the "why" behind carb balancing will let you know that while gauges may go out of calibration, 20 feet of tubing, careful measuring and the laws of physics never will. Use the gauges if you have them- no reason not to. However, don't think that they give a better result on an XS400.

 

[boomer91]

I think this thread has gotten alittle out of hand with opinions and information that doesnt even answer the original question asked. With that being said I appreciate all the advice that all of you have tried to put forward, but in my past experiences being an automotive tech I have found out if you buy good tools from the start you are far better off. So I bought a sync tool with good reviews instead of "making" one and possibly being a complete waste of time and money.


The tool i have requires a calibration before syncing. It has step by step instructions on how to do this and is very straight forward, except for how to find the master carb or tb. This is ALL I need to know at the moment. I dont need your opinions on buying or making tools to sync carbs. The instructions say "non-adjustable master carb or tb" this is why I dont think it is the carb with all the adjustments next to it....but then when I researched more I found that this is completely opposite and that the master carb most of the time has the throttle cable directly attached to it. This is very confusing....I'm thinking that the carb on the kickstart side of my xs400 would be the master carb, since it has tc directly attached to it and the vac tubing from the tank runs to that carb.

Does this sound correct???

 

[Edgee2004]

The master carb is not going to have an adjustment for the butterfly. Up load a photo and I'll tell you. Ant adjustment that will move the butterfly on the "slaved" carb is the adjustment you use to sync. I'll try to look at my bike tomorrow.

 

[Edgee2004]

Also tc and any other linkage or connection will not have a meaning, to me, maybe on this bike it is the tell. Have you had the carbs off or are they off? Look at the from the motor side. And look at the page I linked earlier.

 

[Edgee2004]

Look at this web page. The carb on left, or the #2 carb is the master. This is the carb on your kick starter side. If your carb is anything like this that is.
http://www.thechopperunderground.com/forum/index.php?showtopic=50781

 

[16VGTIDave]

Boomer, sorry for the confusion.

You are correct. The right carb (when seated on bike) is the master carb. The throttle cable and idle speed adjustment are both on this carb. SOHC and DOHC engines are the same in this regard.