Shimano UN55 Bottom Bracket British Thread, 122.5mm x 73mm



Fitted bundle deal

includes Accessories + Fitting

Item: 537151

Shimano UN55 Bottom Bracket British Thread, 122.5mm x 73mm


The sale price is SAVE £7
RRP £26.99 *

Intervening prices may have been charged

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FREE Click & Collect

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

    The Shimano UN55 Bottom Bracket British Thread is a great sealed cartridge bottom bracket with a square tapered spindle that is sturdy and robust construction.

    Shimano UN55 Bottom Bracket British Thread : Extra Info

    • Square tapered spindle
    • Sealed bearing design
    • Cartridge design for easy installation without the need for adjustment
    • Highly accurate bearings for excellent durability and smooth operation
    • Size: 122.5mm x 73mm
  • Material: Steel/Aluminium
    Type: Bottom Brackets
    Weight: 354g
  • Shimano UN55 Bottom Bracket British Thread, 122.5mm x 73mm is rated 3.8 out of 5 by 6.
    Rated 4 out of 5 by from Was given the wrong part I got one of the website, instead for getting the one I ordered, I got this one, and now I don't think I can take it back, so my stars don't mean anything
    Date published: 2018-03-12
    Rated 4 out of 5 by from Great product shame about Halfords Shamans BB is great, nice smooth action. Easy to fit.
    Date published: 2017-08-22
    Rated 1 out of 5 by from Poor quality thread on one side One side would screw in no problem but not the other side. It wasn't the female thread on the bike as the side that did engage worked fine on both sides. Disappointing and will need taken back.
    Date published: 2017-08-02
    Rated 5 out of 5 by from Great quality item at a great price The bottom bracket on my "Trek 3700 (2009)" mountain bike was very worn, and had a lot of play in the bearings. The sealed cartridge had fractured into 2 parts, and was only held together because the ends were screwed into the shell. The BB still worked, but had a gritty, very loose feel when pedalling, and could have completely failed at any time. So I set about finding a replacement ... The original BB was an "SR SUNTOUR, BB8XCT-SQS-GI, 73x124mm, BC1.37x24T" I couldn't find a replacement that was 124x73mm. The nearest I could find was 122.5x73mm. Halfords were offering the best price for a BB of those dimensions, so I ordered one via their web-site for collection from my nearest store. It was a simple job to remove the old worn one and replace it with the new one. Then all that was necessary was to adjust the front and rear derailleurs to allow for the slightly shorter BB axle. It was such a transformation having a smoothly operating Bottom Bracket. To replace a Bottom Bracket you'll need the following tools: * To remove/insert the crank bolts - an 'allen key' or 'socket' (depending on the type of crank bolt) * To remove the cranks - a 'crank puller' or 'tapered crank puller' tool (my cranks were on so tight that a normal crank puller just stripped the threads, so I had to use a 'tapered crank puller') * To replace the bottom bracket - a 'bottom bracket' tool (there are different types so ensure you get one that's suitable for your BB) * To adjust the derailleurs - a 'small screwdriver'
    Date published: 2015-04-29
    Rated 4 out of 5 by from Easy to fit, but a little noisy in operation Very easy to fit, with no adjustments necessary (initially, see below). The unit comes with a sleeve for the right hand end that is loaded with a gap filler, and the unit comes supplied with crank bolts, however these are hex bolt head type so I couldn't use them and had to reuse the bolts from the old bottom bracket. The unit has been fitted and used on a 20 mile ride - there is a creak when pressing hard on either pedal, so the gap filler clearly isn't doing the job. I plan to disassemble and fill the gap to stop the creak.
    Date published: 2014-08-31
    Rated 5 out of 5 by from Easy to install I bought this as a replacement for a worn out bottom bracket , amazing value for money as it was discounted on the website very pleased with the simplicity of fitting so now I don't have to worry for at least another year
    Date published: 2013-12-31
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    • clientName_halfords
  • UK Delivery

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

    Please allow 3-5 working days for delivery. Your delivery date will be communicated at checkout.


    UK Delivery

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    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
    Please allow 3-5 working days for collection. We'll text you to let you know when your item are ready to collect. We'll hold your item in store for seven days. All delivery times will be shown during checkout.


  • Halfords - Our Price Match Promise

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    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
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    • 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.
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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 UN55 Bottom Bracket British Thread, 122.5mm x 73mm

£19.99 The Shimano UN55 Bottom Bracket British Thread is a brilliant seal cartridge bottom bracket