Shimano Dura-Ace 1st Gen GB-100 NOS Vintage English Bottom Bracket Cups

Shimano Dura-Ace 1st Gen GB-100 NOS Vintage English Bottom Bracket CupsOriginal parts produced in the 1970s New old stock! Still unused after all these years Worldwide shipping Shimano Dura Ace left and right bottom bracket cup set, hailing from Japan and in production during the 1970s (yet still new & unused after all this time). Made from steel and weighing in at 78 grams (for the pair). A fine choice for keeping your vintage bike authentic, but also great for any other compatible bike. OVERVIEW Race Condition New Old

✓ Original parts - produced in the 1970s
✓ New old stock! Still unused after all these years
✓ Worldwide shipping

Shimano Dura-Ace left and right bottom bracket cup set, hailing from Japan and in production during the 1970s (yet still new & unused after all this time). Made from steel and weighing in at 78 grams (for the pair). A fine choice for keeping your vintage bike authentic, but also great for any other compatible bike.

OVERVIEW

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Race Condition - New Old Stock*
Production Era - 1970s
Country - Japanese
Material - Steel
Weight - 78 g
Stock Code - D-G3-BB-CS27V

*New old stock items may have marks from storage over the years, and as we often have multiples they can vary from piece to piece, but they are always genuine new & unused items.

TECHNICAL INFO

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Bottom Bracket Type - Square Taper
Thread Type - English Thread (British/ISO 1.37" x 24 TPI)

▼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.

▼SAFETY & COMPLIANCE

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This product complies with the EU General Product Safety Regulation (GPSR). Professional installation and regular inspections are recommended. Due to the product's age, extra care should be taken during use.

Product Manufacturer - Shimano Inc. 3-77 Oimatsu-cho, Sakai-ku, Sakai-shi, Osaka 590-8577, Japan

EU Authorised Representative - Global Trade Department NI Ltd, Office 834, Unit 6, 100 Lisburn Road, Belfast BT9 6AG, Northern Ireland

▼HELP SECTION

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Bottom Bracket Type - ‘square taper’, as the name suggests have square shaped axle ends that slot into the chainset and ‘cottered’ axles are round and secured by pins - pretty much every bike up until the 1990s would use one of these, cottered being the much earlier system.

Thread Type - this must match the bottom bracket thread on your frame. The 3 common thread types on classic and vintage bikes are English (also known as British or ISO), Italian & French, and are usually (not always!) found on frames built in their respective countries. If you're replacing cups, they often have the thread type stamped on one of them, if not there are a couple of things to look at; bottom bracket shell width (English & French = 68 mm, Italian = 70 mm) & drive side cup thread direction (English = left, Italian & French = right). The only curveball to watch out for here, although pretty uncommon, are Swiss threads (also found on some French frames, Motobecanes being one) which will have the same shell width & thread direction as an English thread frame but the actual thread pitch will be different. If none of the above matches what you have, there are a few lesser known varieties that will require some further research.