Exhaust Notes: November 2009

In Steve's words:

"Hazel keeps on mentioning her B25SS/B40 so here’s the story so far of my B25SS. The bike belonged to the son of a friend of mine and he used to go to work on it. One day it broke down and people at work (Foley Motorcycles in Stoke if you know them) diagnosed the need for a re-bore. The engine was part stripped and the barrel sent to “a friend who does these things”. The owner then rode a Japanese bike. He was unfortunately involved in an accident and didn’t survive. The BSA sat in dad’s shed for four years reminding him of the lost son. He eventually decided that he had to sell the bike but felt that it should at least be in a running state. On trying to retrieve the barrel from the “friend” he was informed that it had been lost!

At this stage I became involved. My friend knew that I had BSA‘s and asked for help in getting the bike running. We managed to buy a replacement barrel (still on standard bore, and not in need of a re-bore) and a new, standard piston. We started to put the engine back together but did not manage to complete the job before winter. After winter was over my friend phoned me up and told me to bring my trailer round to his house, he was giving me the bike! This I did.

When I got the bike home I started investigating things further. I knew that there was no oil filter in the return line and, following discussions with various dealers, I was told that filters usually fitted to a Norton Commando would suffice. Needless to say, having acquired one with spare filter elements, it would not fit directly. A bracket was needed to allow the element to clear the swinging arm! I then turned to the electrics. There were no indicators, no large capacitor for running without a battery (but who needs that?) incorrect switchgear on the handlebars, and the wiring was frightening! I obtained proper wiring and connectors and re – did the wiring. With the engine in place but no oil pipes I could not properly try anything but I could move the kick start lever by hand which points to other possible problems. One or two friends on my estate suggested that I had a word with someone who lives round the corner from me and who has restored bikes for others in the area. I went to see him and asked for, at least, some advice. He no longer does restorations but said to take the engine to him, we (he) could strip it down whilst I was there and he would pass judgement. The due day dawned and, having taken the engine out of the frame and the head and barrel off, I took it to him. Before stripping he looked at the barrel (apparently ok although needing a hone), and also the piston which matched the barrel. As far as he could see the head and valves seemed ok but that would need to be stripped to give a proper decision. The next part to come under scrutiny was the big end! This was good and properly shot (not his words but I wouldn’t put them in print). On further stripping down, the shells (-20 thou) were wrecked, the crank shaft needed a re – grind and the con rod was scrap! A local firm has managed to turn the crank shaft to -30 thou, Autocycle Engineering have produced some new, -30 thou, shells, and they’ve also come up with a brand new Daytona con rod which should fit.

This is the current state of play with the engine; I’ve got other jobs to do before it will be on the road (hopefully next season).

To Be Continued………"

Steve