classic motorcycle forum

I like the head - viewed from above, the angle of the inlet and exhaust ports look to give a nice swirl.

The "sideways" nature of things does seem weird, particularly for a vertical single cylinder. But there was precedent in the sporting ohv Douglas twins, beginning with the Sports model in 1920, running through the Dirt Track and into the 1930s. Like the Matchless, all very sideways! Even earlier was the racing Matchless ohv V twins in the 1914 (?) TT, which used an unusual MAG (Motosacoche) twin with sideways heads. I wonder if the Matchless designers had one of these engines in mind when they began work on the LR in the early 1920s.

The missing bits - particularly all the top end of the valve gear - is certainly a problem, but it's the sort of thing that lurks in sheds as a curiosity, interesting but useless!

Leon

Here's some unusual bits: lumps of a 1920s overhead cam Matchless single, engine number L/R 1618

I don't think I know of a complete survivor in Australia, so I guess they're a bit rare? Or perhaps I don't know much about Matchlesses! Any interest?

(Edit: OK, there is at least one! https://club.shannons.com.au/club/bike-news/old-bikes/matchless-lr2-a-rare-beast/ )

Leon

Well I can now easily kickstart the Cub but may have overdone the lowered compression a little. It start easy and ticks over like a traction engine. Out of curiosity I bought a compression tester to check and it gets to 20 psi which I think is a ratio of roughly 1.5:1 by my suspect reckoning.  I don't  care, it gets me mobile and on two wheels again while I build strength back in my legs. Thanks for all your comments chaps. Keith

Just a suggestion for the click-clack.
I've noticed it on singles when they're being turned over slowly by hand that as it goes over the tip of the cam, the follower slaps down on the flank of the cam under valve spring pressure.
The days before quietening ramps and all that.

Yes - I am starting to think that may well be the cause, or at least part of the cause.

Decided to do today's write up while it's all still fresh.
Lots done today.

Priority was finishing off the Timing chest, so the first thing was a dry-assembly of the Timing chest including all the bits and the gasket;


Which seemed to be going well, until I spun the engine over and realised there was as distinct "click-clak" noise coming from "somewhere"...

ffs.

https://youtu.be/Gza5SEe7pGM

thankfully it wasn't coming from the crankcase....

https://youtu.be/UYPMI_8R3kQ

Primary suspect is the new inlet cam follower possibly clashing against something.

https://youtu.be/qz900MeY3sI

Here's a comparison of the old and new cam followers:


Not much of a difference visible there.. however:
The new one, left is significantly thicker than the old one....


There's also a touch more meat around the pin that holds the metal wheel.



So I tried the old cam follower (which is very, very tired)


I'm still getting the click-clak noises... they're just a touch quieter...

I also reassembled the cam followers with the extra spacer shim at the inboard end of the spindle they sit on, and weirdly I think it's helped a little.

I "think" the new follower IS clashing with the boss cast into the cases that supports the camwheel.  But I think putting the shim at the end is moving it enough to clear the boss, and (weirdly) actually putting the follower more central on the cam "path".

We'll see - I need to play with it some more.  I had a nice chat with the Guru, who was quite puzzled although he has had a similar experience in the past (at least it's not just me!)

We chatted about a few other things including the push rods and stuff.

Then I got on with the other thing on my mind: the Concentric carb.

I split it down for a clean:


BZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZZT



While that was threatening the fuses I fitted the two lower casing covers.
This is the oil "outlet" fitting being prepped.
The Threebond is a nightmare, the tube has now got several holes in, and it's still runny as hell.



Messy


In the end I just poured the Threebond onto the newspaper and spread it thinkly with my finger!



Next, I pulled down an old G-clamp I'd liberated from Dad's workshop, I want it for a specific job and it needs some modifying...



THIS is what I want the clamp for:


To fit the push-rod tubes you have to hoik the push rods out from under the rocker arms, but there's not enough clearance, even with the adjuster wound right off.
With the clamp I can pull the arm up against the valve spring resistance and pull out the push rods.

So, happy with that.

I then progressed to the carb again.

Murky waters....


I messed around for a while fitting the carb top to the control cables: the springs on it are seriously strong, and this nerve issue I currently have has weakened my left hand enough to make things like that problematic. (I'm actually having trouble typing this...)

It's a good thing I had a cathartic session of ordering bits yesterday....


Chrome is for trailer-queens.

I bet the guy sold the carb because he couldn't get it to stop leaking.... Oh well - no matter, new Premier style float-chamber is en route already, along with a few more AMAL goodies.


So - next session will be trying to get to the bottom of the click-clak!