This How-to describes the process of setting the float heights for the BDS26 and BDS28 Carburetors.
Preliminary Float Height Setting (Benchtop or dry Method):
After a thorough disassembly and cleaning of the carburetors, you should set the float height on the bench. This is used to get them in the ballpark before setting them using the more-accurate wet method.
For US/Australia Seca II Carbs (Mikuni BDS26):
Here's the procedure as laid out in the FSM: The factory specification for dry float heights is 6.2 to 8.2 mm or 0.24" to 0.32".
The specified range for float heights is 6.2 to 8.2mm. I chose to average these two and set them for 7.2mm:
I used a dial caliper with a depth gauge to verify this setting. I set the caliper to 7.2mm and locked it.
Measure from the gasket surface to the top of the float. The float height should be beneath the edge of the caliper. This measurement should be taken when the float just contacts the float-needle. The float needle should not be compressed. In the following photo, the float heights are too high and need to be adjusted.
To adjust the float height, remove the float pin and remove the float:
The location of this tab sets the height of the float:
Grasp the tab with a pair of pliars and very carefully bend it. Bend it in small increments; a little bit goes a long way:
Refit the float and remeasure the height. Continue to remove and adjust the tang until the float level is within spec:
Repeat for all four carburetors. After the carburetors are installed on the bike and connected to a fuel source, use the wet adjustment procedure to finalize the float levels.
For European/Canadian XJ600/Diversion Carbs (Mikuni BDS28):
Here's the procedure as laid out in the FSM: The factory specification for dry float heights is 11 to 13 mm or 0.43" to 0.51".
Fuel Level Setting (Wet Method):
Coming soon.