Panther

Panther flywheels employing a crankpin with a taper press fit design are prone to suffering from enlarged crankpin holes. The Alpha Bearing references P2 and P3 are manufactured very slightly larger than the original Panther design. This measure ensures that the vast majority of flywheels can be assembled and benefit directly from the correctly fitting replacement crankpin. Special care should be taken when assembling cast iron flywheels, as used in Panther engines, as over tightening the crankpin nuts will cause the flywheels to crack. Should the flywheels crack this will render them unserviceable.

250cc

Year	Model	Con rod casting No.	Big end Part No.	Cage Part No	Small end Part No.	MAIN BEARINGS
						Drive Side	Timing Side
––	O.H.V Models	––	––	––	––	––	––
1933-47	10, 20, 40, 60, 70, Red Wing	WP 565	P1	––	SE63	R3 (Bush)	R3 (Bush)
1947-55	M65	WP 4372	P2	––	SE63	R3 (Bush)	R3 (Bush)
1956-60	M65	WP565	P4	––	SE63	R3 (Bush)	R3 (Bush)

350cc

Year	Model	Con rod casting No.	Big end Part No.	Cage Part No	Small end Part No.	MAIN BEARINGS
						Drive Side	Timing Side
––	O.H.V. Models	––	––	––	––	––	––
1935-37	80, Panther, Red Wing	WP804	P2	––	SE63	R3 (Bush)	R3 (Bush)
1937-55	30, 70, M75, 80, 85, Red Wing, Panther, Stroud	WP804	P2	––	SE63	R3 (Bush)	R3 (Bush)
1947-63-	M75	WP4372	P4	––	SE63	R3 (Bush)	R3 (Bush)

500, 600 & 650cc

Year	Model	Con rod casting No.	Big end Part No.	Cage Part No	Small end Part No.	MAIN BEARINGS
Year	Model	Con rod casting No.	Big end Part No.	Cage Part No	Small end Part No.	Drive Side		Timing Side
1932-53	90, Series K, 95,50, Panther, Red Wing	460/325 or 452	P3	––	SE65	RLS11	LS11	LS11
1950-55	All Models	5396	P3	––	SE66	RLS11	LS11	LS11
1956-64	Model 100	5396	P6	––	SE66	RLS11	LS11	LS11
1959-66	Model 120	––	P6	––	SE66	RLS11	LS11	LS11

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