Thumbnail Filmstrip of Hilborn #57 Rotator Spool Images
Factory Hilborn rotator spool
This fits all Hilborn barrel (metering) valves
For small engines like 1 cylinder and motorcycles - Alky or Gas ok. ( not for Big Harley engines - use a #54 for alky or #56 for blown alky )
.100" wide ramp
These rotors are for the standard Hilborn metering valve. O-ring included. Choose from:
A - #57 Small motor on GAS 40-100 cu in or methanol for 1 cyl engines
B - #54 Medium to large motor GAS or ALCOHOL
C - #56 Medium to large motor, moderate to high percentages of NITRO. Slot width:
A = .100"
B = .187"
C = .312"