Front Wheel Refurb. Brakes and bearings

The front wheel on this bike was very rusty and the brake was siezed. Good news is that all the parts seem to be there including the speedo drive (not cable), and with a bit of effort the brake lever did move and engage the shoes so there must be something on the inside. On the bad side the speedo drive is very stiff and the chrome on the rim (a feature of this model) is completely unsaveable. 

Stripping

Removing the wheel

Put the bike on its centre stand and remove the front wheel by first detaching the front brake cable... If you are lucky enough to have one that isn't rusted solid that is, and speedo cable. I had no speedo cable and couldn't remove the rusted brake cable and so left it for later. 

Remove spindle nuts from both ends of the wheel spindle

Loosen leading link forward clamp bolts. 

Tap spindle out towards one side of bike. Support the wheel and remove the spindle completely, catch the speedo drive as it comes free. The wheel can now be slipped from between the forks

At this stage I removed the brake arm and spring so I could detach the brake cable and so remove the wheel completely. 

There was a lot of rafia binding packing under the speedometer drive where I'm assuming a seal is missing. The wheel bearings are very rough. 

RHS view with rusted brake arm, note that there is a second nut on this side below the spindle nut which secures the brake plate

LHS loosening the leading link clamp bolt

Unscrew and remove the LHS spindle nut and loosen the leading link clamp bolts both sides before...
Tapping the spindle out to the RHS

In my case I hadn't been able to slacken the brake cable so I had to remove the brake arm in order to disconnect the cable. I forgot to do it, but at this stage it's a really good idea to mark the arm and spindle so you can get them back in the right relative position or you will have trouble refitting and adjusting the cable for correct brake action.

The arm then comes off. Note that there is a wave spring washer (type DIN137 presumably because there isn't room for a normal spring washer) beneath the nut and a return spring behind the arm.

Brake arm components separated

Brake Plate removal

To remove the brake plate/brake shoe assembly you have to remove the retaining centre nut. I used a G clamp to apply the brake so that I could then shock the nut loose with a soft hammer blow and a 22m flat ring spanner.

The brake plate then lifts out, the shoes looked pretty good to me

Inside the brake plate, two shoes present engaged with large U spring

with lots of meat left on them. However the fastening rivets holding the linings are a little rusty so I will probably have to change them for safety reasons.

Brake linings are quite thick still- not so confident in the state of their rivets

Note the shim that sits inside the hub below the brake plate. remove this and keep it safe.

Shim washer beneath brake plate inside drum. Note hollow end plug/bearing  cone through which the spindle passed (now removed). Oil seal is visible

Bearings

This is where the antediluvian design of these wheels catches up with you. They are probably over-engineered by today's standards with  3 part conical thrust bearings in each side.

Assembly of front hub. This diagram is actually for an L bike and shows two possible versions of the central tube arrangement. My bike is pretty much the lower version 5, 9,10,12. This diagram irritatingly uses different numbers for items that appear to be the same (such as oil seals 6 or 13 and bearing cages 7 and 14) but the same numbers for others (like the outer races both numbered "2" above)!

In brief the wheel rotates on a spindle (25) which has now been removed. This spindle crosses the hub inside a tube formed from three parts; There is an end plug each side (11 and 4 or 5) which screws into a central tube (8 or 9). The end plugs also double as the inner race for each bearing and rotate in a bearing cage (7 and 14). This in turn rests in an outer race  (2) tapped into each side of the hub. The hub is packed with grease and this is retained by an oil seal on each side (6 and 13) also retained by the end plugs. Later versions of the bike have an internal crush structure (10) fitted in the central tube... I don't know what this is for?

There is a 15mm flat on the end plugs/bearing cones both sides of the wheel...

15mm flat on end plug LHS, speedo drive unit removed.

Use two spanners to unscrew the  end plugs/bearing cones.

Using two spanners to unscrew the end plugs/bearing cones of the central tube

LHS plug/bearing cone being tapped out from the  other side using a carefully positioned drift. 

This is where the shortfalls in design catch up with you. Each side is screwed into the threaded centre tube so its an even chance which side will unscrew first. Obviously it would be nice if both came undone at once but that's simply not going to happen! Once one side has unscrewed the central tube will then simply rotate with the  remaining plug. There's no way of grabbing this without damaging it and so the remaining plug can't be unscrewed further. In my case the LHS plug unscrewed first leaving the brake side plug still engaged in the central tube. I knocked the now unscrewed LHS plug out using a drift inserted through the hub from the other side and positioned against the end of the plug. Its not held tightly at this stage, only really by the tightness of the oil seal and a grease vacuum seal to the bearing cage inside. As an alternative you could maybe lever it out and avoid risking damage to the threads?
Once the plug was out, the oil seal beneath could be levered out with a screwdriver revealing the bearing cage. This also just lifts out.

LHS oil seal removed, shown on the hub below the opening. The bearing cage is visible inside the hub, it lifts out.

Once the LHS bearing cage has been removed the LHS plug can pass inside the hub. The only way I could find to remove the other (RHS) end plug was to refit the LHS, screwing it well into the central section so that the threads would take the force and then drifting it out through the hub towards the left with a hammer. You could use a separate drift but you need to be careful not to damage the thread starts on the central section or you wont be able to screw the end plugs in on reassembly. This drives the central section out complete with the RHS bearing cage and oil seal all attached to the remaining plug and leaves both outer races still fitted in the hub. I doubt that this is the right way to do it and I am concerned it may have damaged any fit between the inner sleeve and the bearing outer race. Is this tube meant to be able to pass through the race?I will check when it's out and clean but may have to replace the centre tube. The process could have been simplified if some means of holding the  central section had been designed in. Something like a removable plug in the wheel hub so that you could insert a rod through the hub and into the central section to prevent it turning, a central hex plug or even a slot cut through the ends so that whichever side released first  could then be held with a screwdriver whilst its partner is unscrewed. I may make such a modification before refitting.

Central section drifted out. The refitted LHS end plug is shown on the left, the RHS end has been removed with the oil seal and bearing cage

This process leaves the inner races fixed in the hubs. Each can be removed by tapping it downwards with a punch inserted from the opposite side of the hub. Support the hub on blocks or an open vice as you do this so the race can drop free. I think this might have been a better approach to removing the end cap above. Perhaps a carefully positioned drift could slip through the wheel and bear directly on the back of the outer race. This could then be driven out, pushing the bearing cage end plug/inner race and oil seal and dragging the central tube all at the same time. This would have avoided the potential for driving the central tube into the bearing cage?

Drifting out the inner races, Here a punch is passed through the hub from the top to contact the rear of the lower race which is then tapped downwards to release it from its interference fit in the hub.

I could then clean up the assembly I had removed and  grip the central tube section in the vice (soft jaws) and unscrew the end plug to release the bearing cage and oil seal.

There was obvious wear on the RHS end plug bearing cone so I will replace this, the LHS was fine. I should add that there is a strange collar fitted inside the central section (10 in the diagram above). I suspect its a crush fit between the two end plugs but I don't know what function it serves.

Wear on bearing cone part of the RHS end plug

Speedo Drive

The speedo drive unit turned OK, but it was also a bit crunchy. The grease was hard and solid and I thought it would benefit from a good clean and re-grease. It consists of a spirally cut gear driven by dogs that engage with the hub and turn with it. This is engaged with a worm gear in the cylindrical section of the drive to turn the rotation through 90 degs and drive the speedo cable. There is a grease nipple fitted to the cylindrical section to allow both worm drive and helical gear to be greased.

Speedo drive from the rear. The back of the helical gear plate is upwards, worm drive in cylindrical housing with grease nipple at the bottom

Speedo drive outside view

The helical gear can be gently levered away from the drive unit body-  I'm not sure it should do this, I had expected some form of retainer. Anyway it came off easily and will be held by the spindle unit on reassembly. The drive was full of grease and grit

Helical gear levered away from the speedo body

I removed the grease nipple and cleaned all components in diesel and carb cleaners. Finally I flushed it though with WD40  and set aside before reassembly, I fitted a new grease nipple.

Grease nipple removed

Renovation

Wheel

The wheel turned out to be in far worse condition that I had expected. The tyre bore a Feb 1965 marking and so was clearly beyond its service life. I expect the tube is a similar vintage so both will need to be replaced. I removed them and discovered that the rim tape was also perished. So far this was pretty much anticipated but I wasn't expecting the poor state of the chrome. I had hoped  to chemically remove the rust and if necessary, rub down and paint the rims. In fact the chrome was lifting/lifted in many places, breaking off in viciously sharp flakes revealing pitted steel beneath. I removed what I could with a wire brush and wire wheel but much dodgy chrome remained and it would be pointless painting over it. It may yet transpire that I have to replace the rim (and spokes) for this wheel but in an attempt to rescue the situation (and save some dosh) I took the wheel to be sandblasted in the hope that this would remove all the loose chrome and give me a firm base on which to paint.

Lifting chrome and pitted metal visible on wheel rim.

I tried sanding, but in the end opted to get the rim sandblasted. It came back with most of the chrome still on but nicely keyed. The razor sharp flakes were largely removed but still needed more sanding and wire brushing to smooth this out. 

Sandblasted wheel 

Rim close up

 Sadly they also sand blasted inside the brake drum. Current advice is that this won't matter so I polished it over with fine grit emery 600

 Rim rubbed with Emery, this revealed that much of the chrome was still present. There were a few loose  flakes which I could remove. I'm not particularly happy about the finish but I'm hoping that a combination of rust treatment and filler/primer will give a smoother surface.

Sandblasted rim rubbed with Emery paper

Once smoothed I applied two coats of high build etch primer followed by two coats of Halfords Alloy wheel paint.

Wheel sprayed in High build etch primer

... and in alloy wheel paint.

Paint was followed by two coats of clear lacquer to protect the finish.  

Spokes

Spokes should all be tight- as a simple test they should ring not buzz if you drag a screw drier round the wheel. I found two that were loose. Since these are loose they are presumably not actually holding the rim so I tightened these with a spoke spanner but only to the point where the buzzing  stopped. To tighten any more would risk distorting the rim.

The spokes terminate inside the wheel but as they are tightened the metal rod is pulled through the rim and so projects into the void. I checked the rim for any protruding spoke ends and found one (not one of the spokes I had adjusted). This needed to be filed flat or it will likely puncture the tube when its fitted. Interestingly although the old tube did have one obvious puncture, it wasn't on the internal side and so can't have been caused by this spoke. 

Once the projections were filed flat I could fit a new 19" rim tape. I bought heavy duty off road tapes.

Heavy duty rim tape fitted, aligned on the valve hole.

Brake back plate

I also needed to dismantle the brake plate and clean it up as it was pretty rusty. The shoes are held on by a large U spring which makes it harder to lever the shoes up in a Vee as would be done with conventional springs. 

Brake shoes as fitted

I levered the pin side up and out to give more room

One shoe detached from pivot pin

And I could then move the shoes enough to get the flat ends away from the actuator. One of these rested in an anti-squeal shim. This isn't shown in any of the parts diagrams so I don't know if it's original or not, or for that matter whether there should be one on the other shoe.

Detaching the shoes- note anti squeal shim

I could detach the brake lever, it's m7 half nut and DIN137 wave spring washer beneath. In my case this was cracked and will need replacing

Brake components separated, note anti squeal shim on shoe foot

Anti squeal shim separated

Lever components

The actuator spindle then just pushes through. It was a little rusty but still well greased so I'll clean it up before refitting.

Brake actuator arm removed 

I de-greased and wire brushed everything free of loose rust, and then sprayed the brake back plate in zinc primer. This will be re sprayed to match the wheel although currently I'm worried that the finish might be too "blingey" so may respray in Hammerite to tone it down a bit. I reassembled the brake plates by reversing the disassembly process

Reassembled brake plate- I decided to keep the original linings as once cleaned up there was little evidence of rust on the rivets.

External view

Rebuilding

Bearing Replacement

I received my new parts as below.

Firsts tep is to tap the outer races (cones outward) into the hub. I seated the cones by hand and then tapped them in using either the old  races, or a suitable socket once they have vanished below the hub rim. The races bottom out in the hub with an obvious change in tone when struck,.

The race in the speedo drive side has to be tapped down too.

Fitting the new bearings was a little unusual. I'm used to taper rollers where the usual approach is to fit the inner race, add the outer and slip the assembly onto the hub. You can't do it in this order for the Quickly and probably all three-part bearings. This is because although the end plugs/cones will easily pass through the bearing cages when off the bike, the act of inserting the bearing cage into the outer race pushes the bearings inwards and narrows the central space so that the threaded section of the plug will no longer pass through. Consequently fitting the bearings has to be done in a different order. I presaasemble the brake plate side: Grease up the bearing cage as usual by loading it with general purpose LM2 grease. Assemble the brake plate side by first passing the bearing cone or end plug through the oil seal (grease the lip), then the bearing cage (taper inwards) and finally screw the end plug fully into the central spacer tube (inserting the crushable internal spacer and some grease).

RHS (brake plate side) assembly. This uses the flanged end plug/cone, the oil seal is added first, then the bearing cage ...

... and this is then screwed into the centre spacer section.

This structure can then be passed into the wheel hub.

Assembled plug/cone unit fed into the hub

In the same way assemble the LHS end plug by adding the oil seal and bearing cage, and then pass this through the LHS of the hub, screwing it into the central spacer tube.

You can then use two 15mm spanners to tighten both end plugs into the central spacer. The flange on the RHS end plug will also push the RHS oil seal into place, although the LHS oils seal has to be tapped home separately. I used a socket to pass over the threaded parts of both end plugs and tap directly on the oil seals to ensure that both are seated. Note that the speedo drive side seal must be tapped down below the level of the drive slots cut in the hub rim so that the speedo drive dogs can engage. The bearings need to be centralised and preload adjusted so I tightened both nuts whilst turning the wheel to centralise the bearings. When both nuts were tight the bearings were now loaded excessively and the bearings would no longer turn, I then backed them off and re-tightened until the wheel spun freely without binding. I have to say that the shortcomings of this design still trouble me. When both plugs are screwed in tight the bearings are too compressed to turn, but when backing them off you can't control where the unscrewing motion occurs. This leaves it an open question as to whether its achieved by  unscrewing just one plug (either side) or both. I had assumed that this must matter because the flange on the brake side should be up against the oil seal and the plug on the righthand side determines the distance that the speedo drive is held away from the hub and, If this is too great, then the dogs simply won't engage with the hub slot.

However I did later fit a new speedo drive and realised that this is actually adjustable to compensate for the fitting of the bearing cones.

Refitting the brake plate and speedo drive

I fitted the brake plate, adding the shim/slip washer first

... and then the backplate, securing it with the central nut. I had forgotten to mark the position of the actuating arm on its spindle so I will probably need to adjust that once the wheel is on the bike and the cable fitted.

Although the speedo can't be fitted properly until the wheel is inserted between the forks since its held in position by the fork leg, I could however test fit the speedo drive unit to the LHS to make sure it was going to work...  In my case I found that the speedo drive didn't work! Firstly the drive itself couldn't sit flush onto the hub and secondly the drive dogs were too short to engage with the slots on the hub.

Gap between speedo drive and hub; Drive dogs too short to engage with cut-outs in the hub rim. I am a little worried that the speed drive doesn't seem to be at the right height to engage with the hub, it may be that the end plug should be screwed further into the central spacer tube.- Found out later this is because the old drive is too worn.

Drive dogs seen from the rear were very worn or damaged. I had to straighten these and clean them up before welding short steel extensions onto them and refolding the tags to engage with the wheel.

Checking the parts list showed that there should be a felt washer below the speedo drive to take up this gap. This washer was completely absent when I stripped the bike. I made a new one by punching a 32mm/19mm washer from 4mm gasket felt and this fitted perfectly. However, there was still no way that the drive dogs could engage with the hub because they were too worn so there was no alternative; I had to extend them; I straightened, de-greased and de-rusted the lugs and then welded a short strip of mild steel onto each. I could then refold these strips to engage with the drive slots. I am still  Concerned about the lateral position of the end plugs but I'll try to refit the wheel and see how this works out.

Fitted new tyre (Heidenau) and tube prior to refitting the wheel on the bike.

Front wheel fitted back on the bike without trouble and the speedo drive engaged with the dogs*.

#*I did eventually replace the speedo drive for a new unit, this needed adjustment so please see tyhe separate post on speedometer drive.