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1948 Vincent Black Shadow

Pretty much anything not covered by the topics above. Short lived production bikes or vehicles, Electrical, Tires, Paint, Brakes, etc. Use this for tech questions, and "Shoot the Bull" for general conversation, no tech.
Post Thu Mar 31, 2011 5:49 pm

Posts: 141
Location: USA
What size front wheel was the 1948 Bonneville Vincent Black Shadow was running?Thanks. :D

Post Sat Apr 02, 2011 4:16 pm

Posts: 591
Location: Crewe, Great Britain

Hi, celticdodge...

:? I believe it was called an HRD at the time!!! Still, it ran either 20 or 21 inch at the front...


Post Sat Apr 02, 2011 9:05 pm

Posts: 1676
Location: Interlaken, NY USA

I have a picture of my Dad's buddy on his postwar Vincent Rapide, I think 47 or 48, and it has Both " Vincent" in a banner directly above the capital letters "HRD" on the tank decal. The Vincent lettering being maybe 1/2"-3/4" tall, and the HRD being about 2" tall. Likewise, the timing chest cover and the pushrod caps have "HRD" on them. The front wheel looks to be a 21". I'll try a magnifying lens to see if I can make out the lettering.

Post Sat Apr 02, 2011 10:51 pm

Posts: 159
I'm fairly sure HRD's used 20 inch tyres. At least the front one anyway.

Post Sun Apr 03, 2011 5:45 am

Posts: 1654
Shoot, a man could have a good weekend in Dallas with all that stuff...

Post Sun Apr 03, 2011 1:22 pm

Posts: 141
Location: USA
Thanks for the help guys ,I am trying to replicate some of the Vincent attributes in my upcoming build. :D :D

Post Mon Apr 04, 2011 4:15 am

Posts: 1654
Vincent wheel sizes are one of the few aspects of these machines which are pretty much generic for the time. The rims and tyres were bought out from the usual suppliers and so they much the same as any other manufacturer.

as a general comment, 20" rear / 21" front is a common combination of sizes found on pre-war rigid-frame girder-fork sports bikes. 20" front / 19" rear with a slightly larger section rear tyre would be a more common combination for touring bikes and this can sometimes be found on post-war "utility" bikes with various combinations of tele forks and rigid or plunger frames.

The change to telescopic forks and/or rear suspension of various types led the the 18" rear / 19" front becoming pretty much universal. 20" front wheels are rare on tele forks and 21" almost unknown, apart from special machines for trials etc.

same-size wheels in the American style were never British practice
Shoot, a man could have a good weekend in Dallas with all that stuff...

Post Sat Apr 16, 2011 9:22 pm

Posts: 66
While Vincent fitted both 20" and 21" fronts, the 20's were always steel and the 21's always alloy since the 20" alloy rims available then were 3.50", too wide for a front Also as a practical matter if you fit 21" today you will have better choice and availability of rubber since 21s continue to be popular on choppers.

From your post it is not clear if you are trying to replicate the a Bonneville Vincent, or build a non-Vincent, but Vincent-inspired machine. If the former, there are probably better places on the net than this to get answers concerning Vincent esoterica .

Post Sun Apr 17, 2011 12:33 am

Posts: 1654
I don't really understand what you are trying to build. Vincents are so different structurally and mechanically that to attempt to "reproduce their attributes" in a conventional tubular-frame, non-unit bike is a meaningless exercise.

There have been occasional specials incorporating Vincent engines in Norton frames, usually with Norton transmissions, but these are machines of a very different character to Vincents and very rare.

There have even been occasional Vincent choppers but they are strongly disapproved of by Vin owners generally, I would say with good reason. Go on an Vincent website and ask for information to help with a chopper and you probably won't get far, although maybe further than trying to buy a machine or parts for such a purpose...

The black paint and gold lining were generic period features used by many makers, and the styling is generally conventional for the period, subject to the structural constraints already mentioned. The wheels were generic bought-out items which were common to most machines of the time

don't know if this helps
Shoot, a man could have a good weekend in Dallas with all that stuff...

Post Sun Apr 17, 2011 8:09 pm

Posts: 1676
Location: Interlaken, NY USA

45Brit, Been meaning to ask re your comment on 18"rear/19" front to tele equipped Brit bikes. I've read several times over the years that it was common for home versions of Tri's and BSA's to be fitted with 19's front and rear, but the American market wanted 18"/19's shipped to them. Sounds to me that's a bunch of eyewash from your comments. Doesn't really matter much, just a trivia kinda question, but Most all Brit bikes I paid attention to, BSA's and Triumphs, had the 18/19 combo over here.

Post Mon Apr 18, 2011 2:16 am

Posts: 575
Location: devon,england
3t ,19 front n rear
3ta, 17 "" "" to 1966 then 18 both
tiger 90 both 18
blah blah blah

6t 50-59 both 19 then till 66 both 18
t110 54-59both 19 then till61 both18
t120 59 -60 both 19 then 19 f 18 r
after 1960 standard fitment on most triumph's was 19 front 18 rear with the odd exception such as thet100s of 67-70 18 both.

taken from roy bacon's triumph twin restoration

regards jib
Dude, check out that jibhead, he's crazy. Hasn't been sober for 40 years

Post Mon Apr 18, 2011 9:17 am

Posts: 66
Actually Norvins and Eglis (Vincent engines in newer-style backbone frames, as originally made by Fritz Egli) are relatively common and turn up at most old bike meets. And now that it is possible to build a new engine from scratch, so it is not necessary to cannibalize an existing machine to build one, they continue to be built.

Ditto choppers. While chopped Vincents used to be uniformly atrocious kludges usually made by penurious Brits who couldn't afford a Harley, there have been some built recently that are really gorgeous, using new-build engines. Look up the Redneck Vincent chopper for an outstanding example.

Oh, when the Bonneville machine was built the company was doing business as the Vincent HRD Company LTD so it is perfectly acceptable to refer it as either a Vincent or HRD Vincent though not usually as just HRD.

Post Tue Apr 19, 2011 4:05 am

Posts: 1654
There are marked differences between rigid and swing-arm wheel sizes. Triumphs in particular had all sorts of odd sizes down to 17" on swing-arm bikes, even 16" on some Tiger Cubs.

my experience would be that M & B series single-cylinder BSAs, swing-arm and rigid, usually have 19" front and rear with tele forks and some pre-war ones have 20" fronts with girder forks. A series BSAs, pre-unit and unit, should have 19" front and rear. WD machines all have 19" front and rear.

Some post-war lighweights ( C10 ) have 20" fronts, which I suspect is a case of using up old stock at a time when it was difficult to source pretty well anything. Bantams have 19" both ends for rigid frames and 18" for later swingarnms versions.

That said, 18" rear wheels for non-unit bikes are a common "find", having been converted for sidecar use or for better tyre choice. US exports, don't know
Shoot, a man could have a good weekend in Dallas with all that stuff...

Post Tue Apr 19, 2011 4:13 am

Posts: 1654
I don't know about the US, but the VOC in UK will have nothing to do with Vincent choppers of any description.

On the whole I can see their point, since the Vin is/was a highly original design which represented state-of-the-art design concepts ( even if the execution was a little contentious, shall we say ) which were in some ways - such as the triangulated rear suspension and underslung, stressed engine-as-frame-member - decades ahead of their time, and was the fastest thing on the road in its day with legendary braking. They also had a long and successful record as sidecar speedway and grasstrack racers. To take such a machine and turn it into a highly subjective styling exercise in which form is subordinated to function, I for one see no point in this whatsoever and much to be said against it.

Norvins, h'mmm :? VOC have accepted them over the years but you can still expect to be less than widely admired for cutting the gearbox off, a change which can't be reversed. Again, from experience they are actually quite rare but highly visible and much-reported when they do appear.
Shoot, a man could have a good weekend in Dallas with all that stuff...

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