Recent Posts

Pages: 1 ... 3 4 [5] 6 7 ... 10
41
British Bikes / My 1951 G2 Trials
« Last post by murdo on June 07, 2026, 08:12:49 AM »
Have taken on the resarrection of a 350 Royal Enfield and has been robbed of most of the engine case nuts. Has anybody got any suggestion as to where to get nuts from in Australia for a reasonable price? Thanks.
42
British Bikes / Re: Matchless overhead cam parts
« Last post by cardan on June 07, 2026, 07:50:42 AM »
Thanks for persevering! Very interesting.

It's a funny engine, depending on how you look at it either advanced (ohc) or primitive (oiling and other stuff). Somehow the the presence of a set of timing gears to get up to the back of the engine, but still needing a magneto chain from there, seems a bit weird. But interesting none-the-less.

Do you know anyone who needs the engine parts - they're probably available.

Leon
43
British Bikes / Re: Matchless overhead cam parts
« Last post by 33d6 on June 06, 2026, 08:30:09 AM »
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.   
44
British Bikes / Re: Matchless overhead cam parts
« Last post by 33d6 on June 06, 2026, 06:03:37 AM »
I replied to this but my reply seems to have gone missing. I know these engines quite well. I'll hang on and see if my answer pops up otherwise I'll have to type it all out again which I don't want to do if I can avoid it. Watch this space!!! 
45
British Bikes / Re: Matchless overhead cam parts
« Last post by cardan on June 06, 2026, 03:11:00 AM »
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
46
British Bikes / Re: Matchless overhead cam parts
« Last post by R on June 06, 2026, 12:09:12 AM »
Oooo Aaaah, a rare bird indeed !
It looks a little incomplete to even contemplate - unless you already have most of one !

That engine must be almost unique in having that head 'sideways' like that ?
Wonder if cooling is better that way ??
47
British Bikes / Matchless overhead cam parts
« Last post by cardan on June 05, 2026, 01:51:07 PM »
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
48
British Bikes / Re: Tiger cub valve timing.
« Last post by cardan on June 03, 2026, 10:00:21 AM »
Brilliant. Enjoy.

Leon
49
British Bikes / Re: Tiger cub valve timing.
« Last post by Vreagh on June 02, 2026, 07:39:38 PM »
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
50
British Bikes / Re: Troubleshooting a JAP Special
« Last post by Rockburner on May 29, 2026, 09:03:36 PM »
The Amal parts arrived today, so I snuck out into the workshop again! :D

Gaskets, float bowl, stainless allen screws, stay-up kit, and a nice mesh "trumpet"


So I started assembling the thing.

The "stay-up" kit is mostly material changes: the float is a military spec material that won't sink, and the mounting tangs are steel (the original part is entirely plastic), so you can easily adjust the float height just by tweaking the tang (phnar!).  The float needle is Viton tipped.


I was also going through all my Amal stuff, tidying it up and separating it out into relevant groups.  I decided to pack up all the Monobloc stuff into a box to be put into store.  I also had a load of random jets and needles from other carb types, so I put those safely away too.


The banjo from the Concentric was a tap rusty, so it got a good brassing.



The single feed fitting from the Monobloc fits the Concentric just fine, so I didn't need to buy another.



I have quite a few main jets.....


230 - 310, and a couple of outliers (140, 360).  I've decided to start with a 260 in the Concentric so I can then work up or down.


Mostly there:


Unfortunately it turns out the sodding needle clip is knackered - it's actually broken across the important bit, so I need to order a new one.
You can "just" make out the break.



So I then turned back to the investigation of the timing chest.

First I dropped the push rods out.


The idea being that I can see if the noise happens without any interference from the valve springs.
Like this I can hold the rod in place to provide "some" resistance.



Being a numpty, I accidentally undid that blanking bolt in the timing chest cover, DAGNABBIT!


Bloomin' thing.


So - to make it a little more secure, I added a springwasher


My investigations were pretty low in results tbh, I still can't quite figure it out, but the old exhaust side cam follower IS a little loose on the spindle, and the roller wheel IS a little loose on it's bushing.... so I may just have to bite the bullet and get another one.  Whether that slackness is enought to cause the clicking noise, I'm not sure, but its certainly a slackness that shouldn't be there.  It could be that with the valve spring resistance, it's causing movement of the cam follower that is making the clack noises.

There was a concern that the spindle itself might be worn, but the new cam follower seems solid on the spindle, so I think that's ok.

I also took some measurements of the push rods so I can look into buying some stainless tubeing to make new ones.
[/url]IMG_20260529_191941_407 by James Bridge-Butler, on Flickr



I think 1/32" wall thickness (info supplied from the Guru, who had a pair without caps fitted) is a mite thin, so I may try to get slightly thicker tubing if available.

The push rod ends are soldered on, so that's going to be a fun job swapping them over... yet more opportunity for conflagations!

Next time I try the timing chest I'm going to dribble some oil onto the cam follower spindle and the rest of the area, it could be that a layer of R is all it needs?
Pages: 1 ... 3 4 [5] 6 7 ... 10