PROJECT BROOKLANDS
Stan Stephens’ latest project.
As any of CMM’S readers who have ever built a special will testify, it always takes a lot longer than you thought it would: I should have known because I have built a few over the years. I thought my Brooklands Special lookalike would be running this summer, no, maybe next summer! I wanted to build the bike with all the specialist work carried out by people using the old methods that would have been used in the prewar days of Brooklands, unfortunately those guys are very busy and it meant joining a rather long queue. The biggest job was going to be the frame, which was going to be built by Terry Mead, who is well-known for building classic frames and one of the few frame-builders who take on these crazy projects. Terry gave me a start time of April but before he could begin I had to get everything ready that he would need. I had bought a Yamaha Road Star
Warrior engine from the USA, a massive 1700cc V-twin which to start with I am going to leave standard, I will be tuning and big-boring it later and also lightening it! I converted it to chain-drive from the American belt-drive with it driving down the right-hand side like the more modern Yamaha MT-01. I needed a set of period girder forks which I found were like hen’s teeth and with those that were for sale the sellers obviously wanted to retire from the profits. I found on ebay sets of new girder forks and they looked perfect. There were girders for many old British bikes and I went for a set from an Ariel Red-hunter. They looked great in the photos and were a good price, the only problem for me was that they came from India. I once had a takeaway Indian meal and found an old dishcloth in it so I was sceptical, but they looked good. They were newly-made in India and were stove-enamelled in gloss black and all the fittings and springs were chrome-plated. When they arrived they were hand-painted with red lead paint and all the fittings and springs were in bare metal and the workmanship was terrible, but at least there was a set of girders that we could use as a starting point. As you can see from the photo I found somewhere to put them! The other main part I needed before Terry could start was a set of wheels. To
keep the period look they had to be drum brakes and all the drum brakes I could find were tiny little items but a friend of mine, Jamie Wilson from Candy Wheels, came up with a set of early Honda CR250 hubs. Jamie does all the stove-enamelling that you see on all my engines and as you may gather from the name of his business he is also a wheel builder – he builds wheels for all the major motocross teams. When I told him what I was building he offered to build the wheels. What a result! All the old Brooklands bikes used skinny 21in wheels and finding tyres was going to be a problem, but my son Harley came to the rescue. Harley does all the PR for Pirelli at the BSB meetings and he managed to come up with a pair of 21in tyres, so thank you Pirelli! Jamie came up with a couple of 21in rims, which he
stove-enamelled in gloss black. The CR250 hubs were in a bit of a state, while the brake-drums were badly worn and needed skimming on the lathe. The wheel spindles looked a bit spindly for the weight and power of a 1700cc motor, the front spindle was only 15mm in diameter and the rear 17mm. I sourced some bearings with an internal diameter of 25mm but obviously the outside diameters were also larger. With the hubs mounted on the lathe I machined out the brake-drums and bored out the bearing housings at the same time. I also made new bearing spacers and bored out the brake back plates. Jamie then stove-enamelled the hubs and back plates in gloss black. Then it was over to Jamie to build the wheels. I built spoked wheels back in the days when all bikes had spokes and when they crashed the insurance company would only pay for a new rim. What I did then and I am sure everybody did, was to tape all the spokes together in their groups of four before all the nipples were undone. I then lifted off the old rim and placed the new rim over the spokes, which were already in the correct pattern and refitted the nipples and retrued the wheels. Simples, but to start from scratch with a different rim and hubs and no spokes or
pattern, now that is a different job and skill entirely. Jamie reckons to build a normal wheel with new genuine spokes takes around an hour but to build the wheels I needed would take at least three hours each. It’s a far more complicated job than I realised. When building one-off wheels there are many measurements that have to be taken first. Rims for this sort of job are supplied undrilled. The large dimples that the spoke-nipples locate in have to be drilled to the correct angle. To work that angle out, the width of the hub and the diameter of the centre-line of the spoke holes are measured and the rims drilled to suit. The spokes have to be too long and without threads. With the drilled rim in place over the hub, the spokes are fitted as a mock-up. The rim is then spaced up until the hub is central in the rim. The spoke lengths are then measured and the mocked-up wheel is stripped again. Next came the part that really surprised me. I suppose I thought that because the spokes used came without threads that the threads were made by using a die on each spoke to cut the threads. Jamie explained that by cutting the threads like that the spokes break at the end of the threads and that the threads have to be “rolled”. He
led me to one of his outbuildings to show me his spoke thread-rolling machine. He acquired it from one of the old British bike-building firms (Triumph he thinks) at an auction. I think it may have actually pre-dated the Brooklands era! The spokes, which have been cut to the right length, are each popped into a hole in the machine, when the go button is pressed, two blocks with the threads cut into them slide by each other squeezing the spoke between them and, hey presto, the spoke has a thread rolled on it. It is a very antiquated and time-consuming method, but very prewar and very British motorcycle industry. It was time to start building the wheels. Jamie builds the spokes onto the hubs first to get the pattern right and then lowers the rim on, which is common-sense to anyone who has ever tried to fit one or two spokes to a wheel that is already built. With the wheels built it is time to true them. With a clock-gauge located onto the side of the rim and another one onto the outside diameter of the rim, the wheel is trued for up and down true and for side to side. It is time-consuming, but it shows the old skills exist. I had the wheels and forks, so it was time to ring Terry Mead and say that I was on my way for the frame! cmm