10. Wheels and Brakes
As I know most Vincent enthusiasts are aware, post war racing Vincents
(both Black Lightning's and Grey Flash's) were fitted with uprated brake
systems over the standard road going Vincents.
|Not Much to Start With
As the title suggests, wheels was one of the areas most lacking when I first acquired my Vincent. In amongst the bits and bobs there was a good condition bare front hub but not very much else!
There was also one standard rear brake drum, to which had been shrunk on an alloy-finned muff. Although this had been well executed it was not original so I decided not to use it. There were also a pair of reproduction Lightning plates, of which one had been obviously bent around the cam spindle bearing (the seller had made it clear to me that this was for a pattern only, in fact I think I remember his racing crash that had caused this). As I say, these plates were reproduction and of the variety where the scoops had been cast integral to the plate, which personally I have no love for (I was told once that they might actually be stiffer than the originals because of this, not sure if that is true).
|Finally, there was one interesting component
in amongst the bits, an alloy back wheel sprocket carrier. I was told by
the seller that he thought this might be genuine Black Lightning. I had
seen similar sprocket carriers used before on racing Vincent's, particularly
sprinting Vinnies, where there was some risk of the stress of a standing
start causing the normal drum/sprocket carrier to shatter.
As I find twin brakes on the rear of dubious advantage anyway (I don't even use the back brake on my Fireblade) I liked this idea, it also had the added advantage of reducing unsprung weight that the second drum/shoes etc would add.
Since first purchasing the bike I have seen a photograph of an Egli that has an almost identical sprocket carrier, so am not sure if it might be an Egli component or if Fritz Egli had got hold of an original Lightning part. Not really too worried actually.
This 1969 Egli photo just shows similar item
|In for a Penny . . .
Luckily, at the time I bought the bike (1988'ish), almost all wheel parts were readily available, which meant all I had to worry about was the money! I decided I would go the full hog, and buy everything I needed new, and blow the expense. It was here that I first took a step I was to repeat many times over the next few years, I sold one of my other bikes to finance the build!
I bought a complete set of alloy brake plates, 2 fronts and one rear, from Ted Davis. These included the separate scoops and were of beautiful quality. I am not sure if they are still made, but they do look the business. I believe that some original Lightning plates were made of Magnesium, although I don't know if they were all made such? If they were I would be a bit concerned about their strength for racing by now.
|Ted also gave me a very interesting snippet of information about the original Lightning's. Supposedly even the brake spindle cams (H10/1) were drilled through the flat of the lobe, for lightness! As these are not hardened it is not a difficult job to carry this out. With unsprung weight, every little helps.|
|Virtually all of the other components came from Tony Maughan, rear hub, finned brake drums, shoes, bearings, stainless spindles and so forth. I have to say they made a gorgeous site all laid out when I got home, not unlike building a new bike I guess.|
Building the Wheels
Once the hubs were in situ with the hub, I mounted the whole unit in the lathe and gave the brake drum surface a very fine skim. This ensures the drum are absolutely true to the hub and is something that used to be done by many racing people to ensure the brakes were as perfect as possible.
|Next step was to mount the shoes
on the brake plates. I had previously two-pack painted the brake plates
gloss black (including etch primer) so they looked very pretty. The shoes
had had Ferodo AM4 (green) racing linings bonded to them.
Once the shoes were mounted on the brakeplates, I added additional shims so that the shoes were opened sufficiently that they would not fit into the brake drums with the cam in the 'off' position. This might sound a little strange; however, I then mounted the brake plates on the lathe and carefully turned the shoes down, so that they were a perfect fit into the drum. Having then removed the additional shims, it ensures that when applied, the shoes have perfect contact all round the drum.
My Norton uses a similarly prepared front brake and I can vouch that taking these steps makes the difference between mediocre and 'on yer nose' braking. Hope it works in this case!
The nice thing about Vincent wheels is that all this can be done before lacing the hubs to the rims, meaning it can be performed on a reasonable sized lathe.
I believe Lightning's were not as a rule fitted with Tommy Bar spindles, however, I like these so much I decided to fit them anyway (yes I know, they are heavier!). I think my rationale with these was that if I do decide to race the bike seriously, then it is a simple job to replace these with plain lightened spindles. Tony Maughan supplied these in Stainless Steel and (as always) the finish is gorgeous.
Completed front wheel showing speedometer blanking plate
|Rims and Tyres
At the time I was building the wheels (approx 10 years ago) I had every intention of racing the bike seriously, therefore I was more concerned about the race rubber available than originality. For this reason I had decided to opt for 18" rims.
Original Black Lightning's were fitted with 21" rims front and 20" rear, both in alloy. I believe they were stamped 'Rekord'. Even if I could have found alloy rims in this size, there is to my knowledge no race rubber available in this size (I am still looking for rims in this size now though, in case anyone out there has a set!).
I did toy with 19" rims briefly, but at the time the only 19" race tyres available were Avon GP's. These are excellent tyres (I had them fitted to my Norton), but going 18" allowed a better selection and slightly wider rear profiles. I opted for WM2 front and WM3 rear. Dunlop rims are no longer available new so I went for Akront beaded rims, which are never the less very pretty.