Thanks for the kind words. For anyone that's intrested in trying the conversion it is a bit involved but mostly straight forward. The cylinder centers match up with the crank centerline of the CB77 so that made it possible to use the Suzuki GS400 top end. To get the through bolts to line up, the original through studs were removed and the holes closed with TIG weld. New holes were drilled and tapped after the upper crank case was milled out to allow the cylinder liner to pass through. New oil channels were milled into
the upper case to allow the use of the stud area to oil the top end as originally intended. The piston pins were reamed out to suit the Suzuki 16mm pins as opposed to the Honda's 15mm ones. A custom cam chain was created from bulk heavy duty 219 chain. The tensioner was converted from an automatic tensioner to a manual one to insure that the chain was properly tensioned. The top end was assembled as per normal. The breather at the top of the cam chain tunnel was blocked off. The CR72 style tower was put on the upper engine case and a gasket surface was machined into the case to suit. The transmission is a Nova 5 speed item with a lengthened mainshaft to accomodate the dry clutch assembly. The dry clutch is a combination of Yamaha TZ and Honda clutch parts. Ignition is handled by a Pertronics electronic ignition and the alternator is the stock item. Seat and tank are genuine CR parts. The hubs are also some genuine CR items. Rims are a pair of DID alloy rims from the '60s originally sold for the CR93. The CR seat and tank mount differently than the CB77 parts so new mounts were made up. The old ones removed and the new ones welded on. A CR petcock is fitted to the tank. As a CR item it has no reserve, so attention has to be paid to how far you've traveled, else you'll find yourself pushing the bike home. Carburation is by a pair of genuine CR carbs which are sand-cast magnesium items. The instruments are slightly modified Honda units. The speedo part is stone stock. The tachometer was recalibrated from the Honda 20:1 to the Suzuki 4:1 and then the whole bit put back together. The electric starter was retained, but when this picture was taken, I hadn't yet fitted the cover over the drive chain.
Ellis
