Swinging arm bearings

I'm baffled. What might be going on with my 8v?

At its recent MOT, the tester showed me play at the rear wheel - it was quite distinct. He passed it but noted it. We had a look at mates workshop.

First thing when we got it in the bench was that there was very little play. That was odd, as I'd witnessed it.

So thought we'd have a look and tighten them up.

Took the plate off l/h side. The central spindle was loose, and wouldn't tighten - it just span. That's threaded in on the other side, right?

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The swingarm spindle goes through the swingarm and frame from the left hand side and screws into the right hand side of the swingarm. The bearings that are in the frame are preloaded by the castellated collar that is threaded onto the spindle.

I can't for the life of me imagine how brutal you would have to be to strip the thread for the spindle out of the swingarm!

Anyway, if it hasn't been done already it's way past time to take the back end apart for a looksee. Don't attempt to remove the swingarm with the bevelbox attached. That way lies madness!

Yes, it's going to have to be taken apart. I'm baffled, as the last time it was apart was for a clutch, a good number of years ago. And there was no brutality. But I just can't imagine how those threads would strip just in use. But it just turned and would not tighten up.

Trogladyte wrote:

Yes, it's going to have to be taken apart. I'm baffled, as the last time it was apart was for a clutch, a good number of years ago. And there was no brutality. But I just can't imagine how those threads would strip just in use. But it just turned and would not tighten up.

Did you do the clutch or somebody else? I have a feeling that the torque for the swingarm spindle quoted in the manual might be one of those ones that is wildly, insanely, wrong. If I'm remembering correctly and it's stupidly high then it may simply of been tightened to 'Book Spec' and stripped out.

I'll be interested to hear what's happened as this is a bit of a puzzler. If the swingarm needs repair a Timesert would be the best choice but I don't know if they make them that big?

My mate (professional Guzzi mechanic) did it with my assistance at his workshop. He has an excellent feel for these bikes, and has huge experience. So it's hard to imagine him stripping it out. But who knows. We're going to dismantle it in a couple of weeks when the tame automotive engineer is back from his hols, to avoid delays. I too am pretty keen to understand this. It's a 2008 that I've had from new, and it's got about 60k miles on it.

Oh yeah, and I totally agree on Timesert. I've left a message on engineer's old steam answerphone giving specs and suggesting Timesert. We'll see what we find, and what he says.

I'll update here on what we find.

Also interested in what you find, since Ive had mine apart, but for the purpose of the UJ joint, but did find the bearings needed replacing. More because they were dry and a little corroded. What a mission.
Hope it all ends up well.

Trogladyte wrote:

My mate (professional Guzzi mechanic) did it with my assistance at his workshop. He has an excellent feel for these bikes, and has huge experience. So it's hard to imagine him stripping it out. But who knows. We're going to dismantle it in a couple of weeks when the tame automotive engineer is back from his hols, to avoid delays. I too am pretty keen to understand this. It's a 2008 that I've had from new, and it's got about 60k miles on it.

Don't want to diss' your mate but it can be a pigs ear to align the heavy and sprung components to re-engage the pivot thread so I am hoping that it is not in the thread rather than stripped...

Good luck

But if not the sh prices vary wildly, the best i have seen are £160 and outside UK like this 1200 GRiSO swing arm in Italy

Sounds odd indeed cause there are 2 pinch bolts to keep it from rotating at all. Unless forgotten, then it could all unscrew.

Finally got round to this today. And it's no clearer why this has happened. The bearings were fine. The play in the rear wheel was from the spindle. There wasn't much left of the thread in the frame, so that's been repaired with a Timesert. But how this has happened remains something of a mystery.

Glad you have it fixed. Even if the pinch bolts were undone it is wierd for the pivot to unscrew what a bummer!

I guess you mean the thread in the swing arm not the frame? As the pivot goes through the frame and screws into the drive-side of the swing arm.

How much was that timesert? it is an unusual thread (fine and wide 20mm or so?)

Yes - the thread in the swinging arm.indeed. Don't know how much the actual Timesert was, but the job of tidying up the carnage and fitting the Timesert was 100 of your Earth pounds.

Interesting thread - Trogladyte could you share your "My mate (professional Guzzi mechanic)" details? Is it a fellah who moved to Leatherhead? I ask as I am in London and need to get some work done on my 2014 GRiSO (hopefully ready for sunnier days ahead) and I don't know one end of a spanner form another.........

Yes that sounds like the same fella. Is private messaging supported? I don't really want to post his phone number.

Thanks. Yes please do PM me - is his name the same as a famous Rowan Atkinson character?

Yes, we are on the same page. But I can't seem to do a pm. How does it work?

Found it. Sent you a PM.