Breezer Thunder: A Steel Trail Bike for Mountain Touring
The Breezer Thunder combines a steel trail frame, a 130 mm suspension fork and a twelve-speed transmission with luggage attachment points. That makes it worth considering for riders whose mountain-bike plans include longer journeys as well as singletrack. It also makes identifying the generation important: an older Thunder Pro photograph does not describe the same complete build.
Where the Breezer Thunder fits
Breezer describes the documented model as intended for singletrack and mountain touring. Its frame entry names 4130 butted chromoly steel, a tapered head tube and 148 mm rear spacing. These are concrete construction details, rather than evidence that steel automatically makes a bicycle more comfortable or durable than every alternative.
The manufacturer's equipment list pairs that chassis with a Marzocchi Bomber Z2 fork. Its 130 mm travel sits alongside a wide 780 mm handlebar and a KS Rage I dropper post. Together those entries describe a trail-oriented complete bicycle; they do not supply a personal ride test or permission for every jump and bike-park route.
A transmission with a broad listed spread
A Shimano Deore Shadow Plus twelve-speed rear derailleur and Rapid Fire Plus shifter accompany a Deore 10–51T cassette. The table also names a KMC twelve-speed chain. Calling this a twelve-speed Deore-equipped build is useful, but describing every component as Shimano would overlook that chain entry.
Equipment for a longer day out
TRP Slate EVO hydraulic disc brakes have listed 180 mm rotors at both ends. Dropper travel changes with frame size: 100 mm on Small, 125 mm on Medium and Large, and 150 mm on XL. These differences deserve attention when comparing two sizes, even though both carry the Thunder name.
The frame specification includes bottle, bento, three-pack and rear-rack attachment points. They broaden the packing possibilities without establishing the permitted weight of a loaded bicycle. Likewise, the published 34.2 lb weight belongs specifically to a Large; it is not a frame-only measurement or a figure for every size.
Recognise the older Thunder Pro
The historical photograph shows ThunderPRO lettering and several front chainrings. Its supplied title says 2010, while its capture date is November 2009. Those details explain why an image search can produce a bicycle that looks quite different from the current specification, without establishing its old factory materials or component standards.
The Heavy Skies model is a Breezer Thunder. When considering it for a longer off-road journey, look at the present build’s gearing, dropper travel and attachment provisions together. The blue-white ThunderPRO in the older picture belongs to a different historical reference.
FAQ
What frame material does the documented Thunder use?
The manufacturer specifies 4130 butted chromoly steel for this model.
Is the published weight the same for every size?
No. The 34.2 lb reference is explicitly labelled Size Large.
Does the old photograph show this exact build?
No. It shows a dated ThunderPRO, whose current-edition identity is unverified.
The Breezer background guide places this mountain-bike lineage beside the company’s everyday bicycles. Use the Breezer topic to keep those different riding purposes in view.
Sources: manufacturer specifications (https://www.breezerbikes.com/products/thunder-25).
Photograph credits and permissions
Photograph 1
Original title: 2010 Breezer Thunder
Creator: Richard Masoner / Cyclelicious; creator URI: https://www.flickr.com/photos/bike/; creator-requested attribution URI: http://www.cyclelicio.us/; creator profile: https://www.flickr.com/people/bike/
Original source URI: https://www.flickr.com/photos/bike/4079688150
License / permission: CC BY-SA 2.0
License / permission URI: https://creativecommons.org/licenses/by-sa/2.0/
Modification notice: Original source-hosted JPEG retained unchanged by this publisher. Earlier source modifications are unassessed.
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