Specialites T.A. Professionnel (104) Allen Bolt Adaptor Fit Vintage 53T 152 BCD Outer Chainring

Specialites T.A. Professionnel (104) Allen Bolt Adaptor Fit Vintage 53T 152 BCD Outer ChainringOriginal part in production from the 1960s to the 1970s Suitable for historic cycling events such as L'Eroica Professionally checked & cleaned Worldwide shipping Specialites T. A. Professionnel chainring, hailing from France and in production from the 1960s to the 1970s. Made from aluminium and weighing in at 79 grams. A fine choice for keeping your vintage bike authentic, but also great for any other compatible bike too. If you're taking part in

✓ Original part - in production from the 1960s to the 1970s
✓ Suitable for historic cycling events such as L'Eroica
✓ Professionally checked & cleaned
✓ Worldwide shipping

Specialites T.A. Professionnel chainring, hailing from France and in production from the 1960s to the 1970s. Made from aluminium and weighing in at 79 grams. A fine choice for keeping your vintage bike authentic, but also great for any other compatible bike too.

If you're taking part in L'Eroica, Anjou Velo, Velo Retro or another similar vintage cycling event, this is fully compliant - so rest assured, the pre-1987 police won't lock you up for having the wrong chainring!

The chainring's been carefully cleaned, thoroughly checked by one of our mechanics and graded as good condition, but do take a good look at the detailed photos so you can see the cosmetic condition before you buy.

OVERVIEW

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Condition - Good
Model ID - 104
Production Era - 1960s & 1970s
Country - French
Material - Aluminium
Weight - 79 g
Stock Code - U-CRO24V

TECHNICAL INFO

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Tooth Count - 53
Between Adjacent Bolt Holes - 76 mm
BCD - 152 BCD
Bolt Count - 6-Bolt
Chain Width - 3/32" (Standard)
Intended Speed* - 5 Speed, 6 Speed

▼SHIPPING, TAXES & RETURNS

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We've been safely sending orders around the world since 2010. There's a handy shipping calculator on the shopping cart page so you can see the cost of postage as soon as you've added it to your basket. Your order will be carefully packed and sent with tracking & insurance, we despatch most orders within 2-3 days but larger items and orders placed before the weekend can take an extra day or two to process.

We accept returns, please notify us within 14 days and ensure the item arrives back with us no later than 30 days after the order was received.

EU Customers – for orders under €150 (excluding shipping), VAT will be collected at checkout, but from 1st July 2026, due to new EU import regulations, there may also be a customs duty payable to the carrier. For orders over €150, all import fees will be payable to the carrier, with nothing collected at checkout.

USA Customers – import fees are now collected at checkout for all orders to the US, so there won’t be any surprise charges when your order arrives.

Other International Customers – local import fees may still apply, charged by your customs office or courier before delivery. These are not collected by us, so please check your local rates before purchasing.

Any applicable fees will appear at checkout.

▼HELP SECTION

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Tooth Count - the number of teeth on the chainring, the higher the number the harder the gear.

Between Adjacent Bolt Holes - the measurement from the centre of any bolt hole to the centre of an adjacent one, if this measurement is the same as that of your crankset and the bolt count is the same then the chainring should fit.

BCD - stands for Bolt Circle Diameter (sometimes referred to as PCD - Pitch Circle Diameter) and is the technical way to determine whether the chainring fits your crankset. To calculate, multiply the distance between adjacent holes (in mm) by 1.709 (you’ll likely need to round the resulting number up or down a little).

Bolt Count - the number of bolts securing the chainring to the chainset. As with the BCD, this must be the same as your chainset.

Chain Width - 3/32” is the standard width for double and triple chainsets, wherease 1/8” chainrings are only found on single ring chainsets, generally for track / singlespeed use and can only be used with a wide 1/8" chain.

Intended Speed - the number of cogs at the back the chainring was designed to be used with. We refer to it as ‘intended’ speed as most double and triple chainsets will actually work with different speeds than originally intended, but the further away you get from the intended speed the more likely you are to experience minor setup issues. The exception being some chainrings intended for 10 speed use or higher, with these it’s better to stick to the intended speed.