2021 Rocky Mountain Altitude Alloy vs 2021 Giant Reign Advanced Pro
The S is the Giant Reign Advanced Pro size closest to your 27.5 S Rocky Mountain Altitude Alloy. We match frame stack and reach. This is a geometry comparison, not a fit recommendation; stem, spacers, handlebars and saddle setup also affect your riding position.
What changes on the Giant Reign Advanced Pro
Compared with the Rocky Mountain Altitude Alloy in 27.5 S, the Giant Reign Advanced Pro in S places the top of the head tube 24 mm higher and 5 mm further back, relative to the bottom bracket. Its wheelbase is 20 mm longer, which can contribute to stability at speed.
- Frame stack
- +24 mm
- Higher front end
- Frame reach
- −5 mm
- Shorter frame reach
- Wheelbase
- +20 mm
- Longer: steadier at speed
- Head angle
- −0.2°
- About the same head angle
- Chainstays
- n/a
- One of the bikes has no number for this
The two frames
We can't draw these frames yet. The Rocky Mountain Altitude Alloy numbers we have for size 27.5 S are missing the chainstay length. The numbers below still compare.
Geometry side by side
| Measurement | Rocky Mountain Altitude Alloy 27.5 S | Giant Reign Advanced Pro S | Difference |
|---|---|---|---|
| Reach | 428 | 423 | −5 mm |
| Stack | 598 | 622 | +24 mm |
| Head tube angle | 64.8 | 64.6 | −0.2° |
| Seat tube angle | 75.8 | 76.4 | +0.6° |
| Effective top tube | not listed | 574 | |
| Chainstay length | not listed | 439 | |
| Wheelbase | 1171 | 1191 | +20 mm |
| BB drop | not listed | 27 | |
| Standover | not listed | 757 | |
| Seat tube length | not listed | 431 | |
| Head tube length | not listed | 100 |
Differences are the Giant Reign Advanced Pro minus the Rocky Mountain Altitude Alloy. Full charts: 2021 Rocky Mountain Altitude Alloy, 2021 Giant Reign Advanced Pro.
Where each sits in its class
Rocky Mountain Altitude AlloyGiant 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 AlloyAlloy 30 | Giant Reign Advanced ProAdvanced Pro 0 |
|---|---|---|
| Frame | Rocky Mountain FORM™ Alloy | Giant Reign |
| Fork | Marzocchi Z1 | Fox 38 Factory |
| Rear shock | Fox Float Performance | Fox DHX2 Factory |
| Shifter | Shimano Deore | Shimano XTR M9100 |
| Derailleur | Shimano Deore | Shimano XTR M9100 |
| Cassette | Shimano Deore XT | Shimano XTR M9100 |
| Chain | Shimano Deore M6100 | Shimano XTR |
| Crankset | Shimano Deore XT | Shimano XTR M9100 |
| Bottom bracket | Shimano SM-BBMT500 | not listed |
| Wheelset | Shimano MT410 | Giant TRX 0 |
| Tire | Maxxis Minion DHF, Maxxis Minion DHR II DD | Maxxis Assegai, Maxxis Minion DHR II DD |
| Brake | Shimano MT4120 | Shimano XTR M9120 |
| Rotor | Shimano SM-RT64 | Shimano XTR |
| Handlebar | Rocky Mountain AM | Giant Contact SLR |
| Stem | Rocky Mountain AM | Giant Contact SL |
| Grips | Ergon GE10 EVO | not listed |
| Headset | FSA Orbit 57E | not listed |
| Dropper post | Rocky Mountain Toonie Drop | not listed |
| Saddle | WTB Volt | Giant Romero SL |
| Seatpost | not listed | Fox Transfer Factory |
Know what is on every bike.
Add your bike to Quiver. Keep its parts, setup, and service history together, then share your build.
Explore the app
