[Abbott]

Has anyone actually performed this? I have a TON of spare parts around the shop so I've decided to take this winter and build up a track bike for next year.

I have an '02 ST4S motor and a couple 748 frames. I've read that you can machine the cases thinner on the ST motors to fit the single sided swingers.

 

[belter]

the only difference in fitment terms is the swingarm pivot location and style.

 

[Abbott]

the only difference in fitment terms is the swingarm pivot location and style.

I read that the cases were wider at the swing arm pivot to hold the pivot bearings in them. They would need to be machined down thinner to fit the 748 swinger between the cases and the frame mount. I was just wondering if anyone had done this before and how they did it.

 

[belter]

I read that the cases were wider at the swing arm pivot to hold the pivot bearings in them. They would need to be machined down thinner to fit the 748 swinger between the cases and the frame mount. I was just wondering if anyone had done this before and how they did it.

plenty of people have done it. i've seen complete engines bolted to mill tables, to hacksaws and grinders. you'd want it to be pretty accurate.

you'll also need to get the bearings out, and possibly lower the bottom of the hole as the 916 pivot is quite a bit lower. you could do that fairly roughly i'd think. the swingarm pivots are located in the frame. they just need to be held in.

 

[ducvet]

Or go the opposite direction and use a st4s swingarm and modify your frame to suit you could use st suspension with a st swingarm or convert to cantilever and use a supersport rear end going for light weight. I personally would be more inclined to swap cases rather than machine and modify them.

 

[belter]

Or go the opposite direction and use a st4s swingarm and modify your frame to suit

and tell everyone it's an sbk prototype.

 

[Abbott]

Or go the opposite direction and use a st4s swingarm and modify your frame to suit you could use st suspension with a st swingarm or convert to cantilever and use a supersport rear end going for light weight. I personally would be more inclined to swap cases rather than machine and modify them.

can the ST4S cylinders/heads be used on the 748/996 cases? I recall reading another thread that the cylinder stud spacing was different.

 

[belter]

996 yes, 748 no.

 

[Abbott]

996 yes, 748 no.

that figures. I have a spare 748 motor, not a 996. sonofa!