Correcting alignment of cylinder bore to crankshaft

When Norton went from 650 to 750 then moved the cylinders backward to accomodate the larger bore. But they did not realign the cylinder bore with the crankshaft center thus causing more vibration, more piston skirt wear and strain on the components. Instead of the cylinders being behind the crank centerline – they should be in front of it – ideally 1 or 2mm in front. This is called “Desaxe”. The JS wedge base gasket achieves this by moving the cylinder centerline approx 1 mm in front of the crank center giving you a more reliable and longer lasting motor with increased performance.

The image below shows how the wedge base gasket tapers in thickness from one end to the other (use yamabond sealer). To restore compression you should go to a thinner .003″ or .021″ JS head gasket. Its a drop in gasket. All the cylinder bolts and nuts screw in just fine.