I installed the crank this morning, all went well.
Its a shame the prototype 60mm stroke crank came before the 62mm version as I would have like to have fitted the 62, however as my GT230 has always used a 60mm stroke maybe its a good thing.
I was a little concerned about the small chamfers on the oil seal races but the seals seem to have rode over them ok.
The conrods in the GT cranks all have an eye for an 18mm gudgeon pin and are all 110mm long. The rods can also be used with pistons that use a 16mm pin though because Richard has also made some step down little end bearings, the piston I use in my GT230 has a 16mm pin so I will be using one of the step down bearings.
the bearings come in two different widths, 20mm and 22mm. the one ill be using is the 20mm wide one as it works better with the wossner piston I use.
The bearings in this image are :
top left, standard 18mm for use with an 18mm pin
bottom left, standard 16mm for use with 16mm pin
top right, step down 18-16, 22mm wide
bottom right, step down 18-16, 20mm wide
in this image you can see how much thicker the little end bearings are, the two on the right are the GT step down bearings.
when fitting the sprocket and cush drive the spline was perfect as was the internal thread.
I then lapped the taper to find out if the taper was correct, as you can see in this image the grind paste marked the taper along the full length of the flywheel boss which shows the taper is bang on
the key sat in correctly allowing the flywheel to sit on the taper.
The heated mag race slid on and was tight
The crank pulled into the driveside bearing nicely and the mag housing went on nice too, the crank turned freely both while installing and after everything was tightened up.
Just waiting for the piston to come now before I try my hardest to twist and or brake this crank!
Maybe Richard can add some more info about the balancing, stuffers and the reason for the 18mm rod eye and when they are expected to become available along with the target price.
G.
