Greasers

Paul Marx

Paul Marx

Hero member
Location
France
Don't worry, not a new music or fashion thread!

Maybe 3 or 4000 km back, I changed the swingarm spindle and complete needle roller kit on my SF2. Packed the whole lot with grease, checked, no play.

This weekend, whilst cleaning the machine, shit! Quite a few mm of play at the rear wheel and no, not wheel bearings or lateral play at the swingarm spindle. Pumped full of grease in there via the nipple which I'd intended to do in the first place, and hey presto, no more discernable play.

Is this normal?

Ciao
Paul
 
Not at all normal to flog out a set of needle rollers in rapid time. Check that the spindle is well and truly tight. It is more likely the inners loose on the spindle and not tightened between the frame.
 
Tippie said:
Not at all normal to flog out a set of needle rollers in rapid time. Check that the spindle is well and truly tight. It is more likely the inners loose on the spindle and not tightened between the frame.
Click to expand...

Nope, no lateral play. Swingarm spindle shimmed up and well and truly tightened up, it's radial play on the spindle/rollers which disappears under the hydraulic effect of the grease.
Ciao
Paul
 
Paul - you say you replaced the spindle as well as the bearings.  Was there a reason for changing the spindle?  Did the spacer get swapped out too?  I assume you replaced the dished washers that hold it in place between the bearings?  If the hardened bushes were the correct OD for the needle roller bearings that only leaves the fit between the bushes and spacers...if tightening up everything removes axial play that surely suggests an incorrect dimension if radial play results.
 
Just looking for a good excuse not to get back in there, much too much overdue bike work scheduled for this winter.

Looking back, I didn't change the spindle. I bought a set of rollers from Wagner and reused whatever spacers and washers were in there.

The hydraulic effect of the grease stops any play until the grease seeps out obviously.

Will have to do until darkest winter.

Ciao
Paul
 
Sure enough, after 50 km, play is back at the rear end, hydraulic lock effect gone, so will have to investigate when the riding season is calmer.
That and changing primary chains and clutch rubbers and welding up (again) the instrument holder.

Plus work on the other bikes.
Will have to get organised and find something to keep the girlfreind happy!

Ciao a tutti
Paul
 
Paul,

Just a suggestion - use a marine-grade grease on the new bearings/bush.
I use Mobil XHP221 (XHP222 might be even better), it is almost impervious to water.
Same for the steering head bearings.
It will last donkey's years with that stuff in - squirt some new grease in from time to time if you are able.
 
SimonR501 said:
Paul,

Just a suggestion - use a marine-grade grease on the new bearings/bush.
I use Mobil XHP221 (XHP222 might be even better), it is almost impervious to water.
Same for the steering head bearings.
It will last donkey's years with that stuff in - squirt some new grease in from time to time if you are able.
Click to expand...

Thanks, why not?
Paul
 
Well got the swingarm out yesterday. Need to investigate closely.
Need to push bearings out and check if the inner washers are there.
A miracle has led me to find the used parts I changed last time around in the stock of parts I managed to save from an ongoing divorce. There is at least one fine shim/washer in there.
I haven't however got all my workshop docs so have a question.
The inner washers show up in the Green Book diagram, in Andy Wagners online catalogue as a triple feature but not on the 750. I don't have the 750 specific parts list, are the washers in there?
Thanks
Paul
 
Paul,

The washers are only meant to provide a positive stop for the bearings, the bore for them is only slightly larger than the ID of the swingarm pivot tube and the bearings have a huge radius at their edge.  As the fit is so tight, there is no real need for them, they do not position the inner spacer.

Quite common for the needle bearings to give up quickly.  Not really an ideal design for this application, especially with the crude Laverda sealing system!  I have modified mine to fit an oil seal.  Makes initial greasing a pita as neither air nor grease manages to make its way past the seal, but the bearings do last very much longer, about 10 seasons in the 3C so far.

Won't find the washers in a 750 parts book, the needle bearing set-up was introduced only after the twins dropped out of production. :D

piet
 
Ok, it appears I've found at least part of the problem.
One of the bearings is a loose fit in the swingarm, it actually drops straight out whereas it should be  a nice tight fit. The other one will need driving out.
Play on the loose bearing is minimal but amplified by the lever effect at the end of the swingarm, I imagine that would be sufficient to explain the 3 to 5mm play there.
Any easy remedies? Will Loctite bearing glue do it?
Thanks,
Paul
 
sfcpiet said:
Paul,

The washers are only meant to provide a positive stop for the bearings, the bore for them is only slightly larger than the ID of the swingarm pivot tube and the bearings have a huge radius at their edge.  As the fit is so tight, there is no real need for them, they do not position the inner spacer.

Quite common for the needle bearings to give up quickly.  Not really an ideal design for this application, especially with the crude Laverda sealing system!  I have modified mine to fit an oil seal.  Makes initial greasing a pita as neither air nor grease manages to make its way past the seal, but the bearings do last very much longer, about 10 seasons in the 3C so far.

Won't find the washers in a 750 parts book, the needle bearing set-up was introduced only after the twins dropped out of production. :D

piet
Click to expand...

Hi Piet,
At least the washer mystery is cleared up.
Surely the SF3 had the needle bearings?
Ciao
Paul
 
Paul Marx said:
Ok, it appears I've found at least part of the problem.
One of the bearings is a loose fit in the swingarm, it actually drops straight out whereas it should be  a nice tight fit. The other one will need driving out.
Play on the loose bearing is minimal but amplified by the lever effect at the end of the swingarm, I imagine that would be sufficient to explain the 3 to 5mm play there.
Any easy remedies? Will Loctite bearing glue do it?
Thanks,
Paul
Click to expand...
Paul, if you cannot replace or repair then Loctite 638 retainer will stop 0.25mm of play in the bearing shell.
 
Ok, both bearings refitted with Loctite 638 yesterday. One just slipped in, the other needed the swingarm heated up and a bit of tapping.
Left to harden 48 hours and will put swingarm back in tomorrow.
We'll see.
I don't think that the play had any incidence on a machine used for touring since there was only a few mm noticeable at the back wheel. More a question of intelectual satisfaction. If it isn't cured with the Loctite, we'll see next winter. Simplest would probably be to hone and have some bronze bushes made up.
Ciao
Paul
 
Well all done!
One of those awful succesion of mishaps where jobs that should have been done over a few weekends have taken all winter.

The swingarm had come out easily but no way would it go back in.
Literaly blood, sweat and tears for hours until I thought it would be a good idea to loosen the rear engine mounts so as to let the frame spring apart some.
The swingarm just slipped straight in!

Now need to do primary and secondary chains on the Electronica, track day in 3 weeks time.

Ciao
Paul
 
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