classic motorcycle forum

This may be helpful searching for commercial catalogues or not but our State Library has also improved its website and search function so you can really drill down and hunt out really obscure stuff. Its surprising what they have.
They also give lots of info on where stuff is held elsewhere and occasionally you can access it through their site.
Most old motorcycle stuff is now held off site and may take up to five business days to arrive. This is absolutely no problem as they run a 'click and collect' service. Order what you want from home, they acknowledge the order, then text you when its arrived to look at. They will hold it for five days before returning it to the archives and will hold it longer if you ask. They really make it easy.
As you can gather I'm a big fan. Have a browse.

Like most things there are more survivors than you think but the only local bike I know of is the Shannons bike and I don't know who owns that now. I'm sure someone would be grateful for those remains for spares but I'm no longer the person to ask.
In some ways it wasn't such a hard engine to rebuild. Matchless stuck to the same 69x93 bore and stroke for their 350 engines for near 40 years so a WD G3L piston just dropped in and the same WD G3L conrod was de-engineered backwards to fit. Matchless rarely did clean sheet designs but just steadily beefed parts up to suit later power outputs so for many parts you just have to de beef them and take them back to original. After a while you get to know the early Matchless parts numbering system and can track down many parts used across the range. Sometimes it really pays to specialise in a specific make and know it inside out. Makes life easier.
 

It hasn't appeared. I'll start again.
This engine never did well, I think mainly due to its dismal lubrication system. Introduced in 1923 it ha the same system as its 350 side valve stablemate. Namely a total loss system that merely pumped oil into the engine to just splash around and hopefully oil everything. In this engine, being of ohc operation the oil line entry was up on the cam gear so you got steady drips on to the valve gear before it theoretically dripped down the cam drive at the cylinder rear to the timing gear train and hopefully after that through in to the crankcase where the big end and piston got what was left. Given the pump was driven as usual practice from down on the timing gear you can imagine how long it took before any oil got up to the cam gear and then started its long drip down to the bottom end. Valve guide lubrication to the exposed valves may have happened on the way through but don't hold your breath. 
It wasn't a happy arrangement and Matchless fiddled around with it for years eventually fitting a duplex Pilgrim pump with the top and bottom ends each getting their own feed.
By this time the factory only fitted it as an alternative 'sporting' engine in their 500ccc ohv single Model V series bikes and this is the version sold by Shannons. The engine did not survive the across the range change to dry sump lubrication in 1930 but that year the new 400cc  Silver Arrow was the Matchless pride and joy. Who needed to be reminded of a dud 350 ohc effort.
I know the Shannons bike quite well. I knew both the original gatherer of all the parts and the next owner who finished it. They were good mates. Both gone now. It would be a very interesting bike to own but definitely one to trear cautiously.   

Interesting. I don 't know that I'd be too keen to mix up oil and grease myself but I think I'll look more kindly on that stuff they recommend for vintage car steering boxes and the like. Can't remember what Penrite call it. Thick like grease when cold but quickly liquefies when stirred up. Thixotropic?

Back to Albion boxes. I've just returned from the State Library where I was ploughing through 1931 copies of MotorCycling. The 11/11/31 copy had a paragraph introducing the new "E Junior", a new 3 speed box for featherweights up to 150cc. Weight 12 lbs. internal ratios 1.57 and 2.78 to 1. High gear the usual direct drive 1:1 of course.
Then referred to the the regular 'E' for 200-300cc machines and advised the smallest 2 speed as redeveloped in 1931 was still to be produced.
The new box of course is the good old EJ, probably the most common survivor found today. As the cheapest 3 speed box they made it was calmly fitted by all and sundry to whatever piece of equipment they needed a box for and  absolutely no notice paid to the factories advice it was a featherweight for up to 150cc engines only. It was the cheapest they could buy and who cared if it was ferociously overloaded. Lucky for us it was tougher than the factory thought. Love them.

It’s got a rocking pedal foot change on the other side. Pretty simple with a two speed box. No fancypositive stop arrangement needed. Push down as far as it will go at one end for low gear. Push the other end down as far as it will go for high gear. Let it flap around in the middle for neutral.

Well, two questions.
How many Model ! Excelsior do I have? One on the road and enough parts, frames, forks, tanks etc to build the full set with all engine and gearbox configurations. Over the years I've run the various combinations at one time or another and currently I have the i72cc Sport engine fitted with a 2 speed box. I have the 3 speed box but it isn't much of an improvement as it has the same ratios as the 2 speeder plus a lower first gear. This is only of use on the most desperate of hills. Of little practical value for normal road use. I have the internals of an early Albion 4 speed lightweight box but am still looking for the right casing. That should make things interesting. Hand change of course, got to keep things entertaining. The original plan was to have the full set on the road but other projects plus creaking bones and joints keep getting in the way.

Leon, the box id numbers seem to have have nothing to do with the year of manufacture. Being a proprietary item as with Villiers engines they didn't make annual changes and just kept making them whilst there was a viable market and in some cases seem to have stopped production and started again if sales picked up. I don't know all the subtleties of whether they avoided confusing letters such as O or I.
My info takes us a few steps further forward but there's still a long way to go.