Throttle body balance (V7 Classic-twin throttle bodies)

[jackson]

For many years, I balanced my carbs & throttle bodies (primarily on BMW's) with a balance meter that I bought in the early 80's.  I sold the meter when I quit riding for several years but now that I'm back in the saddle for the last year, I bought a Morgan carbtune several months ago.  Yesterday, I decided to try it out on my 2010 V7 Classic but I'm having some difficulties.
1.  I hooked the tubes to the vacuum port on each throttle body and the mercury on the left side reads much higher than the right.
2.  When I turn the air-bleed screws on each side, there is no appreciable difference in the mercury level for either side.
3.  I reversed the L&R tubes to the vacuum ports but still got the same imbalance & no changes in the mercury level other than the R&L are now reversed.
4. The readings are pretty much the same whether the bike is at idle or the engine is running at 2-3-4-5k rpm's.
5. I've also checked the free play in both throttle cables and nothing changes (other than the rpm's increasing) when I take too much free play out of one of the cables.  The mercury level stays the same.

What am I missing?  Comments & suggestions please.
Thanks

[Vasco DG]

Have you read the manual?

[jackson]

Have you read the manual?

Yep.  Read it three times before attempting to use the new TB balancer.  You have to install a reducer (supplied with the meter) in each tube and that was also done.

[Vasco DG]

Close air bleeds, high speed balance with bell crank screw, kill engine, Reset TPS, set idle speed and idle balance with bleed screws.

[jackson]

Thanks Pete but I had already tried this several times. 
Earlier this morning, I called a friend who has a balance meter and he brought it over to my home; we hooked it up and his meter worked fine on my Guzzi.  So, we hooked my meter up to his bike and it did the same thing that it was doing on my bike.  There's something wrong with my meter so see if it's something I can fix or if Morgan will need to replace it.
By using his meter, I was able to balance the TB's.
Thanks.

[Kiwi_Roy]

I'm and Instrument Technician, have been for a long time.

Would someone please explain to me how a stainless steel rod can indicate pressure?
How is that related to a mercury column?
It's beyond me 

[RinkRat II]

 Greetings, Kiwi,
 I wondered the same thing....Here ya Gohttp://www.carbtune.com/carboprn.html

    Paul B