How to Choose Mountain Bikes
Rocky Mountain Altitude Alloy 50 Mountain Bike
$4,799.00
Members get an est. $479.90 in rewards
Own weekend rides or take lead in a race with the Rocky Mountain Altitude Alloy 50 mountain bike. It's purpose-built to go fast and conquer steep trails with the RIDE-4™ adjustment system.
Key Details
Wheel Size
S: 27.5 inches
M: 29 inches
L: 29 inches
XL: 29 inches
Fork Travel
170 millimeters
Number of Gears
12 gear(s)
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- LC2R™ (Low Center Counter Rotating) suspension system is the Rocky Mountain take on a virtual pivot suspension design
- LC2R delivers a smooth and predictable ride on challenging terrain
- Reach adjust headset lets you fine-tune your ride with center and +/-5 mm offset options
- The RIDE-4™ adjustment system allows riders to quickly fine-tune their geometry with a single Allen key: 4 configurations are possible thanks to 1 rotating chip
- 29 in./MX: You can mullet M–XL frame sizes via built-in flip chip; no need to buy a separate link or mount
- Size Specific Tune ensures that riders of all sizes get the right balance of small-bump compliance, mid-stroke support and end-stroke progressiveness
- The Rocky Mountain team does custom shock tunes based on real-world field testing and adjusts each tune for specific frame sizes
- Size-specific chainstay lengths offer a balanced ride across all frame sizes
- FORM™ tubesets utilize premium materials to meet strict requirements
- Each FORM tube that Rocky Mountain creates is engineered for its specific purpose within the frame, ensuring optimized strength, weight and ride quality
- NOTE: Specs and images are subject to change based on component availability
Imported.
This bike comes with Coast to Coast Support, which includes:
New bikes go through a normal break-in period, after which they should be readjusted. All bicycles sold at REI include free adjustments for one year after purchase date—as many times as you need. Included: derailleur and brake adjustments, lateral wheel truing, hub and headset bearing adjustments, tire inflation and chain lubrication. Not included: replacement or installation of new components or accessories, any other services. Call your local REI Co-op Bike Shop for more information.
View all Rocky Mountain Full-Suspension Mountain Bikes- 1 year of free adjustments (see more below)
- In-store bike assembly
- Pickup in store or curbside
- Bike experts available at 170+ bike shops
- 20% off shop services
- Free tubes with purchase of flat tire repair (Co-op Cycles brand tubes only; tube must be installed at time of purchase)
New bikes go through a normal break-in period, after which they should be readjusted. All bicycles sold at REI include free adjustments for one year after purchase date—as many times as you need. Included: derailleur and brake adjustments, lateral wheel truing, hub and headset bearing adjustments, tire inflation and chain lubrication. Not included: replacement or installation of new components or accessories, any other services. Call your local REI Co-op Bike Shop for more information.
| Best Use | Mountain Biking |
|---|---|
| Frame | FORM alloy |
| Step-Through | No |
| Mountain Bike Style | All-mountain |
| Bike Suspension | Full Suspension |
| Fork | Fox 38 Float EVOL GRIP Performance Series 170 mm; 27.5: 37 mm offset; 29: 44 mm offset |
| Fork Travel | 170 millimeters |
| Rear Shock | Fox Float X Performance; sealed bearing eyelet; 40 x 10 mm F hardware; S: 210 x 55 mm; M-XL: 230 x 60 mm |
| Crankset | Race Face Aeffect Cinch; 32T; 24 mm spindle; S: 165 mm; MD-XL: 170 mm |
| Bottom Bracket | Shimano Threaded BBMT501-B |
| Shifters | Shimano SLX |
| Rear Derailleur | Shimano XT |
| Rear Cogs | Shimano Deore 10-51T 12-speed |
| Number of Gears | 12 gear(s) |
| Brake Type | Hydraulic Disc Brake |
| Brakes | Shimano SLX Trail 4 piston, metal pads |
| Brake Levers | Shimano SLX Trail 4 piston, metal pads |
| Rims | WTB ST i30 TOUGH TCS 2.0; 32H; tubeless setup, sealant included |
| Front Hub | Novatec D791SB Sealed Boost 15 mm |
| Rear Hub | Shimano XT Boost 148 mm |
| Wheel Size | S: 27.5 inches M: 29 inches L: 29 inches XL: 29 inches |
| Tires | Front: Maxxis Assegai 2.5 WT 3C MaxxGrip EXO+ tubeless ready; rear: Maxxis Minion DHR II 2.4 WT 3C MaxxTerra DD Tubeless ready; tubeless set up, sealant included |
| Tire Width | 2.5 inches 2.4 inches |
| Handlebar Shape | Flat Bar |
| Handlebar | Rocky Mountain AM; 780 mm width; 38 mm rise; 9 degrees backsweep; 5 degrees upsweep; 35 clamp |
| Stem | Rocky Mountain 35 AM; 5 deg. rise; all sizes: 40 mm |
| Seat Post | X Fusion Manic Composite 30.9 mm; S: 150 mm; M: 170 mm; L-XL: 200 mm |
| Dropper Post | Yes |
| Saddle | WTB Solano Fusion Form 142, chromoly rails |
| Pedals | Not included |
| Headset | FSA ZS56/66 reach adjust; 0 mm cups installed; +/- 5 mm cups included; sealed stainless 36 deg. x 45 deg. bearings; 30.2 mm x 41 mm x 7.1 mm upper; 40 mm x 51.8 mm x 7.5 mm lower; 1.5 in. Crown Race |
| Chain | Shimano M6100 |
| Weight | 36 lbs. 14 oz. |
| Bike Weight | Bike weight is based on median size, as sold, or the average of two median sizes. |
| Gender | Unisex |
Rocky Mountain Bikes (245871)
| S | M | L | XL | |
|---|---|---|---|---|
| Height Range | 5'0" - 5'6" | 5'4" - 5'10" | 5'8" - 6'2" | 6'0" - 6'6" |
| Reach | 424 | 450 | 475 | 505 |
| Stack | 599 | 630 | 639 | 653 |
| Effective Top Tube | 553 | 584 | 610 | 642 |
| Seat Tube Center-Top | 365 | 410 | 440 | 470 |
| Standover Height | 760 | 792 | 798 | 809 |
| Head Tube Length | 100 | 105 | 115 | 130 |
| Head Tube Angle (degrees) | 63 | 77 | 77 | 77 |
| Seat Tube Angle (degrees) | 77 | 410 | 440 | 470 |
| Wheelbase | 1189 | 1244 | 1283 | 1319 |
| Chainstay | 430 | 440 | 450 | 450 |
Sizing Notes
Measurements are stated in millimeters unless otherwise indicated.
How we measure bikes
- Standover Height Standover Height is a measurement from the ground to the top of the top tube, measured at the midpoint of the top tube.
- Reach Reach is the horizontal distance from the center of the cranks to the center of the head tube, measured at head tube level.
- Stack Stack is the vertical distance from the center of the cranks to the center of the head tube, measured to the top of the head tube.
- Effective Top Tube Effective top tube is the distance from the center of the head tube to the center of the seat tube/seat post, measured parallel to the ground.
- Seat Tube Center to Top Seat Tube length is the measurement of the seat tube, from the center of the cranks to the top of the seat tube.
- Head Tube Length Head Tube Length is measured from the bottom to the top of the head tube.
- Head Tube Angle Head Tube Angle is the acute angle between the head tube and the ground (measured towards the rear of the bike)
- Seat Tube Angle Seat Tube Angle is the acute angle between the seat tube and the ground (measured towards the rear of the bike).
- Bottom Bracket Height Bottom Bracket Height is a measurement taken vertically from the ground up to the center of the cranks.
- Wheelbase Wheelbase is the measurement from the center of the front axle to the center of the rear axle.
- Chainstay Length Chainstay Length is the measurement from the center of the cranks to the center of the rear axle.
- Fork Offset Fork Offset, or rake, is the distance from the front axle to a line drawn parallel to the center of the head tube or steering axis.
