So last week I decided to treat myself to a new set of clutch plates. the old ones were starting to show signs of wear. Not slipping, but getting a bit 'graunchy'. Bought a set of friction plates, and set to. I've had plates out on Ducati dry clutches many times before, but this time, for the first time, after I'd unscrewed the 6 turret screws and started to pry the pressure plate away, the plate separated from the push-rod. The push-rod seems to extract 'so far', then stop. Anyway, the push-rod bearing in the pressure plate looked to be in OK condition, it rotated smoothly and easily. I hummed and hawed as to whether to grab the push-rod with mole-grips and pull it out, but in the end decided not to. Anyway, removed the old plates and I wasn't too convinced by them; the fact that there were two plain plates together at the front of the pack as well as at the back didn't seem right to me. Anyway, all looked OK, including wear on basket grooves. Fitted new plates, and noted that I now only needed one plain plate in the front of the pack, which still allowed just enough space for the teeth on the pressure plate to engage with the hub. So all was replaced, and the pressure plate tapped gently into the push-rad with a mallet, and it all seemed to go together without need of undue force. Road-tested and clutch operation seems fine. So my questions is this: should I be concerned about the push-rod? Does it warrant further investigation and/or replacement, even though the clutch seems to work fine? I wonder if it is bent a bit somehow. I do have an aftermarket slave cylinder fitted, but it has been on there for years and has always worked well. I did fit that myself, many years and miles ago now. I'm struggling to recall, but I have a vague feeling the slave had a short push-rod of it's own, just an inch or so long?
Nothing to worry about. The push rod should not actually be stuck in the bearing but often is due to clutch dust and/or corrosion. The way to remove the pushrod, if needed, when what happens to you happened is to remove the slave cylinder and pull it out from the other side. It’s all good man
Sometimes they need a gentle tap as said. I can't speak for Ducati but would think it's originally a transition fit - i.e. N7/h6 and I always think it's a blessing if it's still tight as otherwise a scenario exists where shaft is spinning and entire spigot bearing is stationary resulting in eventual replacement of pushrod (or resorting to Loctite or similar).
In layman’s terms Chris do you mean a tight fit? And what’s N7/h6 please? Every day is still a school day. TIA
Paul, this explains it quite well https://blog.misumiusa.com/shaft-hole-tolerances-for-clearance-interference-fits/ sort of stuff you learn as an apprentice machinist or design engineer
Evening guys, sorry to drag up an old thread but I'm in the process of changing my control arm and push rod, the old control arm on my ST4 (916 engine) has pushed its way through the slave cylinder first and then the push rod which fits into the bearing on the pressure plate, the old rod was right in the engine and took some persuasion to remove, the new parts have arrived but im unsure whether or not to grease them and with what grease, I can't seem to find anything about this anywhere.
Great, thanks for that, the old one came out caked in crap so not sure what the previous owner had on it.
