AJS Model 30 - the 'what bits are missing' dry build

 A few days after the Model 30 kit arrived in Norfolk, it's outside in the street for a degreasing session which will help us understand what we have, what we don't have and how it goes together.

The main frame parts are all there and most of the big studs as well.

Some of them are not in great shape and will need replacing or building up with weld and the threads recutting. And option would be to buy a complete new set at vast expense but we are not there yet!

The centre stand, it's bushes, stud and spacer are all there:

Footrest bars, footrests and side stand are also there as is the spindle for the swinging arm – but the cotter pins appear to be missing:

We have two sets of fork yokes but unfortunately the steering head races are a bit worn. We will see if they need replacing later on:

FH - Preparing for assembly

 One of the nice things that arise from a dedication to one make, one era or perhaps just motorcycles manufactured in one country is a collection of specialist tools. Today, I'm quietly cleaning paint out of the threaded holes in the frame, yokes and swinging arm with CEI taps, while I wait for other bits to arrive and for the rest of the painting to be finished:

The fork stanchions have arrived:

And we have new seal holders, seals and progressive fork springs:

FH - swinging arm trick

 Ariel PRF frames have a close fitting swinging arm that looks like it comes out backwards.

It doesn't, because the curve of the frame tube gets in the way:

The trick is to push it forward - this obviously only works if the chain guard and oil filter, and the rear mudguard, are already removed. 

Model A - repairing threads

It's a wet day here in Norfolk, and I have some domestic stuff to do in the workshop so while I'm at it I might get distracted...

I'm looking at the workshop layout with a view to getting a bike lift in there, so I have shuffled them around and the Model A happens to be accessible, so we will have a look at a couple of loose ends. The front mudguard has been hanging off for a while (and still is) because there are a couple of dubious threads in the forks - one, a broken bolt, and then two other threads that are just fouled.

Here's the broken one - I have put a 1/8" hole through this broken 1/4" bolt, to see if it will come out with an Easy-Out. They never do, but I have to drill the hole anyway!

Of course, it didn't come out and I moved through the drills until I was one size under tapping size for 1/4" CEI. I then applied the 1/4" CEI taper tap and used it to clear the thread - it moved the remains of the bolt:

Next stop, same problem at the back. I made the mudguard & rack fasteners a while ago and could only fit one side, because I found someone had broken one of the 3/8" bolts in the frame lug, drilled and tapped it something like 5/16" and put a new bolt in. Today, I removed the broken 3/8" stump using a diamond burr in the Dremel and chasing out with a 3/8" CEI taper tap, so this shot shows it all back together with the stand spring fitted at last:

I also took the opportunity to chase out the chain adjuster threads. Grovelling about on the floor makes me realise that a hydraulic lift would be a nice addition to the workshop!

Back at the front, I now have both sides of the mudguard stay fitted - to cut the mudguard, I need the centre bracket and the front stand fitting - unfortunately I have run out of 5/16" screws, so that's the next job.

Comparing the next picture with my picture above, you can see I have the mudguard stay too far forward:

QR50 - Frame: can't see the wood for the trees

Something has bugged me about this bike for a while, something I couldn't quite put my finger on. It started with a Honda publicity picture showing an exciting red dirt bike, typical of their 80's dirt bikes, and a dirty old relic in an ebay picture which strangely gave no hint of Honda's magic.

One day, fitting the silencer and trying to determine the right position relative to the frame and engine I saw what I had been missing. Take a look:

I had been using this picture to scale the size of the silencer:

Seeing it for the first time, I realised why the seat didn't fit properly and how the rear wheel had come to wear a hole in the mudguard. It took half an hour to get the bike off the bench, lift the frame off the engine and remove the forks. 

I put the frame in the vice, holding the rear frame loop on one side and applied some heat - the frame soon moved, and I flipped it over to bend the other side. I made the bends gradually, turning the frame each time so that I could be sure that the bends were going in the right place and that I did not overdo it. 

The seat now fits properly, with the rear bolt holes aligned with the frame lug. 

QR50 - Assembly

It's a grand time in any project - where you are casting around for jobs and realise there is little left to do on the components. I'm at that place now with the QR50 - the crankcases are closed up, the frame is painted, the forks are done, the shock absorber is done, the centre stand is done and most of the transmission components are ready.

Right now, I can't start the wiring; I can't assemble the generator, the oil pump or the carburetter, I can't look at the exhaust or the generator cover, both of which are significant fabrication activities. What I need to enable these jobs is to put the main elements of the bike together.

Here we go.

First job is to prepare the transmission. The nut shown at 8 o'clock is the fulcrum pin for the rear brake shoes - this is inaccessible when the transmission is assembled:

Here's the fulcrum pin in position:

Next is the output shaft, with a bit of oil to lubricate the oil seal. The bearing is sealed and doesn't need separate lubrication:

And from the other side:

The crankcase is together, and this bracket bolts underneath to carry the centre stand and the rear shock absorber:

We can then fit the main frame spine and sub-frame on top of the crankcases:

The single shock absorber bolts in next:

Here's the other side:

I've fitted the barrel and cylinder head, to get a feeling for the space they occupy:

The inlet tract and reed valves are on place as well. Stepping back:

This is the oil pump drive fitted, which brings us to a close for the moment. The oil pump needs painting and some oil lines adding; I can see the routes and lengths of the harness now and once I have painted the transmission cover and finished the kickstart shaft I can assemble the transmission.

QR50 - Fork Bushes

As you know, I have decided to make a new set of telescopic forks for the QR50 since I can't find a new pair locally, or anywhere else for that matter, for a reasonable price. You've seen how I recovered the sliders and stanchions with new tube, and replaced the missing dust caps with machined parts.

Now it's time to machine the bushes and assemble the bits. I bought a 30 cm length of 30 mm white acetal, and cut off two 80 mm lengths, planning to make a complete leg-set of bushes in one setting. I wanted to make sure the set-up for the 22 mm bore was done without removing the material from the chuck.

I made a drawing to set my bush lengths against the existing design and the springs I had bought:

I set one of the 80 mm lengths up in the 3-jaw and centre drilled it, opening it up through 6, 10, 13  and 19 mm for the boring bar.

Here's the boring bar in action, taking out a 40-45 mm length to 22 mm or so to give a sliding fit on the stanchion.

From this bored part, I finished the top bush OD to 29 mm and parted off.

The top bushes fit in a 29 mm ID register in the slider, which is made from 32 mm OD seamless tube of 2 mm WT. The bush has a 0.5 x 0.5 mm register in one end to let it sit just below a circlip groove in the slider.

The circlips are wire type - I bought the sheet metal type initially before I realised there wasn't sufficient space in the leg to house them. Wire types are harder to get out but occupy much less space. The nominal 30 mm circlips need the ends trimming:

The clips fit in the end of the slider nicely - there is a 0.5 mm deep groove about 8 mm in, to let the clip retain the top bush:

The slider has a ground channel to allow you to get a scriber under the circlip:

It's very hard to see, but the circlip ends are ground flat to allow you to lift the ends out of the grooves:

The bottom bush is essentially a blind tube - bored 22 mm for the stanchion and finished to 28 mm OD for the slider, it has a 5 mm thick closed end to seat the spring. It's loosely retained to the stanchion with a small roll pin.

This shows the complete assembly, with the dust cap, main compression spring and the rebound spring. The springs were bought from ebay, selected for wire diameter and OD.

Here's the stanchion in paint:

The frame is also almost finished:

By the way. This interesting effect is called fisheye, and is what happens if you don't degrease the parts prior to painting...

QR50 - Turning a corner

I've spent most of my time recently cleaning up mucky QR50 bits and yesterday evening was no exception. I had a few hours spare and a new set of wire brushes from MachineMart:

I set these up in my flexible drive and attached it to the pillar drill, and with the frame in the vice took all the paint off. The set is quite useful in that there are several sizes to get in all the nooks and crannies:

The big wheel deals with most of it. This is much easier than using a wire brush in the angle grinder, but less easy than the bench grinder. Horses for courses.

Two and a half hours later and the main frame spine is done:

Before I painted it, I straightened out the damage to the oil filler neck:

I used a piece of 22 mm bar, the gas torch and a 17 mm socket to get this round again. I have to make a cap to fit in the hole...

It took more time to shake the rattle can than to get some primer on the frame. In this marine environment, it doesn't take long for rust to set in: