Pieces

According to an expert, the frame is from a Monark 1929 350sv. 

As it happens I have a sutable engine (should have been a Blackburn), a JAP 350sv from 1929, featured in another post in this blog. I also have got a 1929-ish Albion 3 speed gearbox (should have been a Burman) that also fits the frame.

Featured in the picture is a Husqvarna 250 1929 oil tank. Got it cheap, did not know why, not before I started looking for an oil cap.  Had to buy a new replica oil cap and thar was not that cheap.

Rear wheel has now got a NOS Trelleborg Trial tire.

The seat is a rear seat from an unknown bike. But in wery good condition and from the same manufacturer that made seats for Monark, Husqvarna, Rex an other Swedish motorcycles at the time.

Slow but steady progress, not.

Magneto

In my quest for sparks I have started piling up useful things. Junk might be a better word.

Todays visit to a swapmeet got me a SEM magneto and a brand new 18mm Lodge spark plug that might be useful for the 350cc engine.

Yesterdays swapmeet got me a brand new ignition coil, that might fit the Wico magneto that came with the 600cc engine.

The used coil at the bottom..

At last weeks swapmeet I got me a pile of used and new spark plugs for both engines.

Carb

I'm not sure the carb can be fixed. It's heavily corroded and I suspect the main jet can't be dismantled without destoying the threads or something worse.

Cheap fix

Since the Mark III engine was stuck, my fear was that the cylinder had been flooded with water and was a complete rust-disaster. At least the air filter was full of water...

Guess what, the rust was not that bad even if it is very worn and has some damages, it probably could be made to work. Only had to spray with penetrating oil and wait a couple of minutes to free the piston.

After some light grinding with 400 grit wet sand paper soaked with WD-40 (oil), the damages are clearly visible.

Annealed copper cylinder head gasket lightly sanded.

Amal 225/3

The carb for the Mark III is like no Amal I've seen before.
Wonder if it's possible to get spares if needed?
At least a visual inspection shows that the tickler is missing.

Newsflash

Got me another JAP engine project too as well as the Howard GEM Rotavator ( rototiller) it is attached to. The engine is a 600cc s.v. Mark III Type 5

Engine number is:
UCZ/Z
94433\5

If I'm correct that would be:
U = 600cc Side Valve Engine, 85.7 x 104mm bore and stroke
C = Sports Engine
Z = Dry sump Lubrication
Z = 1933 Model Year

U is a standrd 6hp (4½ hp nominal) engine, according to The JAP book so what with the C marking?

The JAP Engine Reference there are more alternatives and the Mark III engine is recognized as a Sports engine.

My hopes were that I could get it started. By lubricating with the famous Omega Omicron  636 penetrating oil. So far I have got the valve lifter, throttle and most other leavers and functions to work.

Unfortunately the next step is to dismantle the cylinder head to see how bad the cylinder and piston is since the engine is stuck.

How it all started

For many years I've been drooling over pictures of old Board Track Racers as well as I allways wanted an old side valve engine to fondle with. Of cause there are a couple of them that I can pay a visit to at the local MC Collection whenever I want. That's just not the same.

The other week I was going through adds on the eBay and found this restoration project. An old JAP 250cc S V engine.

It was missing a lot of expensive parts as the Carb, the Magneto and the Oil Pump but I took a gamble that at least the internals would be possible to salvage and bought it more expensive than first planned, but what the heck.

When I later was scanning the internet for a parts list I stumbled over Trevor Hall's 600cc NUT Board Track Racer. From there on it was just to hang on and "go with the flow"

Rest of the few pictures of it can be found here.

The intention is NOT to build a replica of the above pictured racer. It is going to be my personal interpretation of a Board Track Racer, that will hopefully look a bit like the NUT