I've had an ally swingarm off an S4 sitting here for nearly a year (it's an identical part number to an ST4S) waiting to go into my ST2.
The swingarm pivot, the ride height adjuster, and all the other odds and sods are also the same part numbers on the ST2 as they are on the ST4S - plus, the swingarm is exactly the same part number as the Ducati Performance ally swingarm upgrade for an ST2/4 so it should slot straight in.
BUT...and it's a big BUT
On an ST2/4 the steel swingarm has a couple of pinch bolts in front of the swingarm pivot that clamp the swingarm to the said pivot.
On the ST4S it just has a hole behind the swingarm pivot - that's it...just a hole straight through it. So, from the parts manual it looks as if there is supposed to be some sort of expanding nut type arrangement (oooeeerr missus) so that as you torque the swingarm pivot bolts up the cross section of the nut it's tightening on is conical - thus clamping the swingarm pivot. Does that make sense?
I've had the pivot bolt on back order for ages now with both Nelly and JHP and haven't got 'em yet (no disrespect guys, I know if Ducati sent them to you, you would send 'em to me) but I'd like to get to the bottom of exactly how the ST4S swingarm is clamped to the swingarm pivot. Chances are I don't need a specific Ducati part and I could get something suitable from a local engineering shop.
If only I could find a description anywhere of swingarm assembly/disassembly...
Having said that, having an ally swing arm is only bling (well it's a whopping pound lighter as well), the bike still has a perfectly good steel swingarm fitted so it's still on the road...I'd just like to get the ally one fitted if I can.
There's nothing of use in the workshop manual Jools, I've just had a look. The only other point of reference I'm aware of is the PDF spares chart on Ducati.com and that shows a rough outline but not a great deal more. If I get chance this weekend, I'll pop one out of my swingarm & get some photos & stick the micrometer on it to get some dimensions for you. HTH Andy
Ta mate...Oh, I'll have those master cylinders off you as well, send me a U2U with your addy, after all most of the bling on your ST2 ended up on my ST2. Might as well keep the tradition going and transplant your 4S master cylinders onto my 888
Just had a look at the parts manuals for the ST2 and the ST4s. The part no's for the spindles for both bikes are the same - so no problem there. The steel swinging arm is clamped by pinch bolts threaded into the swinging arm in front of the pivot from underneath. The alloy swinging arm has pinch bolts behind the pivot and entering from the top. The alloy is presumably too soft to take the torque required so there is a nut on the bottom of each pinch bolt, hence the holes. My bike is at home in the garage so I can't pop out to have a look to confirm that but it is pretty obvious from the parts list.