Vacuum gauge for TBS

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HaulinAshe

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Somebody (I know who) accidentally whacked my Motion Pro mercury gauge. Fortunately right AFTER I finished the TBS on the 07. Now in need of a new gauge and guess I'm ready to invest in something better and without mercury.

What do you recommend?

Purchase from whom?

 
Somebody (I know who) accidentally whacked my Motion Pro mercury gauge. Fortunately right AFTER I finished the TBS on the 07. Now in need of a new gauge and guess I'm ready to invest in something better and without mercury.
What do you recommend?

Purchase from whom?
Try Morgan Carbtune, directly from the manufacturer.

Cheers...

 
Well, I think the Morgan still has the mecury you mentioned doing without. I was checking a few out not too long ago as I need to do the TBS on my bike. I was hoping for one of the digital versions, but they are quite a bit more in price. Check out this link.......
https://www.kowatools.com/cgi-bin/miva?Merc...ory_Code=VACUUM

Bryan

Morgan Carbtune does not have mercury -- it uses solid rods.

from the website:



The mercury free Carbtune II is used vertically like a mercury manometer and works in a similar way - except you have a column of stainless steel rising and falling. No chance of that leaking!
 

The ground and polished stainless steel columns float smoothly through guides that have been machined to fit them. The guide acts like a seal and the column moves through it vertically. This is contained inside a clear plastic tube which gets connected to the engine. The vacuum from the engine draws the stainless steel column up through the guide.
 

As with the mercury manometer the stronger the vacuum, the higher the column rises.
 

Simple!


 

Just like the mercury manometer except it's smaller, there are no liquids to spill and as the Carbtune II is made from high impact plastics and metal it is much more robust.
 

 
How 'bout one of these?

4630_1sa.jpg

 
Thanks for the clarification Rick. I missed that aspect when I was checking into it. I know the photo sure looks like the liquid. I am still thinking it all over. I like digital toys, so still leaning towards that thing. Will have to see how things play out here in the next month or so.

Thanks again, good info.

Bryan

 
I know you aren't lookin for cheap, but why wouldn't a single vacuum guage with 1 to 4 manifold work well? Calibration wouldn't even be necessary. If my mercury ever spills/breaks I'll give it a try. The manifold could be got for cheap anywhere they sell aquarium stuff.

 
I m in the measuring instrument business, i was looking to buy one for myself.

What is the measuring range in inches of mercury do we need ?

 
I m in the measuring instrument business, i was looking to buy one for myself.
What is the measuring range in inches of mercury do we need ?

Trusting my imperfect memory here: Actual values while doing the sync are pretty low....in the 2 to 3 inches of mercury range...maybe up around 6 inches at 4000 doing part load sync. But, you want enough range to rev the engine and lift off the throttle without topping out the guage so you would need something in the max range of 14 to 16 inches of mercury I would think to be safe. Those numbers are at least in the ballpark.

 
I know you aren't lookin for cheap, but why wouldn't a single vacuum guage with 1 to 4 manifold work well? Calibration wouldn't even be necessary. If my mercury ever spills/breaks I'll give it a try. The manifold could be got for cheap anywhere they sell aquarium stuff.

Theoreticall possible with a manifold and four valves so as to open only one spigot at a time to the gauge.....but.....pretty hard to do a sync that way. Since you are looking for trends in the movement of the mercury columns as much as the absolute value at any given instance a fixed gauge reading when switching from one port/cylinder to the next would be pretty imprecise. Better than nothing maybe but not by much IMO. This is especially true if you are trying to do off idle and part load sync of the throttle linkage at 4000 RPM. Most of the time the mercury is moving so all you can go by is the relative position of the mercury columns.

I have personally used one of the digital type meters and different setups with gauges and it is very hard to beat the old carb-stix type mercury manometers. Other than the fragility of the mercury tubes if you drop them they work well, are very well damped and provide excellent side-by-side "data readout" that is very hard to achieve with the digital or guage systems. The Motion Pro system with the sliding rods might work well but the motion range seems relatively low compared to the mercury tubes. I still have my same old mercury tube carb-stix circa 1970 that work fine today. No need for adjustment, calibration or anything else. I finally had to replace the rubber tubing after all these years but otherwise they are an excellent tool. Not sure why there is some aversion to the mercury style sync tools. It is not like you are going to accidentaly drink the mercury or anything.

 
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I have personally used one of the digital type meters and different setups with gauges and it is very hard to beat the old carb-stix type mercury manometers. Other than the fragility of the mercury tubes if you drop them they work well, are very well damped and provide excellent side-by-side "data readout" that is very hard to achieve with the digital or guage systems. The Motion Pro system with the sliding rods might work well but the motion range seems relatively low compared to the mercury tubes. I still have my same old mercury tube carb-stix circa 1970 that work fine today. No need for adjustment, calibration or anything else. I finally had to replace the rubber tubing after all these years but otherwise they are an excellent tool. Not sure why there is some aversion to the mercury style sync tools. It is not like you are going to accidentaly drink the mercury or anything.

While changing the tubes last year on my 1970's carb stix, I broke a glass tube. So, I

replaced them with the same thing. Simple, and effective (K.I.S.S.).

 
Thanks everyone for the suggestions.

My dog lives in the garage (most of the time) and my children have never enjoyed my childhood experiences of playing with mercury. So there is both reason for health concerns and reason for some of my odd behavior. It really hit home with me as I was trying to clean up all those silver dots splattered across the garage floor. Not to mention how badly it ruined those house shoes you all have come to love!

I'm going with the electronic from Sport Bike.

 
Somebody (I know who) accidentally whacked my Motion Pro mercury gauge. Fortunately right AFTER I finished the TBS on the 07. Now in need of a new gauge and guess I'm ready to invest in something better and without mercury.
What do you recommend?

Purchase from whom?

Was your 07' off by very much?

If you fixed it did it help much?

 
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