Charlie's Shed - recovering threads

 OK, so this is a commonly available AJS/Matchless frame stud, used under the seat nose to unite the front and rear frames. I can get a replacement very easily if I want to, but what if it's a unique part? 

The object of this blog post is to illustrate how to recover a part like this in the workshop. This stud has obviously been loose at some point in its life as the thread is worn away beneath the frame tubes where the rear frame fits over the stud.

Start by stripping it out and cleaning it on the wire wheel. We are going to be welding some overlay into that worn area and we don't want anything contaminating the weld. When you have it clean, use a thread gauge and a micrometer to make sure of the pitch and diameter - it's quite easy to mix up thread pitches, and you will even get the wrong nut on a thread for a few turns: something you don't want to do with a thread cutting die.

It would be nice if we had some sort of facility for rotating parts like this whilst welding, but if you work towards yourself it is quite easy to do a quarter or a third of the diameter at a time: 

A few minutes on the lathe reduces the welding to a plain shank suitable for thread cutting. Since there's a little bit of the original thread remaining on the stud, it's easy to start the die to recut the thread.

A few minutes later and the stud is good as new.

AJS Model 30 - swinging arm spindle

 Tom gave me the AJS swinging arm spindle to look at - it's had an engagement with Mjollnir or one of his brethren at some stage and will not enter the bushes.

The micrometer shows the diameter of the shaft at the damaged end is around 1.005", up from the 1.000" specified diameter. The areas where the bushes bear are around 0.998".

It's far too hard to turn, even using a carbide tool, so I have set up the tool post grinder to repair it.

I've added a small chamfer at the damaged end.

Next step is to send it home for testing.

Charlie's Shed - USB charging port

 Lately I have been using my Beeline motorcycle sat nav which I won in a competition (Do you remember I told you about it a while ago?) and I have been worrying that it will flatten my phone batteries - consequently I've decided to fit the same USB charger as I have on the W/NG to the Huntmaster.

I buy these from eBay for about £15 - they are very nicely made.

The eBay description says:

• Square Dual USB Super Fast Charge + Voltmeter
• Input voltage: DC12V
• Monitorable voltage range: 6-30V
• Product material: ABS high and low temperature resistant flame retardant environmental protection material
• Qualcomm 3.0 quick charging standard
• Output voltage: 5V3.4A/9V2.5A /12V2A

I found that they seem to work perfectly well coupled to a six volt battery because of course I'm only looking for a five volt output from the USB ports. The voltmeter is quite useful if you can actually see it - but you use it for diagnostics not when you are riding your bike!

You have the option to fit these things with a bracket or a handlebar clip and they come with a length of cable and a fuse holder.

I wanted to fit the charger inside my left knee above the battery and in front of the toolbox and I made a stainless steel bracket to bolt underneath the dynamo regulator.

As you can see in the picture it's too low and you can't get the battery back in. I might modify this bracket or make a new one to give it higher and further in board to allow it to stay in this position:

Nevertheless I can wire it up and show it working:

Until I get around to making another bracket, for which I really need to remove either the seat or the toolbox or both, I will use the handlebar mount and fit the charger above the Monimoto, behind the toolbox.

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:

AJS Model 30 - a new bike joins the family

 Well, his has been a long time coming. A few months ago, son Thomas & I conceived a plan to buy a project we could build together with the kids - to give them some hands on experience and learn some new skills. I wanted Tom to buy something he really wanted, and we looked and bid on a Sunbeam S7, a BSA B50, an A65 and looked at an Ariel NH (which was a very good deal but wasn't a project).

I'm delighted that we ended up with this, a 1958 AJS Model 30 - Tom says there is a poetical symmetry to it, since I had a 1957 example when I was at university which we sold soon after we bought our first house.

It's an eBay find, described like this:

• AJS Model 30 Project rebuild or spares.
• Frame and engine are 1958 model 30
• Was going to rebuild, but will never happen, so must go.
• Engine fully rebuilt by local AJS Model 30 club specialists 15 years ago, still turns over fine. Comes with AMC gearbox and clutch etc. and majority of all major parts to rebuild, look at photo and you’ll see what’s included.

Obvious things that are missing are the silencers, mudguards, speedo and rear shocks but if we really have a properly rebuilt engine for less than £900 we will have done well!

Main frame and wheels above and most of the rest of the cycle parts below. Siamese exhausts - a sidecar bike? The rear mudguard stay looks like one from the CS model; there's a chainguard, brake pedal, battery carrier and lots of other bits:

A box of bits, including a new looking set of engine bolts:

Another view of the same curtain - there are two tanks in the kit that arrived and we see fork legs, some very high bars, a set of yokes (one of two), headlamp shrouds, one of two headlamp shells, centre stand, a head steady, footrests, frame rails, sidestand, oil pipes, engine plates and covers and the toolbox:

A tidy 58/30 engine with dynamo, gearbox, oil tank, primaries and clutch:

We can't wait to get stuck in!

FH - update

 The FH has been the go-to bike recently, and it is shaking down again after it's 500 mile service. I'm getting on top of the carburation helped by Hitchcock's (or Amal's?) guide to tuning the Mk1 Concentric, and now that I have it ticking over with a #30 pilot jet and the pilot air screw 1/4 turn out, I might go to a #25!

It's flying along and looks great:

Notice that the rear wheel is nicely off the ground in these pictures!

The only problem is - it's still burning oil in little puffs on start-up or when taking off from a stop, not constantly. The head is going to have to come off again to inspect the guides which is a shame, because the leaks are cured...