Carb Balance of the T-140V

[ZILCH]

I built a carb balance tool as posted and tried it. I hooked into the vacuum side of the intake by connecting it to the carb balance nipples on the intake manifolds. There are no provisions on the MK1's for a test port without modification that I can tell.

With the tubes hooked directly to the balance hose nipple there was too much pulsing to get stable reading. In addition the oil in the tube ended up getting sucked up by one of the cylinders.

I decided to rebuild the balance rig using the two bottles with a tube to transfer the liquid between the bottles. The tubes from the manifolds of each carb are put in the top of each bottle that leaves space between the tube and the liquid. I believe it gives a buffer zone to smooth out the pulse effect. I also added valves to each line to shut off the vacuum flow during the starting process. I hope that by using the valves as restrictors they will decrease the pulsing effect.

I will try this new set up this weekend and see how it works.

Has anyone used a carb tool on the 650/750 twins or am I just chasing my tail? Should I just do the mechanical syncing and forget about the carb syncing via a vacuum type tool on the 750?

 

[Sea Dog]

Hi Zilch,

Good idea to put a restrictor (valve) in each line for starting and reducing the pulsing. Using a manometer is a very accurate way to get your carbs balanced at idle and just off idle where the throttle cables start lifting the throttle slides in the case of Amals. I have had great success using this method tuning the Bings on my TSS. The engine idles reliably and is very smooth.

I use coloured water in my manometer....less messy.

SD

 

[devo]

Hi Zilch,



I use coloured water in my manometer....less messy.

SD

certainly less messy, but a oil is safer if sucked in to the carbs.

 

[CarlS]

certainly less messy, but a oil is safer if sucked in to the carbs.

That is exactly why I use ATF in my manometer.

 

[DaveM]

Zilch sound like you have a great setup going on here let us know how it turns out

 

[Sea Dog]

Zilch sound like you have a great setup going on here let us know how it turns out

Zilch,

Have you any photos of your manometer. It sounds interesting.

SD

 

[ZILCH]

Here are the pics. I got the basic design off the net when I owned my previous bike. I used under the sink water shut off valves and plumbing supplies. I post how it works when I try the set up after Thanksgiving. The set up is crude but it should work. I sealed the top after inserting the tubes into the bottles with rtv. I bought two bottles from Walmart for 2.22 apiece. It is octane booster. I dumped one bottle into the family van and split the contents between the two. That way if an imbalance pulls all the fluid out of one bottle into the other it won't reach the vacuum tube at the top and get sucked in by the engine.

 

[CarlS]

A very nice job. Much more refined than my crude one.

 

[Sea Dog]

Thanks for the photos and ideas Zilch. Great fun tinkering around with this sort of stuff and a lot cheaper than buying vacuum gauges.

 

[DaveM]

Wow that sure is a cool setup well done

 

[grandpaul]

Personally, I like good quality vacuum guages.

That said, I can usually get a good sync with careful static / cable / slide setup, then simply "listening" to each carb carefully. Typically very near spot-on when I do final checking with guages.

 

[The Seeker]

I wonder how / where I would attach those tubes (if I made a set-up like that) to a set of Mikuni carbs?