reynolds 853

853 steel is Reynolds’ premium grade of ferrous steel. Renowned for producing light, stiff, yet supple frames, 853 is the frame builder’s choice when only the best will do.

Available in a range of lengths up to 850mm, diameters up to 44.2mm and a wide range of butt profiles 853 finds a home in the rowdiest of mountain bikes and the most responsive of road and gravel bikes.

853 is an air-hardening steel. The benefits of this are particularly noticeable in the weld area, where, unlike conventional steel alloys, strength can actually increase after cooling in air immediately after welding. 853 is heat-treated to give high strength and damage resistance, and the steel properties allow thin walls to be used so that lower-weight but fatigue-resistant structures can be made.

Why Reynolds 853 steel works:

UTS: 1250-1400 MPa, density 7.78 gm/cc

The chemistry includes carbon, manganese, chrome, molybdenum, silicon, and copper.

The interaction between the alloys results in a fine grain structure that forms with air-cooling without the traditional “quenching” (fast cooling in water or oil) process. High strength from bainitic phase steel after a series of cold-working operations.

Additionally, heat treatment to the 853 specification raises the yield strength for the entire tube, increasing dent and impact resistance.

Reynolds has two specific variations in 853 steel:

a) ProTeam: the thinnest wall tubes made for road bikes

b) DZB: for Double Zone butted tubes, which are particularly suitable for ATB and 29er frames.

This helps reduce or eliminate the gussets normally required to pass the stringent EN fatigue testing standards.

For more on the difference between 853, ProTeam and DZB, watch this 80-second video summary:


How you would use it:

This heat-treated version of 631 is the pinnacle of Reynolds ferrous steels.
It allows frame builders to make very strong, stiff frames with a low frame weight
It can be used in a pure 853 frame to produce a very stiff, light frame with excellent performance for a pure road bike.

One of the most common mix-and-match combinations is an 853 front triangle with chain and seat stays in 631. This gives the ‘goldilocks’ combination of a stiff cockpit with the ability to fine-tune the ride through the chain and seat stays for a super smooth ride with excellent pedalling performance.

This combination is popular across road, especially 4 season and endurance bikes, gravel, and MTB. An 853 front triangle for a full-suspension mountain bike provides a stable platform for managing the high suspension loads from jumping. At the XC end, it gives a rigid but light pedalling platform with all the feedback you need from the rear wheel.

Note that builders can also select from a choice of over 500 tube variations to suit their specific customer preferences, providing a high degree of design flexibility using a “mix-and-match” approach instead of having to use a pre-selected frame kit.

Learn More

Click here to download a metal alloys comparison (extract) PDF for designers.