2021 Rocky Mountain Altitude Alloy (27.5) vs 2021 Giant Reign Advanced Pro
The Giant Reign Advanced Pro size closest to your M is the M. Compare the M instead
What changes on the Giant Reign Advanced Pro
Compared with the Rocky Mountain Altitude Alloy (27.5) in M, the Giant Reign Advanced Pro in S places the top of the head tube 15 mm higher and 30 mm further back, relative to the bottom bracket. Its wheelbase is 9 mm shorter, which can contribute to quicker direction changes.
- Frame stack
- +15 mm
- Higher front end
- Frame reach
- −30 mm
- Shorter frame reach
- Wheelbase
- −9 mm
- Shorter: quicker to change direction
- Head angle
- −0.2°
- About the same head angle
- Chainstays
- +11 mm
- Longer: more planted
The two frames
Rocky Mountain Altitude Alloy (27.5), MGiant Reign Advanced Pro, SDrawn to scale and lined up at the bottom bracket.
Geometry side by side
| Measurement | Rocky Mountain Altitude Alloy (27.5) M | Giant Reign Advanced Pro S | Difference |
|---|---|---|---|
| Reach | 453 | 423 | −30 mm |
| Stack | 607 | 622 | +15 mm |
| Head tube angle | 64.8 | 64.6 | −0.2° |
| Seat tube angle | 75.8 | 76.4 | +0.6° |
| Effective top tube | 606 | 574 | −32 mm |
| Chainstay length | 428 | 439 | +11 mm |
| Wheelbase | 1200 | 1191 | −9 mm |
| BB drop | 15 | 27 | +12 mm |
| Standover | 802 | 757 | −45 mm |
| Seat tube length | 420 | 431 | +11 mm |
| Head tube length | 110 | 100 | −10 mm |
Differences are the Giant Reign Advanced Pro minus the Rocky Mountain Altitude Alloy (27.5). Full charts: 2021 Rocky Mountain Altitude Alloy (27.5), 2021 Giant Reign Advanced Pro.
Where each sits in its class
Rocky Mountain Altitude Alloy (27.5)Giant Reign Advanced Pro
Each bike is ranked against the other enduro bikes on Quiver, on frame geometry alone. Not your hand position or ride feel.
What each ships with
The stock build of each bike's first listed trim. Parts that match are dimmed.
| Part | Rocky Mountain Altitude Alloy (27.5)Alloy 50 (27.5) | Giant Reign Advanced ProAdvanced Pro 0 |
|---|---|---|
| Fork | Fox 36 Performance | Fox 38 Factory |
| Rear shock | Fox DPX2 Performance | Fox DHX2 Factory |
| Chain | Shimano Deore M6100 | Shimano XTR |
| Crankset | Race Face Aeffect Cinch | Shimano XTR M9100 |
| Tire | Maxxis Assegai, Maxxis Minion DHR II | Maxxis Assegai, Maxxis Minion DHR II DD |
| Hub | Rocky Mountain Sealed Boost, DT Swiss 370 | not listed |
| Rim | WTB ST i30 | not listed |
| Rotor | Shimano SM-RT66 | Shimano XTR |
| Dropper post | Race Face Aeffect R | not listed |
| Frame | not listed | Giant Reign |
| Shifter | not listed | Shimano XTR M9100 |
| Derailleur | not listed | Shimano XTR M9100 |
| Cassette | not listed | Shimano XTR M9100 |
| Wheelset | not listed | Giant TRX 0 |
| Brake | not listed | Shimano XTR M9120 |
| Handlebar | not listed | Giant Contact SLR |
| Stem | not listed | Giant Contact SL |
| Seatpost | not listed | Fox Transfer Factory |
| Saddle | not listed | Giant Romero SL |
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