Carb sync

[johnbtrask]

I recentlypurchased a Carbtone manometer. I wonder if anyone can answer this question:

I have a box stock '83 Suzuki GS1100 ESD. The Suzuki manometer uses steel balls, and the factory manual says when synchronizing that the center two (2 and 3) should be 1/2 a ball diameter below the outer two (1 and 4). Do you have any idea how this would translate to the mm of Mg scale of the Carbtune?

[GooberPea]

I just got a CarbTune also. From the manual:

"On older Suzuki models with CV carbs (except GSX400F) the two outside carbs are set about 2.5 - 3.0cmHg higher than the inside pair. For specific model details consult your workshop manual or the Suzuki importer. (If the airbox has been removed set all the carbs the same)."

Craig

[BassCliff]

Hi Mr. johnbtrask,

You can also check out Mr. bwringer's "how to" on his website here:

http://www.bwringer.com/gs/carbsync.html

Thank you for your indulgence,

BassCliff

[Nessism]

My understanding of the reason for the different vacuum sync levels is because of the cross-over pipe in the exhaust system. If the bike has a 4 into 1 exhaust, you want to set all the levels the same.

Haven’t used a Carbtune before, but when using mercury sync gauges I set the level about 1cm lower than the outer cylinders when testing at 2500 rpm.

[doctorgonzo]

Nessism is right, it's because of the crossover. I just set mine slightly lower on my Morgan Carbtune.