# Brampton track crank arms with Aluvac 46t chain ring sprocket



## dave429 (Jan 8, 2020)

Looking for info on this crankset. What years or era,  rare or desirable? Any other info? Thanks!


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## Roger Henning (Jan 9, 2020)

See my response in your other post.  They are not special and were used on English and other 3 speed bikes. Roger


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## juvela (Jan 9, 2020)

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what is the length?

for Brampton of this era one would expect 6 1/2"

what is the wedgebolt size?

for Brampton one would expect 3/8" / 9.5mm

a 9.0mm wedgebolt would suggest a continental origin

what is the chainwheel bolt thread?

are chainwheel teeth cut for 1/8" or for 3/32" chain?

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ALUVAC -

this is a frankish producer of cycle fittings which was active in the 1930's and 1940's.  do not have start/stop dates for them.

in addition to chainwheels, pedals, tools, and number plates were offered.  found one report that they did a derailleur in cooperation with Freres Huret; it was product nr. 3716.

ALUVAC alloy pedals on a REXA machine of the 1930's -





Number plate -









Tool -





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## dave429 (Jan 9, 2020)

I have seen the Aluvac chainring used on track racer bikes. Is this something that would commonly be used.


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## bulldog1935 (Jan 10, 2020)

46T is exactly the chainset used on lightweights with internal geared (Sturmey Archer, etc.) rear hubs, just as @juvela showed.
A track chainset is probably going to be 54-58T


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## dave429 (Jan 10, 2020)

Okay, thanks for the info!


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## juvela (Jan 12, 2020)

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Here is another chainset wearing a five-pin ALUVAC chainwheel.







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## fat tire trader (Jan 12, 2020)

bulldog1935 said:


> 46T is exactly the chainset used on lightweights with internal geared (Sturmey Archer, etc.) rear hubs, just as @juvela showed.
> A track chainset is probably going to be 54-58T



Wow, I rode on the Encino velodrome for a few years and never used a front chainring that big. Most modern and vintage track bikes that I have and have seen have front chainrings smaller than 54T.


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## bulldog1935 (Jan 12, 2020)

well, if you were on 46T you were watching everyone else go around.


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## dave429 (Jan 12, 2020)

juvela said:


> -----
> 
> what is the length?
> 
> ...



Crank arms are 7.5” overall and there is a B stamped on the inside.


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## juvela (Jan 12, 2020)

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Thank you.    

Trade convention for crank length measurement is center of spindle hole to center of pedal hole.

Appears they are 6 3/4" / ~170mm which is the continental standard for adult machines.

AFAIK the letter B does not _necessarily _make them Brampton.

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## dave429 (Jan 13, 2020)

juvela said:


> ----
> 
> Thank you.
> 
> ...



Any idea what the  B could  mean? It’s on both arms.


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## juvela (Jan 13, 2020)

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Have seen Bianchi cycles fitted with cottered steel chainsets where the inner face of the arms is marked with a letter B.

For these , the possible makers would have been Magistroni, Way-Assauto and Fratelli Brivio.

IIRC I have such an arm in my parts boxes.  Will see if I can locate it in the coming week and check to see if the font employed matches that of your set.

"Usually" with the Bianchi ones the name is marked on the outer face.

Do not wish to suggest that B could not stand for Brampton.

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Thus far readers have not been informed as to:

a) correct length measurement

b) pedal thread

c) intended spindle diameter

d) wedgebolt size

e) dentition: is it cut for 1/8" chain or for 3/32"

f) thread of chainwheel bolts

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## juvela (Feb 17, 2020)

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Regarding the ALUVAC term -

it looks like that at one time it could be both a brand name and a synonym for dural and duralumin...much like CEGEDUR was.

in this post at disraeligears the host writes about its use on a Huret rear mech of the 1940's:





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						Huret Dural Competition derailleur
					

This Huret derailleur is often referred to as the Huret Aluvac as it has the word ‘Aluvac’ cast into the back of the main arm. The real name, with which André Huret blessed it, is the Huret Dural Compétition. I suspect that Aluvac refers to some kind of vacuum casting of aluminium used in its...




					www.disraeligears.co.uk
				




there is a current ALUVAC entity in operation in France.  their business seems to be concerned with the control of humidity in indoor environments.









						ALUVAC - Aluvac
					

ALUVAC société spécialisée dans le traitement de l'humité et assèchement des murs. Profitez de l'expertise de ALUVAC pour faire un diagnostique humidité.




					aluvac.fr
				




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