Wheel Building

[Robert Watson]

You should also look to see how much stove enamel is in between the spoke flange and the brake drum. The one I just took apart were metal to metal where bolted but toward the outer edge of the machine diameter there was a varying amount of paint under the flange.

 

[greg brillus]

Never good to have paint on any of those surfaces, same as the rear sprocket........it just acts like a gasket that can eventually break up and start movement.........It all goes down hill from there.

 

[Magnetoman]

You should also look to see how much stove enamel is in between the spoke flange and the brake drum.

Never good to have paint on any of those surfaces, same as the rear sprocket......

I'll check the paint thickness when I have it apart later today or tomorrow, and I won't apply new paint where it doesn't belong.

I partially disassembled the rear hub yesterday, removing the brake plate and exposing the tapered bearing.

At this point the 10 H19/1 hub bolts also are revealed (only 5 are shown in the drawings, presumably for parts dating from an earlier age). I'm guessing that the portion of the bolts that fit in the brake hub are knurled in some way to keep them from turning when the nuts are attached. The next photograph shows how close these nuts are together, having evolved from the earlier 5-bolt pattern which would have given them a more generous spacing,

Based on the above, I don't see why there would be any particular problem fitting the spokes before tightening the flanges. That is, it doesn't appear there would be an advantage to having a sufficient gap between brake hubs and spoke flanges to insert the spokes after the flanges were tightened. Unless, of course, a spoke needed to be replaced in a wheel that was already laced. Comments?

On the other hand, apparently some people use a spacer (shown in red) to allow room to install and remove spokes.

However, the steps in the hollow axle noted with arrows provide hard stops for the bearings, and the brake plates provide hard stops at the other end. The H17 shims correct for production tolerances to give the desired end float. Unless the red spacer is thin enough that the correct end float can be achieved with no, or thin, shims, a red spacer is a bodge, not an option. Again, comments please.

Note that in the above drawing I've replaced what is shown in the Alternative Spares manual for the bearing and shims with what is in the Vincent spares manual. The inset below is from the Alternative manual, showing a "spacer" next to the bearing, which isn't shown in the Vincent manual, along with what are probably the K17 shims, although they aren't called out with part numbers.

 

[Robert Watson]

The heads on those bolts are eccentric which locks them against the side of the hub.

The brake drum is independent of the bearing end float. I have changed a broken brake drum "on the road" and just had to change the shimming between the outer end of the bearing and the brake plate to make sure the backing plate clears the drum.

10 bolt hubs were I think introduced with the Shadow's massive increase in horsepower! With todays much improved brakes I would be more inclined to want 10 bolts on the front hubs!

 

[Magnetoman]

The brake drum is independent of the bearing end float.

That can't be the case. The brake drum is rigidly attached to the H38/4 hub, which holds the outer race*. This means the brake drum moves back and forth by the same amount as the bearing, i.e. by the end float of the bearing.

*corrected: I originally wrote inner race.

 

[bmetcalf]

The hub holds the outer race.

 

[Robert Watson]

K17 actually is the rag in the tool kit! I assume you meant H17 for the shims.

Also the unknown spacer was required when the narrow roller bearings were used in lieu of the wider more common ones.

That can't be the case. The brake drum is rigidly attached to the H38/4 hub, which holds the inner race. This means the brake drum moves back and forth by the same amount as the bearing, i.e. by the end float of the bearing.

No sir, I'm afraid not. The shims that control bearing end float go between the shoulder on the axle and the inner race of the bearing. the flange to which the drums are affixed are integral with the hub. To take it to and extreme you could put a 1/2 in wide "shim" between the bearing inner race and the axle shoulder and the brake drum would still be in the same place, but the bearing would have moved 1/2 in. Mind you there would be a lot of bearing clearance at that point!

Alternatively you could have the bearings shimmed correctly and put a 1/2 spacer between the hub flange and the brake drum and the bearings would still be shimmed correctly

 

[Magnetoman]

No sir, I'm afraid not.

Well, one of us has to be wrong. The way I see it is if there is clearance to allow the bearing to move back and forth (i.e. end float), if instead the bearing were fixed in position, there is the same clearance to allow the outer race, and hence the drum, to move back and forth.

 

[Robert Watson]

The outer race is fixed in the hub and is fitted with the taper narrow end in and wide end out. The cone is fitted to match and the inner race of the cone goes against the shoulder on the hollow axle. The whole plot is assembled (both sides) and then the correct end float obtained by shimming between the inner race and the shoulder on the hollow axle. The drums are fixed firmly to the flanges on the hub. The distance between them does not change. The only change occurs with the addition or removal of shims behind the bearings which will move the distance the backing plates are from the drums. When all is done correctly there is a very few thou end float, and I will concede that this does allow some movement.

The drums do not move relative to the outer races.
The drums, hubs, spoke flanges, can move as a unit relative the the backing plates, inner races and hollow axle by the amount of end float. If this .005 (recommended by Richardson which I use as an upper limit) is the movement to which you refer, then you are correct for the inner race and I am correct for the outer race!

I see now you have corrected your previous post to "inner race"

 

[timetraveller]

MM Robert is correct in this and when you have got further into your dismantling you will understand why There is also the matter of the shape of the bolts which hold the brake drums on to the hollow axles, spoke flanges, etc. There are two types of these but when and where the change was made I do not know. There is the type described by Robert with the offset cylindrical heads which are constrained from turning by the interference between the bolt heads and the bearing housing. The other type had a hexagonal head with one flat cut lower than the other five. That undercut flat sits against the bearing housing. Both types work well.