My Manometer

Decent? Also, what is a fish tank valve and do I need them. Also, do you think I am ok with fluid volume?

Bring all info and constructive criticism.

Thanks
Jon

Are you using restrictors in those lines?

If not, your engine will likely get a big gulp of your red fluid.

Most guage manometers use a little valve or damper to dampen the pulses associated with the cylinders firing. Envision a sensitive vacuum guage attached via hose to the carb holder vacuum nipple. Now picture that each time that cylinder enters the intake phase and draws vacuum on the carb and guage the needle would jump from 0 to whatever the vacuum reading should be, but then the needle returns to 0 when the intake valve closes. As a result, the needle on the guage appears to be bouncing all over the place as the engine runs. The little damper valve sits between the vacuum hose and the guage. It tends to slow down the change in vacuum at the guage so the needle doesn't bounce. The valve itself has a thumbscrew so it can easily be adjusted to eliminate bounce without totally blocking the vacuum from the guage. I don't know if the liquid/tube type manometers use the same valve, but they might. Ed

I believe the valve is used to close off the manometer before the engine is started. Then once the engine is running you open the valve on both vacuum lines slowly trying to make sure that the fluid doesn't get sucked into the carbs. If the carbs are far enough out of balance this will occur anyways so be ready to shut off the valves.

My suggestion (as I considered doing this myself) is to get two dial vacuum gauges from Harbor Freight or somewhere similar. They are accurate enough and just require a homemade dampener (or pinch the vacuum lines, but that's just a pain in the butt).

Here are the gauges - www.harborfreight.com/fuel-pump-and-vacuum-tester-93547.html - less than $30 for a pair.

These wok great and are very sensitive to any change in vacuum.
Now it is hard to see if at the bottom of your set up, are those T'd together? You have 4 lines, how are you going to use 4 at the same time? 2 should be together pulling the fluid at each end of 1 hose. Or do you have some restrictor in the lines somewhere?

At idle, an average KZ1000 motor will pull around 7" of Hg. That's equal to almost 100" of water. The rest is self explanatory....

Not to bash...
but I've tried the dial guages, and they are a serious PITA.
Not to mention were trying to get the vacuum matched across all cylinders within 2 cmHg. That is just impossible to do with dial guages.
They're not even that accurate from the factory!

A homemade manometer works very good with some homemade restrictors.
Or a Morgan Crabtune, which is the superior unit to all I've tried so far.

Whatever way you go, accurate balance is key to an optimally tuned engine.

GL.

What kind of fluid are you using? I'm assuming you would want something with a a density approaching mercury?

TeK9iNe wrote:
"Not to bash...
but I've tried the dial guages, and they are a serious PITA.
Not to mention were trying to get the vacuum matched across all cylinders within 2 cmHg. That is just impossible to do with dial guages. They're not even that accurate from the factory!"

This depends on the quality of the guages. I have one set of 4 that I believe use astrology to predict the vacuum :laugh: But I have another set of 4 high quality guages that an engineering friend gave me that work really well. I'm sure the Carbtune also works well and probably would have bought one replace the cheapo guages if I hadn't been given a quality set. Ed

650ed wrote:

TeK9iNe wrote:
"Not to bash...
but I've tried the dial guages, and they are a serious PITA.
Not to mention were trying to get the vacuum matched across all cylinders within 2 cmHg. That is just impossible to do with dial guages. They're not even that accurate from the factory!"

This depends on the quality of the guages. I have one set of 4 that I believe use astrology to predict the vacuum :laugh: But I have another set of 4 high quality guages that an engineering friend gave me that work really well. I'm sure the Carbtune also works well and probably would have bought one replace the cheapo guages if I hadn't been given a quality set. Ed

I said Morgan Crabtune... :laugh: Whats this Carbtune thing you speak of... :laugh: :laugh: :laugh:

You're right though, I have seen some nice EXPENSIVE guage sets... the cheapo ones just don't cut it.

I actually caught a factory race team using the Morgan II Unit

Ok, I had followed a model which I found online and as it turns out, not everything on the internet is accurate. Go figure. So, instead of connecting all 4 tubes, I essentially bent two separate tubes, one for carbs 1 and 2, and the other for carbs 3 and 4 and put them on the board. It worked great, or at least according to my readings (which were also done exclusively online). It was a trick to tighten the securing nuts without throwing the synch out of line due to their sensitivity. Other than that, I really have no idea the amount of vacuum that my bike is pulling or is supposed to pull, or how to translate inches of Hg into inches of ATF. At this point I am really only confident that all carbs are pulling equal vacuum. Also, after tuning and a quick joy ride I decided to do the header touch test. All headers were screaming hot, except for #3. It was far to hot to hold your hand on but not as hot as the others. Any ideas regardings causes for this? Carbs were just rebuilt, all carb holders and boots replaced along with air filter. I did the carb float wet test and all levels are equal, plugs are new. Bike runs perfectly in all other respects. The only thing I can think of is pilot mixture screws. I have them set at standard 2 turns out. If the pilot screw for carb #3 is not rich enough, could that cause cooler combustion?

I would appreciate any help.
Thanks

Jon