Carb balance - why all the fancy tools?

**Mike.Gayner** · 17th March 2015, 20:01

Carb synchronisation seems to be one of those things that a lot of people leave to the shop because of the apparent need to specialised tools - vacuum gauge or manometer. I balanced the carbs tonight on my GSX in pairs using just a $2 piece of clear tube and some oil.

Shit pictures:
Hooked up - the air bubbles dissipated immediately upon starting the bike

Running - this pair were spot on, didnt need any adjustment

All up the process took about half an hour, and only minor adjustments were necessary. This method is more accurate than a set of Chinese gauges - you can't fool physics.

**tri boy** · 17th March 2015, 21:05

Originally Posted by Mike.Gayner

This method is more accurate than a set of Chinese gauges - you can't fool physics.

Chinese gauges maybe, but not as good/accurate as quality mercury filled manos.
The dampening and smooth flow of the mercury is the winner.
Mine are 30yrs old and work as if they were bought last week.
The long tubes, (1mtr) also are an advantage over the more compact design.

But yes, simple oil damped ones beat gauges every time.

**nzspokes** · 17th March 2015, 21:57

Ive got a Carbtune. Easy and fast.

**Drew** · 17th March 2015, 22:00

Piece of rubber hose, one end held at a fixed point on the bellmouth, the other held to your ear. When they sound the same, the throttle is set.

**roogazza** · 27th March 2015, 11:18

Originally Posted by Drew

Piece of rubber hose, one end held at a fixed point on the bellmouth, the other held to your ear. When they sound the same, the throttle is set.

Old school bud !
I was doing that stuff with Jaguars in the sixties,had some great teachers.
Twin SUs and Triples on the "E" Types.
There were vacuum type gadgets with floating bubble thingys but I went the "Hose" method.

**Drew** · 27th March 2015, 22:01

Originally Posted by roogazza

Old school bud !
I was doing that stuff with Jaguars in the sixties,had some great teachers.
Twin SUs and Triples on the "E" Types.
There were vacuum type gadgets with floating bubble thingys but I went the "Hose" method.

Same as eyeballing a straight edge. The accuracy is remarkable.

It is the only way to properly balance a six pack Charger I'm told...and even then it has to be done with the engine loaded. So if ya don't got a dyno, you take the bonnet off and sit on the guard while the car is being driven.

**ducatilover** · 28th March 2015, 12:31

I built a manometer for doing awkward carbs, otherwise the tube is fastest and accurate.
Fuck vacuum gauges.

**ruaphu** · 29th March 2015, 07:42

Another vote for the carbtune gear. Brilliant tool, easy to use, cheap enough, and accurate as.

Sent from my iPhone using Tapatalk

**Drew** · 29th March 2015, 10:50

Originally Posted by ruaphu

Another vote for the carbtune gear. Brilliant tool, easy to use, cheap enough, and accurate as.

Sent from my iPhone using Tapatalk

This thread has been taken over, we don't care about your fancy tools.

**tri boy** · 29th March 2015, 11:45

Originally Posted by Drew

This thread has been taken over, we don't care about your fancy tools.

"I have accute hearing"

"I don't care about your jewelry old man.........................."

**Reubix** · 23rd May 2015, 20:32

Originally Posted by Mike.Gayner

Carb synchronisation seems to be one of those things that a lot of people leave to the shop because of the apparent need to specialised tools - vacuum gauge or manometer. I balanced the carbs tonight on my GSX in pairs using just a $2 piece of clear tube and some oil.

Shit pictures:
Hooked up - the air bubbles dissipated immediately upon starting the bike

Running - this pair were spot on, didnt need any adjustment

All up the process took about half an hour, and only minor adjustments were necessary. This method is more accurate than a set of Chinese gauges - you can't fool physics.

Ok, so how do you do it?