Jeez Brad, you better get onto the Tour de France lollies if you want to race every class on the program
. However, the pre 60 class has for a long time been the poor bastard son of the sport but for some weird reason there's a bit of movement out there in Mancave City with a number of pre 60 class bikes being resurrected or built from scratch. For a while I've had a nice ex USA flat tracker Triumph T100SC engine which was originally intended to replace the pissy 250 Ducati single in my Hindall but my mates have rightly talked me out of that little deal on the grounds that I'd be buggering with the only Ducati frame Harry Hindall made. So, when Jonesy started to build his big dollar 1959 GP Monark I decided to build the opposite, a low budget pre 60 TriBSA using a different than traditional set of components. Housing the Trumpy engine is a BSA C15 frame, with Norton Roadholder forks, BSA Goldy front wheel and a Harley Davidson Sportster back wheel. It'll be topped off with a BSA B44 GP tank and the usual alloy guards. I'm hoping to have it up and active by the Nats in November, or if I'm industrious enough, the Canowindra HEAVEN round in October.
But, enough of my project and on to some suggestions for you Brad. Your need for a left foot change or conventional one down, four up right hander has made it a tad restrictive but I think I've found one that might just fit the criteria.....................
Honda CB72 250/CB77 305 .
This engine is the basis for countless road racers in it's early-mid sixties form but the pre 60 version while being a bit different can be easily upgraded internally to the latter specification. Even though the engine features a conventional left side, one down three up shift pattern the big no-no for many is that the very early Honda Dreams had a rotary gearbox where if you're not on top of what you're doing you can up change from top back to first with the dual consequences of an over the bars experience and a catastrophic engine over-rev causing all sorts of haemoraging
(see DTs AJS photos for details). Luckily Webco made a neat little blank off plate of which I have one so if you decide to go the Honda route...I'll gladly supply it as a template to make one. Tons of go fast goodies are available for these engines thanks to the road racers, even down to genuine factory race parts such as 5 speed gearboxes and exotic clutches. The road racers have achieved serious horsepower from these motors and the 305 can be bored and stroked to 500cc. Aussie Tony Gill actually won Classic Daytona on Billy Snellings 500cc Honda CB77 10 or so years ago.
The CB72 frame is pressed steel backbone with tubular rear subframe with the motor as a stressed member. Some serious frame strengthening is needed or, fit the engine to a BSA or similar Brit frame.
The class 1959 model CB 72 
tHE '67 CL scrambler version showing the stronger frame based on the earlier version. 
1959 Greeves Hawkestone: 
or..a GRUMPH....a '59 Greeves with a unit T100 Triumph motor: 
OR, Combine all of the above and fit a Honda motor in the Greeves frame!
