For Sale UK

21 speed mountain bike

4

21 speed mountain bike for sale on Ireland's largest auction and classifieds sites

Home / Cycling / 21 speed mountain bike refurbished & used for sale | For Sale UK
Aili mountain bike 21 - aili,

Aili mountain bike 21 - aili,

£149.00 · Buy It Now

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Bike speed full suspension - 21,

Bike speed full suspension - 21,

£161.48 · Buy It Now

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5 29inch mountain - 24/26/27.5/29inch,

5 29inch mountain - 24/26/27.5/29inch,

£209.90 · Buy It Now

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Inch mountain bike speed - bike, 21

Inch mountain bike speed - bike, 21

£189.90 · Buy It Now

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Inch folding bike 21 - inch,

Inch folding bike 21 - inch,

£159.00 · Buy It Now

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Eurobike tonta mountain - eurobike,

Eurobike tonta mountain - eurobike,

£146.30 · Buy It Now

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Mens mountain bike mountaineer - mountain,

Mens mountain bike mountaineer - mountain,

£163.10 · Buy It Now

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Mountain bike disc - mountain,

Mountain bike disc - mountain,

£180.00 · Buy It Now

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Folding mountain bike - bike, 26

Folding mountain bike - bike, 26

£179.99 · Buy It Now

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Mens mountain bike mountaineer - mountain,

Mens mountain bike mountaineer - mountain,

£163.10 · Buy It Now

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Folding mountain bike - 27.5"folding, 21

Folding mountain bike - 27.5"folding, 21

£229.99 · Buy It Now

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5inch mountain bike front - 27.5inch,

5inch mountain bike front - 27.5inch,

£209.90 · Buy It Now

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Folding mountain bike - in,

Folding mountain bike - in,

£163.12 · Buy It Now

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Mountain bike inch - inch, wheel

Mountain bike inch - inch, wheel

£219.90 · Buy It Now

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Adult mountain bike front - bike,

Adult mountain bike front - bike,

£209.90 · Buy It Now

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Wheels mountain bike - bike, 21

Wheels mountain bike - bike, 21

£189.99 · Buy It Now

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Aili mountain bike - aili,

Aili mountain bike - aili,

£190.00 · Buy It Now

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Inch mountain bike - 27.5, front

Inch mountain bike - 27.5, front

£207.99 · Buy It Now

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Trioblade inch folding - trioblade, 26

Trioblade inch folding - trioblade, 26

£179.99 · Buy It Now

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Speed mountain bike - mountain,

Speed mountain bike - mountain,

£6.79 · Buy It Now

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Mens mountain bike mountaineer - mens,

Mens mountain bike mountaineer - mens,

£163.10 · Buy It Now

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Ridge speed mens - speed, boys

Ridge speed mens - speed, boys

£209.99 · Buy It Now

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Speed city hybrid - 21-speed,

Speed city hybrid - 21-speed,

£254.00 · Buy It Now

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Folding mountain bike 21 - 27.5"folding,

Folding mountain bike 21 - 27.5"folding,

£219.99 · Buy It Now

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Huffy marker inch matte sky - huffy,

Huffy marker inch matte sky - huffy,

£290.00 · Buy It Now

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Mens mountain bike - mens,

Mens mountain bike - mens,

£163.10 · Buy It Now

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Huffy korros inch speed - korros, 21-speed

Huffy korros inch speed - korros, 21-speed

£250.00 · Buy It Now

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Huffy marker inch matte - huffy,

Huffy marker inch matte - huffy,

£290.00 · Buy It Now

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5inch folding mountain - 24-27.5inch,

5inch folding mountain - 24-27.5inch,

£189.90 · Buy It Now

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Rcb26 mountain bike - mountain,

Rcb26 mountain bike - mountain,

£208.70 · Buy It Now

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Inch mountain bike 21 - mountain,

Inch mountain bike 21 - mountain,

£209.99 · Buy It Now

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Mountain bike ecosmo wheel - ecosmo,

Mountain bike ecosmo wheel - ecosmo,

£239.99 · Buy It Now

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Mountain bike licorne - mountain,

Mountain bike licorne - mountain,

£259.19 · Buy It Now

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Speed mountain bike - 21,

Speed mountain bike - 21,

£6.49 · Buy It Now

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Folding mountain bike - 24"-27.5"folding,

Folding mountain bike - 24"-27.5"folding,

£205.90 · Buy It Now

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Apollo evade mens speed - evade,

Apollo evade mens speed - evade,

£209.89 · Buy It Now

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Arden ridge speed mens - arden,

Arden ridge speed mens - arden,

£189.99 · Buy It Now

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Mountain bike - '',

Mountain bike - '',

£189.90 · Buy It Now

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Shimano folding mountain bike - shimano,

Shimano folding mountain bike - shimano,

£199.90 · Buy It Now

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Bike speed full suspension - 21,

Bike speed full suspension - 21,

£163.11 · Buy It Now

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Inch full suspension - full,

Inch full suspension - full,

£163.12 · Buy It Now

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New inch bike mountain - new,

New inch bike mountain - new,

£174.99 · Buy It Now

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Full suspension mountain bike - full,

Full suspension mountain bike - full,

£229.99 · Buy It Now

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Velvet speed ladies womens - velvet, 21

Velvet speed ladies womens - velvet, 21

£209.99 · Buy It Now

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Inch mountain bike 21 - bike,

Inch mountain bike 21 - bike,

£199.90 · Buy It Now

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Unisex mountain bike - unisex,

Unisex mountain bike - unisex,

£199.99 · Buy It Now

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5 29inch mountain - 24/26/27.5/29inch,

5 29inch mountain - 24/26/27.5/29inch,

£195.90 · Buy It Now

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Inch folding mountain - 24/26,

Inch folding mountain - 24/26,

£189.99 · Buy It Now

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26inch bike mountain - bike, 21

26inch bike mountain - bike, 21

£199.99 · Buy It Now

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Bicycle twist gear shifters - bicycle,

Bicycle twist gear shifters - bicycle,

£10.49 · Buy It Now

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5inch mountain bike - 24/26/27.5inch,

5inch mountain bike - 24/26/27.5inch,

£189.90 · Buy It Now

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Mens mountain bike - mountain,

Mens mountain bike - mountain,

£163.10 · Buy It Now

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Folding mountain bike - folding,

Folding mountain bike - folding,

£219.90 · Buy It Now

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26inch mountain bike - 24/26inch,

26inch mountain bike - 24/26inch,

£199.90 · Buy It Now

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Inch foldable mountain bike - foldable,

Inch foldable mountain bike - foldable,

£209.90 · Buy It Now

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Adult mountain bike - adult,

Adult mountain bike - adult,

£189.99 · Buy It Now

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Inch wheel mountain bike - 26,

Inch wheel mountain bike - 26,

£249.90 · Buy It Now

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Inch folding bike 21 - inch,

Inch folding bike 21 - inch,

£189.99 · Buy It Now

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Inch adult mountain - inch, bike

Inch adult mountain - inch, bike

£215.90 · Buy It Now

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Speed mountain bike - 24,

Speed mountain bike - 24,

£6.79 · Buy It Now

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Mountain bike inch wheel - mountain, bike,27.5

Mountain bike inch wheel - mountain, bike,27.5

£219.99 · Buy It Now

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Pink 26inch mountain bike - pink, 24/26inch

Pink 26inch mountain bike - pink, 24/26inch

£199.90 · Buy It Now

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Ridge speed mens boys - speed, front

Ridge speed mens boys - speed, front

£209.99 · Buy It Now

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Mens mountain bike mountaineer - mens,

Mens mountain bike mountaineer - mens,

£163.10 · Buy It Now

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Speed mountain bike shifter - 21-speed,

Speed mountain bike shifter - 21-speed,

£7.99 · Buy It Now

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Inch adult mountain bike 21 - 29,

Inch adult mountain bike 21 - 29,

£219.90 · Buy It Now

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Folding mountain bike full - mountain,

Folding mountain bike full - mountain,

£163.11 · Buy It Now

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Arden ridge speed - 21,

Arden ridge speed - 21,

£189.99 · Buy It Now

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Inch wheel mountain - wheel, bike

Inch wheel mountain - wheel, bike

£215.90 · Buy It Now

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New inch bike mountain - inch,

New inch bike mountain - inch,

£189.99 · Buy It Now

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Mountain bike 21 - 24"26“,

Mountain bike 21 - 24"26“,

£209.90 · Buy It Now

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Inch mountain folding bike - 26,

Inch mountain folding bike - 26,

£179.99 · Buy It Now

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Mountain bike 21 - bike,

Mountain bike 21 - bike,

£199.90 · Buy It Now

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Speed folding mountain bike - 21-speed,

Speed folding mountain bike - 21-speed,

£144.11 · Buy It Now

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Basis bicycle full susp - full,

Basis bicycle full susp - full,

£201.99 · Buy It Now

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Basis connect mountain bike - basis,

Basis connect mountain bike - basis,

£190.99 · Buy It Now

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Inch wheel adult mountain - wheel,

Inch wheel adult mountain - wheel,

£219.90 · Buy It Now

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5inch mountain bike 21 - mountain,

5inch mountain bike 21 - mountain,

£189.90 · Buy It Now

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5 folding mountain - 24"-27.5"folding,

5 folding mountain - 24"-27.5"folding,

£229.90 · Buy It Now

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Inch element mountain - element,

Inch element mountain - element,

£299.00 · Buy It Now

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Wheel folding mountain - 24'',

Wheel folding mountain - 24'',

£189.90 · Buy It Now

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Mountain bike 21 - mountain,

Mountain bike 21 - mountain,

£209.90 · Buy It Now

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26in speed folding mountain - 26in,

26in speed folding mountain - 26in,

£163.11 · Buy It Now

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Mountain bike 21 - mountain, 21-speed

Mountain bike 21 - mountain, 21-speed

£291.89 · Buy It Now

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Inch folding bikes mens - inch,

Inch folding bikes mens - inch,

£163.11 · Buy It Now

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Inch adult mountain bike - 24,

Inch adult mountain bike - 24,

£188.90 · Buy It Now

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5 29inch mountain - 24/26/27.5/29inch,

5 29inch mountain - 24/26/27.5/29inch,

£195.90 · Buy It Now

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Shimano folding mountain bike - shimano,

Shimano folding mountain bike - shimano,

£199.90 · Buy It Now

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Inch adult mountain bike - inch,

Inch adult mountain bike - inch,

£209.90 · Buy It Now

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Pink 26inch mountain bike - 24/26inch,

Pink 26inch mountain bike - 24/26inch,

£189.90 · Buy It Now

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Folding mountain bike 26 - 24",

Folding mountain bike 26 - 24",

£189.99 · Buy It Now

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Diamondback overdrive mountain - diamondback,

Diamondback overdrive mountain - diamondback,

£104.70 · Buy It Now

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Speed folding mountain bike - mountain,

Speed folding mountain bike - mountain,

£144.11 · Buy It Now

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Mountain bike licorne guide - mountain,

Mountain bike licorne guide - mountain,

£142.14 · Buy It Now

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Twin mountain bike - b’twin,

Twin mountain bike - b’twin,

£89.10 · Buy It Now

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📊95 listings · from £6.49 · avg £186.84
⚠️ These listings were last updated more than 16 days ago. Search for fresh listings

Browse 95 21 speed mountain bike listings currently in our index. Prices range from £6.49 to £299, with an average of £186.84. Whether you are hunting for a bargain or looking for a top-spec model, the selection below covers all price points — new, used and refurbished. More about 21 speed mountain bike →

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Everything you need to know about 21 speed mountain bike

Whether you are looking for a brand-new or second-hand 21 speed mountain bike, eBay offers one of the largest selections available online. With 95 active listings at the time of this page's last update, you have plenty of choice across different conditions, sellers and price points. The cheapest option currently starts at £6.49, while premium listings can reach £299 — giving you a wide budget spread to work with. The average price of £186.84 can serve as a useful benchmark: listings below this tend to be used or auction-style, while those above often include extra accessories, warranties, or are sold by professional sellers with high feedback scores. Always check the seller's feedback rating and return policy before committing to a purchase. If you need the item quickly, filter by "Buy It Now" to avoid the uncertainty of auctions. For used items, look closely at the condition description and photos — terms like "good", "very good" and "like new" can mean very different things depending on the seller.

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