75 HP Bristol engine.

[Geoff Dowdle]

To tune the Solex correctly you have to balance the air flow of each carb
, and balance the vacuum on the idle system with in each carb .
If you have a 404/405 Workshop Manual there are details on how to do this .
Most owners use a Holden type air flow balancer and then just screw the
idle mixture screws in or out until the beat of the engine changes then
screw it out about half a turn ,this gets the idle mixtures pretty close.

But the 404/405 manual has detail instructions of how to make your own
triple Manometer , using this the airflow of the three carbs can be adjusted
together (as adjustment of the airflw of one carb can slightly adjust the
air flow of the other two ) . Once the airflows are matched you use the
triple manometer to balance the vacuum at the pilot jets , this is adjusted
by screwing the idle mixture screws in or out .
Then if the carbs are a matched set , jetted correctly and in good condition
you have a chance of tuning the old Solexes correctly .
IT IS WELL WORTHWHILE TAKING THE TIME AND VERY LITTLE MONEY TO MAKE YOUR OWN
TRIPLE MANOMETER.
Every 6 cylinder Bristol owner should have one.

Geoff