Following the initial assessment, there were a few niggles left to sort out, before taking the bike on the road.

Dunlop K70 Tyres

Dunlop K70s ready to fit

These arrived from Feked complete with two Michelin AirStop inner tubes, whereupon they were taken to Johnny at Value Tread in Hexham. He removed the race tyres and tubes, then fitted the new tubes and tyres, before balancing the front wheel. The original tyres will be re-homed and the tubes kept as spares.

Here’s a photo of them on the wheels and ready to go back on.

This is the first time I’ve used this model of tyre, so it will be interesting to see how they work out. As I mentioned before, I felt the Avon Roadriders were simply too large…specifically the rear tyre. The original Avon Speedmaster and Safety Mileage II tyres have long been superseded as tyres for faster classic bikes.

The Speedo Cable got chewed

When I got the bike, the centre stand didn’t spring back all the way and the original owner’s son warned me I might have to just nudge it up with my foot; this, I have been duly doing.

Speedo cable damage

However, in order to change the tyres, I needed to pop the bike on my rolling hydraulic centre lift; this goes under the engine and gearbox so the bike can be raised off the ground. I did this and never gave it a second thought.

Once the wheels came back, I refitted them with the help of a neighbour to hold the front of the bike whilst I released the safety cam and lowered the bike off the rolling centre lift. I then put the bike on its centre stand and fitted the front brake cable and speedo cable to the rear mounted speedo drive gearbox. I turned the back wheel and heard a ‘twang’, knowing in that instant, exactly what had happened…but not why.

Once I took the speedo cable off the gearbox again, I could tease the end part of the cable out of the box. I then removed the speedo cable from the bike, which revealed the original problem of the cable causing the centre stand to catch (1) and the point where the speedo cable had been jammed and chewed at (2), ruining the cable.

Speedo Cable H12-2/552

The only option was to order a new one; from the Norton Owners’ Club Shop in this case. This speedo cable runs from a standard speedo drive, to an original Smiths Chronometric Speedometer, and is 65″ long; a special cable for the 1954 model year it seems. The one that came from the club was Made in the UK and a couple of inches longer, which isn’t an issue.

The problem had been caused because the speedo cable had been incorrectly routed initially. I’ll check it carefully myself and the extra couple of inches could make all the difference 😉

There are several part numbers for this cable, and they are 19367, NM19367 and H12-2/552. I got the last one the owners club had in stock. I’m sure Andover Norton or RGM Norton will have such a cable though. I wanted to try the owners club spares service and I found it excellent.

I’m left with two issues now:

  • The Lucas Altette horn sounds as if it has been struck down by COVID; hopefully a simple adjustment.
  • The bike has an Amal 10TT9 carburretor fitted. These have no idle facility and are consequently easy to stall. I don’t want to drill a small hole in the throttle slide, so if it’s not good to use on the road, I’ll remove the 10TT9 and install a new Amal Concentric, whilst keeping the 10TT9 safely away in a box.