Swing arm shims/washers

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Steve Brown
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Joined: 12 Nov 2007 23:44
Location: Leicestershire

Swing arm shims/washers

Post by Steve Brown »

Hi all, about to re-assemble the swingarm on mine and would like to put right a bodge I made (20 0dd yrs ago) the first time I owned this bike :oops: I seem to recall losing track of the correct washers spacing the swing arm laterally, then making it up as I went along :roll: It wasn't a good job as I can now see. :roll:
The parts list shows a single washer, but I can't see which side it sits. eg. chainside or t'other. To save me time does anyone know which side it should be?
Obviously, if wrong the wheels will be offset a little.

Time for bed now, I'll check back tomorrow,


Steve
EVguru
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Post by EVguru »

The side clearance is set by adjusting the swing arm spindle (flexing the side plates slightly) and you only need a washer if the clearance is excessive.
Paul Compton
http://www.morini-mania.co.uk
http://www.youtube.com/user/EVguru
Steve Brown
Posts: 1401
Joined: 12 Nov 2007 23:44
Location: Leicestershire

Post by Steve Brown »

Thanks Paul, will have a play with it. There were washers/a washer there originally, but in the not ideal conditions of stripping it down in my single mans accomodation in RAF Germany I rushed it between inspections and had to spend as much time hiding the bits from the SWO (Station Warrant Officer) as working on it. I was inspired by the old Colditz/Great escape films. I never did get caught, but the aroma of Gunk had him going for a while, he was convinced I was using drugs or running a still! Ahh, happy days.
Steve Brown
Posts: 1401
Joined: 12 Nov 2007 23:44
Location: Leicestershire

Post by Steve Brown »

Been looking at the job again tonight. Paul, can you explain how the side play is adjusted by turning the spindle, please? It appears to me that once the spindle is bottomed against the shoulder on the smaller threaded end, any further application of force will only serve to spring the outer plates apart? As the side play is limited by the centre plates this won't change anything-play wise and only applies stress pointlessly to the outer plates.
I remain convinced that washers or shims between the swingarm bushes and the inner plates are what is needed, and that I only need to decide whether they should be placed to one side or the other, or to centralise the swingarm. I'll just have to check the wheel alignment and go from there, I suppose. Laser shopping tomorrow then.

Steve
dunk 1
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Post by dunk 1 »

took mine apart at christmas to repaint the arm and it had one washer on t'other side - ie away from the chain- Duncan
dunk
Steve Brown
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Joined: 12 Nov 2007 23:44
Location: Leicestershire

Post by Steve Brown »

Thanks Duncan, I'll start with it that way round then. It does look as if the makers intended a single spacer as the parts list shows it that way, and I'm sure that's all mine originally had.
Of to DiY outlets now to look for Lasers. There was a good article in Classic Bike recently about making your own wheel alignment kit using lasers (April issue) For years I've struggled with boards or lengths of metal that don't fit round stands etc. Then I had a bike put on the Laser kit at a shop and the difference was quite surprising. It looked accurate enough with the traditional method, but after lasering it the bike felt completely different, and the discrepancy on the chain adjuster bolt was only 0.5mm or half a turn!
maybe this is another topic though?

Steve
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Post by EVguru »

You're not alone in not understanding how the adjustment works.
It appears to me that once the spindle is bottomed against the shoulder on the smaller threaded end, any further application of force will only serve to spring the outer plates apart?
Correct, but if you unscrew the spindle slightly so there is a gap beween the shoulder and the outer plate, you will pull the outer plates in as you tighten the nut on the smaller threaded end.
Paul Compton
http://www.morini-mania.co.uk
http://www.youtube.com/user/EVguru
Steve Brown
Posts: 1401
Joined: 12 Nov 2007 23:44
Location: Leicestershire

Post by Steve Brown »

Hi again Paul, thanks for clearing it up for me. Unfortunately mine has more clearance between the outer plates and the arm than the inner plates and the arm. If I pinched it up as described, it would be an awful lot of movement on those outers. My own personal mech. sympathy level won't let me! So I'm going with what I think the original set up aimed for. I.e. shimmed against the inner frame plates and the spindle snugged up against the outers. I'll end up doing it all again sometime in the future anyway, as the brushed smoothrite paint on top of the old finish will eventually offend even me, and the well corroded spindle and seen action bushes will have their own reasons for replacement too. I'm not spending the money on a proper resto for a long time yet. Too many other money pits on the go right now.
Sorry if this topic keeps cropping up, I just found out how to do a search and read your earlier explanation of this subject. Tch! Newbies eh?
Off to the nut and bolts and laser shops now,

Thanks again,

Steve.
EVguru
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Post by EVguru »

Where the clearance is large, then by all means use a shim/washer. I've got several pre 'K' frames and none has a shim, but most 'K' frames I've seen do. It will be a production tollerance thing.
Paul Compton
http://www.morini-mania.co.uk
http://www.youtube.com/user/EVguru
Steve Brown
Posts: 1401
Joined: 12 Nov 2007 23:44
Location: Leicestershire

Humble Pie time

Post by Steve Brown »

Why can't I learn to listen? Paul, I owe you an apology, will a beer or whatever you drink at Cadwell do? I went shopping, called in at NLM, and talked it through with Stuart. He said exactly what you had, which meant I needed to go back armed with shims and look at mine a bit closer.
Sure enough, when I did the swing arm back in '79/80, I must have been drunk and turned the spindle the wrong way :oops: The outer plates were bowed outwards, hence the excessive clearance there. So I applied the technique as you/Stuart described, and guess what? Those plates pulled straight back in! Surprised me how easily too, so doesn't surprise me how easily I could have mangled it back then :oops:
Anyway, all back together now thanks. It always seemed to steer/handle well enough, maybe I'll be really impressed now :shock:

Steve.
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