Stock wheel & speedo drive

So that problem solved the whole lot still binding.

The left side calipers now seem to be a fraction too tight going on, the bottom doesn't slide nicely in, so might have to relook at the fitment of the disc on that side as nothing should have changed on the left, same spacer so the disc mounting is the only thing that has changed.

On the right the point about that small washer from Piet seems to fit with this 'pumpfteenth difference'. Wonder where to source one of those :unsure:

The right is ok but not what I would call perfect, trial and error I guess!
 
Carlo, I assume from the photo of the socket head bolt, that's is what you're using to bolt the disk carriers to the wheel. If so, then there's the source your bolt clearance problem with the speedo drive. They have a thicker head than hex head bolts. Check out Andy's photo in post #2. He has hex head bolts.
 
cbertozz said:
The left side calipers now seem to be a fraction too tight going on, the bottom doesn't slide nicely in ...
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Not sure what you mean about the bottom not sliding in.

Anyway, just make sure the caliper joint face (where the two halves of the caliper bolt together) is centred on the disk on both sides. If it isn't, then either your wheel spacing is messed up or you need to shim the caliper mounting bolts.

Are you replacing the front wheel with another, or just re-fitting the speedo drive?
 
Just thinking aloud: if someone used extra washers in the past then possibly the non-standard bolts were a bit long... is it a blind hole? Might pay to check if you just remove the washers.
Apparently you can do a bit of damage if your bolt’s a bit long, or so I’ve been told. I wouldn’t know, I was never a big boy...
 
The small version of the washer doesn't look much bigger than the step on the wide-to-narrow part of the axle, so I'm wondering if it makes any diff. if the axle deforms itself into the housing, why wouldn't a steel washer of the same size do the same. A wider OD washer would certainly spread the load onto the speedo housing a lot more effectively.
 
Quentin,

If the speedo drive did not have this washer, ie, a hard surface upon which the axle step bears, the soft alloy would deform quickly, leading to all sorts of issues regarding fitment/removal of the axle. I see this on almost every drum-braked 750, which does not have such a washer. The axle has often been pulled into the alloy, which deforms and jams the axle, making it often impossible to remove the axle without the use of a bloody big hammer! The mangled and rusted axle ends are often tesitmony of how long this has been going on.

Even with the washer in place, it is often difficult to remove the axle because some ham-fisted backyard bodger was scared he'd lose the wheel! I spend a lot of time during tyre changes just to get the axle moving freely in the wheel/fork assembly. Chasing threads and cleaning up mangled axle ends is only part of the game. Burrs develope at the step in the axle, damaging the slider bores every time the axle passes through.

If the wheels and speedo drives were fitted with more patience, the axles kept in good shape, the fork sliders correctly aligned with straight mudguard brackets, I'd have a lot more fun fettling these old clonkers. But no, every second front end seems to have been assembled with a lump hammer... fucking amateurs!

piet
 
It's easy to damage the thread if you go full caveman on it. A mate had a KTM dirtbike that seized its axil once, that took some serious wacking with the FBH with its packed up on its side with solid timber to get it out. Mine gets some waterproof greace every time after that painful effort.
 
Dellortoman said:
Blimey Piet, I wouldn't have thought it possible to bugger up an axle installation so badly as to damage the axle.
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You should have seen the state of the axle threads on my poor little Vento when I got it, Cam. Jeez ... Hammered to buggery. Shocks me that anyone could have such a lack of mechanical sympathy.
 
Truly astounding - the world of hamfistery is not a pretty one. I've had to deal with it many times over my years as a mechanic as well. Maybe salted roads in Eu is a contributing factor - haven't seen too many as bad as what you describe, Piet. But nothing surprises me.

I wasn't doubting the efficacy of a steel washer, just wondering if a larger OD steel washer would be better, as it would spread the load over a wide surface area of the soft speedo housing.
 
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The trick is not to overtighten the axle nut, it's main purpose is to bring everything into alignment. The pinch bolts do most of the work.
 
You'll never be able to use those allen head bolts. To provide recess for the key the head is too deep, or those washers. They must strike the speedo gbox. You need normal hex head bolts (h/t) and lock tabs.
 

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