I was wondering as to the best way to route the speedo cable on my C15. The problem with it was that, when I bought it the cable was routed alongside the exhaust, resulting in the plastic screening melting
So... I took a look at the seconds C15 which I bought. I was surprised to find that the speedo takeoff there is the other way up, i.e. above the axle. This makes routing the cable much easier as it can go above the engine, but is this right?
Could someone please advise as to what is the correct setup?
Thanks! Ian
I have 2 C15 s , both different routes and i think it will depend upon the length of speedo cable you have.
1 bike goes above the axle in an arc and then down below the swinging arm and under the timing side of the engine and up to the speedo.
The other bikes comes out of the drive , straight forwards under the swinging arm and follows the other route.
But both are inboard and clear of the exhaust and heat damage
Thanks! I have routed the cable inside of the swing arm, but using cable ties to eliminate any risk of it flapping around and catching on the wheel, and then under the sump.
Watching one of Hugh's videos, it looks like his bike has the speed takeoff above the axle, so, maybe, this is how it would have originally been.
Over the years lots of hands have fiddled with our bikes , so do the best with what you have.
Hi,
The parts books show a 'top' fitting for the C15 and B40 with the 'bottom' fitting appearing on the B25.
However, BSA would have gone with what was available at the time.
The C15 and B40 have different speedos to take account of the larger B40 wheel.
Quite a few of the B25s, A50s and A65s had the same rear wheel and tyre size so common speedo drive was probably used. Bikes with 4.00 - 18 tyres rather than 3.50 would have needed a different ratio but I think this was dealt with in the speedo itself.
Dave.