Worlds only Balanced Piston engine chain saw.Saw was sold for a very short period of time and then withdrawn from the market.
The BP1 saw was 20 years ahead of it's time .It had a dual piston desing for balancing and porting of the engine. It would run WOT 12,000 RPM and a failure in the governor assembly could result in an engine burst and injury to the operator. McCulloch recalled all the saws and they were destroyed. There is only a few that did survive.This is one of them very rare saw.
The Technical: Not too many have seen the internals of this saw...some pictures will help you understand the design.
MANUFACTURED BY: McCULLOCH MOTORS CORP. LOS ANGELES, CALIFORNIA, U.S.A.
INTRODUCED: 1962
DISCONTINUED: 1963
DISPLACEMENT: 2.7 cu. in. (44cc)
BORE: 1.75 in. (44.4mm)
STROKE: 1.125 in. (28.5mm)
CYLINDER TYPE: Aluminum with cast iron sleeve
H.P.: 4.2 @ 10,000 RPM
RPM: Goverened at 12,000
CONSTRUCTION: Die cast magnesium
CHAIN:McCulloch Auto-Mac with built in sharpener