Grey Flash 2751

The history and restoration of a Vincent HRD Grey Flash

The rear chain adjusters, which were made for me, to pattern, by Vic Olsen have been fitted up.

These t-bar adjusters were a special racing item. They are easier to adjust under racing conditions and also give an easy visual indication enabling each side to be adjusted incrementally. I had them cadmium plated and it doesn’t appear to have taken very well – the resulting patchy finish fits the project perfectly.

The gear change linkage as acquired.

We knew that this side was going to present more head-scratching. The correct configuration hanger plate was fitted and the gear linkage parts loosely assembled.

This shot shows the linkage assembled from what we had including a Black Lightning gear change lever. Position of the lever pivot on the hanger plate is incorrect.

The hollow FT256AS tube for the rose joints is clearly too short – this would have originally been fitted to a Black Lightning which employed the Vincent “unit” gearbox. So, a new tube was manufactured. We will have it cadmium plated at a later date.

Re-manufactured adjusting tube fitted. The pillion footrest has also been fitted.
With the correct gearchange lever in place but the rubber not yet fitted.
A nipple and nut has been fitted to the gear change shaft on the Albion gearbox. The arm appears to be original.

As acquired, 2751 featured a mix of foot controls. We have looked at each component carefully to assess provenance and made a decision whether to employ the part in the restoration, replace with the correct item (I have a stock of NOS racing foot control components) or remanufacture to correct specifications.

Both footrest control hanger plates were incorrect and fabricated by Peter Johnson. Some time back I had acquired a set manufactured to the correct dimensions and drilled as per original.

The re-manufactured plates.
As acquired, the brake controls appeared thus.

From this shot we can deduce that many components have been fabricated though the pedal appears to be of the original racing type.

Correct-type plate in place and authentic linkage parts fitted to the pedal. Note footrest.

Once the linkage components were loosely assembled we could see that we were going to achieve a good result on this side without too much trouble. An NOS G108/1 arm and other original parts were employed. One of the pillion footrests was also fitted up. Very early racing Vincents featured these until the purpose made knurled racing footrest was introduced a little later on. It was also noted that the pedal pad was in road-going configuration and need to be reversed – the above shot was taken after it’d been reversed.

The pedal arm with the pad in road-going mode as acquired (top). Below is an NOS pedal with the pad correctly assembled as per racing type.
A close up of 2751 being raced in period. The pillion footrest/rubber and reversed pedal pad are clearly visible.
Having ascertained what was what and dry built the brake side we felt happy with the result.

The correct size 20″ x 2.1/2″ Borrani rear rim (supplied by John Hanson) has been laced to the hub and fitted to the rear fork. The rim was not as good a condition as hoped and the wheel builder had a bit of a job tweaking it to run true.

20″ Borrani now in place.

Being of the correct pattern, this will suffice. It will be adequate for display and demonstration but we would never advocate it being relied upon at high speed or in competition. There again, many of the original components being employed in this restoration fall into this category (the Elektron brake plates spring to mind).

A new tyre was ordered for the front rim as the state of the one fitted when acquired was unacceptable.

The rear hub features a hollow axle which passes through the hub and is secured by a nut at each end. These nuts sandwich the hub/bearings and brake plates together allowing the entire rear wheel assembly to be installed into the rear fork as one unit. This is also the method employed for the front wheel. We have already noted that the two H55 grease retainers were omitted – Peter Johnson has commented that this was to reduce friction. He mentioned that the bearings were lightly oiled before each race to compensate for this omission – a crafty race tip! Clearance is taken up by adding shims between the bearing and the shoulder on the hollow axle on each side. This was noted to be spot-on. Brake plates are then added to this “sandwich” and, with the thin retaining nuts tightened, shims further added so that the hollow axle doesn’t protrude beyond these nuts. It was noted that there was an absence of these shims which had allowed the hollow axle to stand a little proud at either end. This had caused the fork to come into contact with the protruding axle and slight damage to the threads had been sustained. This can easily be rectified and the original hollow axle retained.

The hollow axle standing slightly proud from the retaining nut. Damage to the threads at each end of the axle meant that this nut was difficult to remove.
The notorious eared nut…

This nut secures the special bolt (T-bar on road models) that passes through the hollow axle fixing the wheel/hub assembly in the fork. The tab fits into the drive chain adjusting slot and requires no spanner as it is held in place and won’t rotate. Many a Vincent rear fork has been damaged by an uninitiated owner apply a spanner to this nut… Surprisingly, instead of the tab shearing off the casting tends to split and brazed repairs to the casting are a common sight. 2751 is, unfortunately, no exception to this.

The missing H55 grease retainers and H25/4 bolt.

Instead of the T-bar, featured on road-going models, the racers employed a special waisted bolt which will have to be manufactured as it’s not present.

The rear brake plates are the original magnesium racing items.

All fixtures and fittings here appear original and correct to the bike.
The lightened brake cams are also visible.
Rear brake drums and plates with shoes fitted.

The sprocket is a lightened item and will be left. The original finned drums disappeared when the bike was in bits ‘n’ pieces many years ago – it is suggested that someone who went to look at the project took them away with them as they were a desirable upgrade over standard road-going unfinned items. Drums fitted to the rear differ in that one is drilled to prevent water build-up. Shoes are good with plenty of material. No bearing seals were fitted but there was no grease contamination present.

It was decided that before fully stripping the bike down it would be advantageous to work out the correct angles for the mudguard blades and stays. To do this necessitates lacing up the correct size rear rim. A 19″ Borrani is currently fitted but I’d acquired a correct 20 incher some while back from John Hanson. This has been sent off with the hub to be laced up and a new tyre fitted. Spokes will be zinc plated steel and we won’t be able to re-use the nipples as they don’t suit the 20″ rim.

The hub is of the 10 bolt pattern and unpolished. It’s highly likely that this is original to the machine as 10 bolt hubs were only standard on racing Vincents and the higher performance Black Shadow models.

Having chronicled the known history and listed the parts unique to the Grey Flash model, and this bike in particular, I will shortly start publishing, on this blog, posts detailing the restoration process. Since I acquired the bike in 2008 I have diligently researched what parts fitted were original and not, what parts I needed and their special finishes. Many rare parts not present were sourced and are awaiting attention. Considerations on just how much attention to give these parts will need to be addressed. Also, whether to re-finish or leave as-is and how to go about replicating or preserving the many finishes unique to this particular Grey Flash. As the bike is disassembled, each component will be carefully examined for originality and decisions made about how to proceed.

As of this week – 3rd March 2020 – work has commenced! To follow progress please click on ‘Blog Feed’ from menu.

When I acquired 2751 it was fitted with a BT-H BKH1 magneto.

Nearly all Grey Flashes were fitted with BT-H TT magnetos so I knew this was not correct to the bike. Also, the retard fitting was for the opposite rotation. I wasn’t expecting to be able to find a BT-H TT magneto very easily but I started making enquiries and keeping my eyes open.

Then, in conversations with David Dunfey and Bill Hoddinott, the following detail was brought to my attention:

The Works Order Form mentioned that the magneto was actually a Lucas.

David and Bill surmised that this could mean that 2751 possibly left The Works fitted with a Lucas K1FTT racing magneto… Now it is known that of the total production of around 30-odd complete Grey Flashes 24 were fitted with BT-H units, 5 had the Works Order Forms left blank and only 2 mentioned the fitment of Lucas magnetos…

The Lucas K1FTT magneto is a mythical device that only a very few people knew about and even fewer had actually ever seen. The Lucas KVFTT racing magneto, as fitted to the Black Lightning, is a legend in its own right but more widely known about. Larger numbers of KVFTTs were manufactured (somewhere between 50 – 75 units) and they sometimes come onto the open market and change hands for large sums. But the single cylinder K1FTT is a true rarity worthy of the much abused “unicorn” epithet. No one knows how many were made but is possible that as few as 10 units may have been produced.

Lucas racing magnetos were manufactured in a dedicated facility and the fully assembled units were shipped to a laboratory for careful testing before being sent out to suppliers and customers. Each unit passed by the laboratory had a number with an ‘LT’ prefix stamped into the body. Bill Hoddinott wrote about this special laboratory and the various Lucas products tested there in his illuminating BLACK LIGHTNING/GREY FLASH column for the Vincent Owners Club magazine, MPH (MPH 743).

Well, now I knew that it was highly likely that 2751 had left The Works fitted with this very special item but (i) I needed hard evidence and (ii) I needed to try and acquire one, for no matter how carefully 2751 was restored it would always be a disappointment to tell people that the bike had once been fitted with an extremely rare racing magneto… The odds of me achieving either of the above two requirements seemed utterly and completely remote.

My quest for information and parts continued and then I made contact with David White in New Zealand. David is mentioned in the ‘History’ portion of the blog and later the ‘Fuel Tank’ section. It was thanks to David that I was made aware of period shots of 2751 racing and it was David that later introduced me to Ian Neilson, who had the original petrol tank in his possession and agreed to swap it for the one on the bike. Well, this part of the story concerns the period photographs that David sent me copies of. Several were fantastic atmospheric shots but one image was an absolutely cracker… It featured Len Perry at considerable speed, his face a study of concentration. The rear forks appear to be quite loaded to the point that the tyre is deformed by the forces at work. Len appears to have hit the bottom of a dip and is banking left with three fingers on the clutch lever. By any standards this was a beautifully evocative shot of man and machine in harmony and right on-the-limit. The New Zealand sun behind him, perfectly illuminated every detail of the drive-side of the bike and it was pin-sharp. And there, plain to see and crisply recorded was the magneto!

‘LV Perry 1952 Hamilton 100’

I immediately forwarded the photo to Bill Hoddinott and David Dunfey and was told that the magneto was like nothing they had ever seen before and thus highly likely to be one of the mythical K1FTTs. I was elated and now had the proof that I needed. How to go about finding an example let alone acquiring one – the second task seemed impossible…

Then, one day I was sifting through various Vincent-related sites on the ‘Net and came across something regarding Lucas K1FTT magnetos – I think it was on It was just a mention about the fact that there apparently was such a device made and a name was included. This was a name that I was familiar with and it mentioned that the man supposedly had in his possession a K1FTT! I made an enquiry through a mutual contact and was able to confirm that the man in question did indeed own a genuine K1FTT, still had it and knew precisely what it was and how rare it was. My friend suggested that I call him…

I had met this gentleman once before when the mutual friend and I visited his house. We’d been shown some of his rare Vincents and I’d enjoyed a cup of tea and some of his mother’s homemade cake in their kitchen whilst I listened to him talk about the marque – he was very knowledgeable. I called him and we spoke at length about the K1FTT. Yes, he did have a complete unit that he’d bought some years previously. He really didn’t want to part with it, at any cost though… Before we hung up he did hint that he might consider parting with it if I could prove 2751 had originally been fitted with one of these rare magnetos. This sounded promising, so I emailed him the above shot of Len Perry and waited for a response… Some days later the mutual friend contacted me and informed me that he (the man in question) would like to meet with me during my next trip back to the UK.

Several months later, in November 2008, I called him from my parent’s house in Suffolk. He lived some 3 hours away but kindly agreed to travel across to me and rendezvous in Bury St Edmunds. He told me that he would bring the magneto with him and instructed me to bring my chequebook! We met in a car park and adjourned to a nearby café. The magneto was laid on the table, wrapped in a cloth. I carefully unwrapped it and there it was……..a complete and very original looking Lucas K1FTT…

A figure was mentioned and I spent the good part of an hour trying to negotiate him down to no avail… Then he told me that even if I offered him 1p less than what he was asking he wouldn’t accept it! And fair play to him, I mean, he’d graciously agreed to part with something I desperately needed and was never likely to be offered again. I immediately conceded and wrote him the cheque!

Here is what I bought:

Still showing plenty of the original grey painted finish, the Elektron magnesium body in fine condition.
K1FTT 8 49 (August 1949)
The number with the LT prefix is the laboratory testing number.

I brought the K1FTT back to Japan with me and sent photos through to David and Bill – it was a triumphant moment.

The next issue though was who to get to overhaul this rare magneto for me… I ran it past several respected enterprises and though they were keen to do the work I wasn’t instilled with enough confidence to make a decision.

Then in 2012 Bill Hoddinott interviewed Barry Basset of Coventry for an article that was published in MPH, the club magazine. Barry had worked for BT-H, knew the intricacies of magnetos on a molecular level and, though retired, still worked from home rebuilding mag’s when asked to. I thought that Barry would be the ideal man to undertake the renovation of the K1FTT, so I ran it past Bill and he agreed with me. Bill and Barry were good friends and I knew Barry realised the significance of what I would be asking him to work on. I packed it up and had it delivered to Barry by courier in November of 2012.

The rebuild was written-up in detail for an article in MPH, appearing in MPH 775 of August 2013.

Upon disassembly, all the parts made from Elektron were found to be in good condition: the main body, end plate and contact breaker cover.

The contact breaker cover.

As mentioned previously, it was stamped ‘8 49’, meaning that it had been manufactured in August 1949. We know that 2751 had left The Works in November 1949, so the date of manufacture fitted the timeline perfectly.

The disassembled K1FTT.

The armature was found to be of the universal variety fitted to all K1F, K2F and KVF models. No one-piece Monel drive spindle end cap was present – this special corrosion resistant alloy was employed in later Lucas racing magnetos. As the armature was unserviceable and didn’t differ in any way from reconditioned armatures that Barry held in stock, it was replaced outright.

One modification was performed to the magneto body: a small amount of material was relieved where the oil seal seats to enable a modern garter-spring oil seal to be fitted. This mod’ was undertaken to prevent oil ingress due to the pulsating pressure in the crankcase that invariably causes the early-type oil seals to fail. This work was carried out on the recommendation of Barry and with the agreement of Bill.

A good area of original grey paint was discovered under the brass plaque:

This was computer-matched by a paint shop and the body was etch primed, given an undercoat and then a topcoat.

The clip-fitting contact breaker cover was of the same type as used on very early KVFTT units. It was cleaned and left as-is rather than risking having it re-chromed. In addition the chromed end cap was crimped onto the Elektron breaker cover and would have been impossible to remove without damaging both parts.

The magneto was reassembled, magnetised fully and tested. I collected it from Barry in May 2013.

The directional arrow and Lucas script cast into the body were left in plain grey and not in-filled with red paint. No traces of different coloured paint were found prior to restoration.

A very satisfactory conclusion to a rather long tale involving much detective work and a lot of serendipity. Certainly, fitting this magneto and re-uniting the original tank to the bike will be a momentous occasion and one that I look forward to with great anticipation.