Shimano BB-UN55 Bottom Bracket British Thread

From £16.99


Fitted bundle deal

includes Accessories + Fitting

Shimano BB-UN55 Bottom Bracket British Thread

From £16.99

Save £5.01
RRP £22 *

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  • Description
  • Specification
  • Reviews
  • Delivery Options
  • Help & Advice
  • Price Match
  • Buying Options
  • Shimano BB-UN55 Bottom Bracket British Thread

    The Shimano BB-UN55 Bottom Bracket British Thread is a popular sealed cartridge bottom bracket with a lightweight hollow spindle. Attaching your bike to the crankset, this bottom bracket ensures your crankarm rotates like a dream. Plus, the sealed design keeps out all the nasty stuff like mud, dirt and water, which means it`ll keep working perfectly for even longer.

    Shimano BB-UN55 Bottom Bracket British Thread Extra Info

    • Square tapered spindle
    • The slim body allows clearance for cable routing under the bottom bracket
    • Quick and easy to install without the need for adjustment
  • Material: Steel
    Type: Bottom Brackets
    Weight: 340g
  • Shimano BB-UN55 Bottom Bracket British Thread is rated 4.8 out of 5 by 13.
    Rated 5 out of 5 by from Bottom Bracket Replacement bottom bracket made to usual high Shimano standard. Easily fitted and works perfectly without any creaking or vibration.
    Date published: 2018-04-29
    Rated 5 out of 5 by from Reliable shimano bottom bracket This is a replacement for. My fsa bottom bracket easy to fit and very smooth
    Date published: 2018-01-19
    Rated 5 out of 5 by from nice and smooth got this to replace the existing one in my carrera subway one . went in easy . had to twiddle the front derailier . the old out put shaft being a tadge smaller in length . the difference is astounding
    Date published: 2017-11-30
    Rated 4 out of 5 by from BB-UN55 Bottom Bracket Not much to say, this replaces an RPM BB, which is of poor quality, the Shimano appears better manufactured. Comes with a sealing paste on the threads, so is well sealed and locks extremely tightly. All in all, a good product well made at a good price
    Date published: 2017-07-17
    Rated 5 out of 5 by from Great BB This is a great Bottom bracket. I did have one issue though. It didnt screw in fully. I had 1mm more to screw in. I was then told, that its not an issue although there are 1mm washers available. Would have been better if shimano could include those.
    Date published: 2017-05-09
    Rated 5 out of 5 by from bottom bracket un55 excellent BB gradually using on all my bikes one of the few using metal casing,easy fit,durable and therefore good build quality
    Date published: 2016-10-19
    Rated 5 out of 5 by from Bottom bracket upgrade After 2500 miles I thought the original bb was getting abit rough!! Bought this as an upgrade for obvious reasons.. Great brand, great value and price matched.. Very happy with results, only took 10 mins to swap over.
    Date published: 2016-09-21
    Rated 5 out of 5 by from Excellent bottom bracket, excellent price Halfords were running a price match on this product, and it was easy to order and pick up in store. Guy in cycle department was very thorough - he went through the details of the cartridge to ensure it was the correct one.
    Date published: 2016-06-24
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  • UK Delivery

    £3.99 NEXT DAY Delivery available on orders under £40 placed by 8pm*

    Your delivery date will be communicated at checkout. Delivery times are Monday to Saturday.


    UK Delivery

    FREE Click & Collect - you can reserve an item online and pick it up from a store of your choice

    Simply enter your Postcode on the product page to check availability, and select Click & Collect at checkout. What's more, you pay for your items on collection. Click here to learn more.

    Items in stock - collect from 1 hour
    If your item is in stock at your chosen store, you can collect it from one hour after ordering online. We'll hold your item in-store for seven days.

    Items not in stock - collect next day*
    If your item isn't in stock, we can order it to your chosen store for collection.
    *If you place your order before 8pm you can collect it from 4pm the following day (except Sundays), and we'll hold your item in-store for seven days.

    Built Bikes
    Collection time will increase by 24 hours if you'd like us to build your bike for you.

    Please note that items sent directly from the supplier need to be ordered by 3pm for collection two days later. All delivery times will be shown during checkout.


  • Halfords - Our Price Match Promise

    At Halfords we strive to offer our customers first class service and products at competitive prices.

    In order to uphold our Price Promise to not be beaten on price, we actively monitor the prices offered by our competitors daily and adjust our own pricing accordingly.

    If you find a cheaper price we'll match it, and if you find it after you've purchased from us we'll refund the difference within 7 days of receipt of your goods.

    Simply take a print out of the competitor's online price into any Halfords store, ensuring, date and price are shown and we will match the competitor price if within policy.

    Terms & Conditions

    • The competitor's item must be identical (colour, size etc)
    • The competitor's item must be in stock at the time of match
    • The competitor's price must include delivery
    • The competitors price must be publically advertised online and cannot include any membership/personal discounts
    • We cannot match bulk promotional offers such as buy one get one free
    • The competitor must be based in the UK and sell direct to customers (no auction or marketplace retailers)
    • No other promotional offers or vouchers can be used on top of a price match
    • We will match within 7 days of receipt of purchase
    • We will match in store if our online price is lower than our store price
    • We will not match against clearance, closing down sales or specialist retailers such as market stalls.
    • In order to change the price of items bought on finance, the original agreement must be cancelled and a new one created at the lower price. The new agreement must still meet the minimum value and item requirements for finance.
    • Items sold by Halfords Approved Partners are not subject to our price match policy.
  • You can buy this product from one of our carefully selected Approved Partners. The full list of options available are below. Simply add your chosen option to your basket and proceed to checkout when you're ready.

    You can purchase products supplied by Halfords and selected other suppliers on

    Checkout is always via and all payment will be taken via In checkout the products will be split into separate deliveries for each supplier.

    Showing 1 - X of our buying options
    Price Seller Info Purchase

Some of the parts we sell here at Halfords have been reconditioned. These will carry a Refundable Deposit or an extra surcharge amount. When you add one of these reconditioned items to your basket, we'll add this extra cost automatically.

Once you've sent us your old item we'll check it over, and then refund you the full surcharge as long as everything is ok.

Before you return your old unit please make sure it's in re-serviceable condition. So if you're returning caliper casings, you'll need to double check they aren't badly damaged or broken. If the part you've sent is found to be unserviceable, we reserve the right not to refund the surcharge.

Please note that if you're returning your old unit to our National Returns Centre then this will be at your own expense.

Shimano Gears, Drivetrain & Cables

Shimano BB-UN55 Bottom Bracket British Thread

£16.99 Shimano BB-UN55 Bottom Bracket British Thread is at its best together with traditional chainsets.