Shock swingarm bolt replacement?

[Grim]

Hi...

So I has a few hours, and now my wheel and swingarm are on the garage floor...

The long bolt holding the shock to the swingarm is bent like a banana. I am heavy, but I don't think this was me. Can I get a replacement?  Or what are the specs?

 

A few other observations:

The wheel bearing on the drive side of the wheel was loose, found it floating about in the bevel box after knocking the axle out.  It is 47mm OD.  It is knackered, so I'm slightly worried the 47mm replacement I have ordered will also be loose.

I pumped both UJs full of red'n'tacky, whereby it pushed all the old grease out, but on the spline zerk I felt like I was pumping forever and never saw any grease coming out anywhere. I wasn't too worried because I coated the splines before assembly anyway.

There is some slight rotational play in the driveshaft before it picks up drive, there is no play in either UJ, or the splines, so it that just the gearbox?

All in  all though, not a bad job, helps to have the tool kit, but nothing in the toolkit fits the big swingarm locknuts??? Are they just supposed to be hand tight? 😁

[docc]

Last question first:

Nope, the swingarm lock nuts should lock the pivots in the correct positions that center the swingarm and provide proper freeplay for the swingarm bearings. With the swingarm out, check the condition of the swingarm bearings.

The rotational play is normal. And additive. The V11 tire will roll some 2 1/2 inches/ 6 cm back and forth with the gearbox in gear.

Pumping the cavity of the driveshaft housing with too much grease can create a sort of hydrolock (greasolock?) for the two shaft parts to slide together as the suspension compresses. Might even make it impossible to slide the two parts back together to assemble.

Pretty sure I have the spec on that bearing, but will have to dig around a bit . . .

[Grim]

Thanks...I was only joking about hand tight! I used an adjustable spanner. I was surprised that nothing in the toolkit for is all.

Everything inspected and greased as I went, the only bad bearing was the one I mentioned, I have bought an SKF one which should turn up Monday.

 

What I really want is a not bent shock bolt!

Are they 8.8 high tensile, I got the length but not sure on the thread? Coarse pitch I would say.

[docc]

Early Workshop Manual shows the drive side wheel bearing as 20X47X14.  AFAIK, the later wheels used the exact same bearings. Source QUALITY bearings. I have settled on KOYO C3 after all of my rear axle bearing nightmares (internal spacer 1 mm too short!).

I don't see the dimensions of the bolt fasteneing the lower shock eye to the swingarm, but the PN is GU98610616. (Perhaps we can find its specification with that PN.)

With that bolt bent, do VERY CAREFULLY inspect the shock eye! They are prone to cracking/breaking!

[docc]

The shock mount bolt is 12.9 hardness.

The swingarm lock nuts are 30mm (I see that I had to add a 30mm socket to my toolset).

[Grim]

1 minute ago, docc said:

 

With that bolt bent, do VERY CAREFULLY inspect the shock eye! They are prone to cracking/breaking!

I suspect that already happened, as it's got an aftermarket shock in there.

 

I *think* SKF are decent quality, I went for SKF 6204-2RSH/C3

[docc]

I searched the Workshop Manual for a torque spec on those lock nuts, but no.

It does illustrate measuring the standoff of the pivot pins before removal with a caliper to return them to that position. I have painstakingly done this in the past, even using a laser to align the front and rear. Yet found that the swingarm is basically centered in the frame side plates with a slight relief of any lateral load on the center of the bearing race.

Good luck with your SKF. I also knew them to be "decent quality" before the last SKF (I'll ever buy) failed on me almost immediately. They lasted long enough to give me a 310 mile tow truck ride.

I now know that my rear wheel bearing spacer was 112mm and not the correct 113mm, but my bearings had been going 15-20,000 miles. Not a couple hundred! Upon comparing to the KOYO, the inner race of the SKF looks very "underbuilt."

[docc]

(Left to right: Romanian Koyo C3 / Xhinese "National" bought as Federal Mogul / Argentinian SKF ):

 

[Grim]

 

Thanks, I too used a caliper, had one side much further out that the other, so set it back as I found it! There might have been a reason.

So are you saying if I had just wound the pins in till resistance was felt, then back off a tiny bit, I would have been fine?

[docc]

3 minutes ago, Grim said:

 

Thanks, I too used a caliper, had one side much further out that the other, so set it back as I found it! There might have been a reason.

So are you saying if I had just wound the pins in till resistance was felt, then back off a tiny bit, I would have been fine?

That's a good question! At one South'n SpineRaid we declared the TechSession would be to measure the offset of every SpineFrame we could sneak up on. Thinking they would all be "offset" to the right - they were all over the place!

Then, the observation that the best set-up SpineFrames did not have their swingarms "offset."  I saw that my painstaking laser method had my offset something like 0.030".  I put that down to method error!

So, now I wind the pivots in until they capture the swingarm bearing inner races with equal tension and equal depth ("Standoff" of the exposed threaded portion), then relieve the lateral tension on the bearing (proper freeplay). That last bit from our trusted member @gstallons who deals with these sorts of things on a daily basis.

[docc]

@Grim, I see Gutsibits in the UK has a used shock bolt:

https://www.gutsibits.co.uk/pr/TheShop/index.php?q=98610616&f=d&Model=1&search=SEARCH

They also show the spec: M12 x 165mm (12.9)

[docc]

Now you have me wondering if you have a banana-shaped mount bolt, do you have a banana-shaped swingarm . . . Will a straight 12mm bolt slide through the mounting bosses of the swingarm?

[Grim]

1 minute ago, docc said:

Now you have me wondering if you have a banana-shaped mount bolt, do you have a banana-shaped swingarm . . . Will a straight 12mm bolt slide through the mounting bosses of the swingarm?

Good question, I think there's a bit of give on there (rightly or wrongly). If I spin the bolt the other end moves up and down, and the shock end also moves slightly. It may be worth looking out for a swingarm anyway as mine is terribly rusty.

 

Good shout on the bolt, I found a stockist of M12x160 12.9 (marine shop) so may try new as they're cheap.

[docc]

165 mm length, yes?

Also, best if not fully threaded the entire length, but whatever it is called when there is a length of smooth "shaft" before the threads  for the pivoting area of the shock and the two swingarm "bosses" . . .

[Grim]

8 minutes ago, docc said:

165 mm length, yes?

Also, best if not fully threaded the entire length, but whatever it is called when there is a length of smooth "shaft" before the threads  for the pivoting area of the shock and the two swingarm "bosses" . . .

Hmm, the Guzzi parts sites have it at 160mm, based on the part number, I wonder why the discrepancy. There is alot of exposed thread on mine come to think of it.