NAMBA March 2021 Web

Rob also ran a rear drum valve in his earlier designs, but changed to a front rotary valve. Because the new front intake MB 40 with its large diameter crankshaft can have the same intake flow with lower friction, that layout is becoming more common in newer engines. 24 March 2021 PROPWASH Bell Valve Bell Valve with Balancing Cut and Backplate Bell Valve and Drum Valve Backplates for the Allen 90 Early MB 40 Rob went through several changes before the current version. Combined with a fat tuned pipe, this is probably the most powerful 6.5 cc nitro engine available, especially on a non-nitro, 80% methanol and oil fuel. MB 40 Assembly Late Model MB 40