GSXR Spline Info

[lancer360]

Does anyone know the info on the spline for the transmission output shaft so I can make a drawing of an adapter? I know it is a 25mm 13 tooth, but obviously need more info than that for the machine shop. Really don't want to go with another Hawk aluminum one since I sheared the teeth of the last one and the steel ones from Peter D racing are on backorder too far to make my next race.

[Jnovak]

Get a transmission shaft.

taper grind it a about 1/2 the depth of the spline

machine 2 or 3 grooves around the shaft

remove the bearing shoulder

The shaft is now a simple broach

Press the shaft through a billet plate with a hole the root size of the shaft useing the shaft as a broach.

This will work with aluminum. Try 7075T6

[Christopher Crowe]

That's a fantastic "Indian Trick." I just learned a new technique!

Thanks,

Chris Crowe

[Rick Kean]

A Lo-Cost guy showed how the Hawk aluminum adapters are made to live with Hayabusas here

[lancer360]

Thanks! That is some good info. I got almost 3 seasons out of the first one and that was across 3 motors. Talking with some others we have come to the consensus that once you press the Hawk adapter on and then remove it and put it on a different motor it looses the press fit. This is most likely what contributed to my failure and the failures some others have had. So in the future for $75 I'll just plan on replacing it when the motor is pulled. Another F600 has been using a steel adapter made from a sprocket and his finally failed this weekend. Problem is since it was steel it took out the splines on the output shaft forcing an overnight engine swap. After chatting about it some, we think the aluminum one is actually the way to go and just replace it with the engine or even replace it each off season if you really want to be cautious.

Machining the shaft spacer some to allow more spline engagement is a good idea. The spacer looks to be made that length to hold the stock sprocket further out presumably to line up with the rear sprocket on a bike. We have to machine some of the length of the back side of the Hawk adapter as it is so taking that off the spacer instead sounds like a good idea. I was able to get mine off with a pair of channel lock pliers and just a little wiggling. Definitely wasn't pressed on.

[jim murphy]

And then yesterday Clint's car lost its ignition right at the S/F line - there went the race.

Jim