-JdK- I have had this bike since 2007. Bought from Mark Upham in Austria who got it from the UK. It's a 1929 Model 18. Correct for 1929 are frame, engine, gearbox, rearwheel, oiltank. Petroltank is probably from a CS1. Frontwheel is probably Webb (but has a much better brake than the original). Girders are Norton International (much sough after). Correct front hubs and girders still pop up on eBay. Correct primary chain case is available and comes with the bike (below).
It has been used for amateur racing in the past. Click this link. The engine has been tuned by an expert. The flywheels have been polished and skimmed and run extremely smooth. It has a slipper piston and larger size inlet valve. The cams are probably remodeled or IT racing cams. It runs on Castrol R40.
Simon remembers the bike from the past: "I am pretty sure this bike is one put together by the Lewis Bros back in the late sixties or thereabouts for racing purposes and they even lent it to me at one Crystal Palace event when the New Imp I was down to ride misbehaved. The engine fitted at the time was one of Stan Johnson's and had plenty of urge but I thought the steering was awful as the fork dampers were done up too tight. No time to discover this as I did not practise on the bike before the actual event. If I recall correctly it has the little plunger device fitted to help with gear changes (not missing second gear) and it also had a CS1 tank fitted which needed extra height rubbers to clear the top frame tube."
Gearbox has been rebuilt 50 miles ago after it broke a tooth from the sleeve gear; this has been replaced by a good used one when the complex main bearing was also rebuilt and a new bronze mainshaft bearing made. Both chains were also replaced 50 miles ago. The non-pos box works very well and can be operated by foot.
Magneto was rewound 5 years ago; carb is a new Amal 276. Wheelbearing rear (Enfield) has a nice tapered bearing in good shape. Frontwheel has new modern bearings.
Paint looks very scruffy which suits the bike well. There's no rust. Petrol tank has a dent, has been sealed, does not leak.
The bike goes very well. Click the video above to see it running. Gearing is long, it needs clutch slip for takeoff but very pleasant once on the go. 2nd gear can be used till 80 km/h. It has been clocked using satnav at 120 real km/h and is faster than many end-1930s 500cc bikes. Can be used as is.
Numbers checked by VMCC see below. Engine is from a 1929 Model 18 shipped to Egremont. Frame number could not be found; the reason is that the works records are organized by engine number and frame numbers are quite random so very difficult to find. These frames were however unique for 1929 so it must be 1929.
It still has some UK paperwork, see the MOT form below that lists the frame numbers (S38886) and the UK registration number (SV8848) which is a Kinross County Council (Eastern Scotland) issued number.