FD Change Question

[XSive_speed]

Maybe this is more trouble than it is worth, but I've got to ask. Has anybody tried taking the gear set from a 650 or 750 and installing it into the XS 1100 housing?

I'm asking because if the original 1100 housing could be used, it would save the whole business of extending or adding a bushing to the 1100 drive shaft when installing a 650 FD.

Maybe this is discussed in a thread somewhere, but I didn't run across it.

Thanks,

[CatatonicBug]

Well, since changing the gearset would require splitting the cases (assuming you want to replace ALL the gears in the tranny), it seems to me that adding a little bushing is a LOT easier.

[XSive_speed]

I'm not so much thinking about the tranny or middle drive, but rather just chaning the pinion and ring gear in the final drive. I don't actually know if the ring and pinion would work if moved into the 11's final drive housing.

I would have to play with the shimms to get the FD pinion properly blueprinted with the ring. I just don't know if it has been tried (I assume so), or what the results were.

[natemoen]

Talk to 3phase, he has tried most everything possible with the different final drives.

And I assume you mean the 750-850 final drives since the 650 is chain driven.

[3Phase]

Just get an XS850 final drive and don't mess with it.

John, I don't think the XJ650 final drive would fit and the XS650 uses a chain and sprockets.

Assuming you pick up an XS750 or XS850 final drive, the parts you would want to swap are the input couplers and that really can't be done. The input pinion shaft diameters and the numbers and shapes of the splines are totally different. The couplers will not interchange.

You can't cheat and swap the entire pinion assembly, either, because the pinion gears will not mesh with the ring gears.

The XS1100, XS850 and XS750 final drive housing castings have different casting and part numbers but they might interchange and they're all marked at the factory with the tolerances for setting up the gears and bearings.

Any of the final drive side cover castings will physically bolt up to the final drive housing castings but that's not particularly useful, either. The XS1100 side cover is the strongest of the side cover castings but it won't seat all the way down over the XS750/XS850 side carrier bearing. Yes, it could be re-machined and then you could use the stronger XS1100 side carrier bearing on the XS750/XS850 hub to get rid of the weaker bearing but you could buy a couple of complete bikes for what that would cost.