vacuum

[dragoncutlery]

any one know what kind of vacuum these carbs pull im looking to get some gauges to make a different sinc tool (not happy with the manifold on the bottle tool) but want to make sure that the guages i get will be within range

oh yah if it helps 93 750

[joe]

From what I understand, the specific amount of vacuum each cylinder generates is not necessarily important. What is important is that each cylinder is pulling the same vacuum across the board.

[dragoncutlery]

yah i know i just don't want to buy 4 gauges and have them bottomed out because they don't read high enough to keep up with the kat

i have two choices

http://surpluscenter.com/item.asp?UID=2009050912153295&catname=hydraulic&item=21-1605-CW

or

http://surpluscenter.com/item.asp?UID=2009050912153295&catname=hydraulic&item=2141

both have there own scales so its hard to compare apples to apples

[Kreylyn]

Before you purchase...

Vacuum created on the bike is a pulsating vacuum. Any guage you purchase to use with this must be set up to compensate for the pusating action... otherwise your needles will just jump all over the place and you will not be able to read it.

Vacuum is not much, I believe the 30psi guage would be enough if you can compensate for the pulse.

You do not need 4, only 2 guages are really needed. Sync 3-4, then sync 1-2, then sync 1-3.

Krey

[dragoncutlery]

grrrrrrr forgot about the pulsing and the only lf gauge they have isn't graduated enough for a sinc

[Diggity]

Hey, If you need assistance let me know, I've got a carbtune.

[dragoncutlery]

im rebuilding my sobe test bottle manifold to some thing more "accurate in my mind" than i have seen on others bottle carb sinc tools if im not fealing it when im done then i might have to barrow that carbtune some thing about the shared oil flow doesnt mesh quite right and till the pulsing came up the guages were cheep enought to try out

[Wild-Bill]

If you look carefully at the gauge faces you'll notice that they both measure 0 to -100 kPa/0-30 inHg. They're the same scale. According to my Morgan, I draw anywhere from 12-26 cmHg or .5-1 inHg depending on RPM, etc. Those gauges won't work for you at all. The whole pulsing thing is dealt with by having a restrictor in each of the connection tubes. That turns the rest of the tubes' lengths into a vacuum reservoir. That should work for your Sobe bottle thing, too.