The competitively priced Marin Alpine Trail XR is designed to be a mountain bike that can handle the abuse of the all-day enduro rider without losing too much of that trail bike fun. Finding a bike that can blend performance in the 150/160mm category range isn’t nearly as hard as it was years ago thanks to competition pushing brands to develop better bikes year after year. What is hard however, is finding a capable bike that holds up AND doesn’t cost a fortune. Lucky for us the folks at Marin Bikes have been cranking out more capable bikes than ever and keeping an eye on the price tag while doing so. Let’s dig into the Marin Alpine Trail XR and see how it does when it’s not being raced against an Alpine Trail E2 eBike.
THE LAB
The new Marin Alpine Trail XR comes in at very reasonable $3,999 in the US and is offered in sizes Small to Extra Large to suit riders from 5’3” to 6’4”. The Series 4 6061 Aluminum frame features 150mm of travel controlled by Marin’s MultiTrac linkage driven single pivot suspension system. On this frame you get a Boost 148x12mm rear end, internal cable routing, and a 73mm threaded bottom bracket with some ISCG-05 tabs surrounding. Out front there is a 160mm RockShox Lyrik Ultimate with the Charger 2.1 Damper, giving you High and Low-speed compression, low speed rebound and the debonair air spring. Managing the 150mm of rear travel is a RockShox Super Deluxe Coil Ultimate RCT shock, with a three-position climb switch and independent low-speed compression and rebound adjustments.
Our size large test bike lands in with a reach of 480mm, a wheelbase of 1,256mm and a 632mm stack height. Reach figures have consistent 25mm jumps between sizes, save for the 35mm jump from Large to the XL’s length 515mm. All sizes come with 430mm chainstays, 35mm BB drop, 342mm BB height, 78-degree seat tube angle and a 63.5-degree headtube angle.
Every size comes with 29” Marin Aluminum Double Wall rims and Shimano hubs wrapped in 2.5” Maxxis Assegai tires with an EXO+ MAXX TERRA on the front and Double Down MAXX GRIP out back – tires that indicate the aggressive intentions of this machine. Both the drivetrain and brakes are covered by Shimano, with braking handled by their BR-MT420 4 Piston calipers and BL-M4100 levers, and a 12 speed XT derailleur matched up with a SLX shifter handling shifting duties across the SLX M7100 10-51t cassette. An FSA Gradient crankset with 32t direct mount ring handles power transfer. The cockpit features a 780mm wide, 20mm rise Race Face Affect R 35mm handlebar paired with a Aeffect R 50mm stem shod with Marin’s in house brand grips to match the Marin Speed Concept saddle. The X-Fusion Manic dropper on the medium and our size large lands at 150mm, while the small’s get a 125mm and the XL’s receive a 175mm version.
THE DIRT
When it comes to putting tires to the dirt the Alpine Trail XR is no stranger to rough terrain, but riders may also be surprised by its liveliness on mellower flow trails. The coil shock paired with a 160mm fork beckons for the rough stuff. Riding this at my local trail network (Tokul in Washington), there is a great mix of tight single track backed up by some technical jump lines, all of which were littered with gnarly braking bumps and completely blown out sections of trail thanks to nearly 50 days with no rain. The rear end ate up everything I could throw at it with the 450lb spring on the stiffer side of the right ballpark for me and ample progression to keep me off the bottom-out bumper. I took some time to fine tune the fork to get the most amount of traction possible as the trails lacked support in nearly every corner, but I found a sweet spot at 57 psi with 2 tokens for my 175lb weight.
At Tokul there is a particular section of a trail called Between 2 Ferns that has 4 back-to-back tight corners with wheel sized drops into the apex. On my personal bike this is one of the tougher sections in the whole area, but I found that the 430mm chainstays on the Alpine Trail XR really help get the bike to change direction in a snap, allowing me to come in and out of the corners significantly faster than I normally do. The Marin responds very well to your input for changing direction or altering your line. The bike has a very intuitive on-trail feel, jumping on it day-one I had a great feel for how it would react through corners and in the air. Balanced is a great way to describe the trail feel, not to poppy yet playful and not a suction cup to the ground but still tracking well through roots and rock gardens. The break-away point of traction is super controllable, I know this is partially due to having the grip-monster Assegai’s front and rear which is a great spec choice for those looking to ride technical terrain fast, but with not a lot of wheelbase growth through the travel it is easy to feel when that traction is about to give way to a slide. This gave a good amount of confidence to push the turns harder and play with the limits, leading to a grin-inducing time even on mellower trails.
When pointed up hill there is a noticeable amount of bob when you are hard on the pedals, and you begin to feel the 34.6lb total weight. For me this is not a big issue as I am the type of climber that will use the compression lever to mitigate any power loss, but it’s worth noting for lever-phobes or riders on undulating terrain. The flip side of this free rear end when pedaling is there is plenty of traction for short punchy and technical climbs. The seat tube angle is spot on for long climbs for me, giving a good balance between the wheels without going too extreme and upright. At 6’ 1” the large bike fit great, but the 150mm dropper was not cutting it for me. This is nothing new if you have read any of my previous reviews. Droppers are a hot topic for me, and I am not ashamed – we need to see longer units fitted! It’s a shame to waste the benefits of the low stand-overs by having the seatpost sticking high out the frame.
The build kit on this rig is nearly perfect in my eyes, for the money. The only negative I found was that the brakes seemed to be a little underpowered for the speed the XR begs you to generate. This could be improved cheaply by going from resin to metallic pads. While it will not make up for the calipers, it will for sure improve the bite you get once things heat up. Upgrading to some XT’s would be the ticket, perhaps with a 203mm rear rotor to boot. At Mt. Bachelor I did put a pretty sizeable dent in the rear wheel which resulted in a flat. This was not 100% the wheel’s issue as I was running only 26psi which is quite low for how rocky Bachelor is – I should have listened to Sourpatch and I paid the price with a long walk down to the lift. But it’s worth noting nonetheless, it’s safe to assume these wheels aren’t going to hold up quite as well as a higher end offering.
With so much focus placed on carbon frames these days it was refreshing to get on an aluminum frame. The trails I rode this bike on are trails I have ridden countless times and I can really tell a difference with components and frames. The bike was super compliant while not being mushy. The difference was subtle, but it was there, and offered an increase in comfort and grip on the off cambers that was very welcome. The weight penalty is well worth the cost savings in my eyes, I would much rather have a higher build spec than a carbon frame at this price point. It’s a rider’s bike for sure.
The Wolf’s Last Word
The Marin Alpine Trail XR delivers some serious bang for your buck, an all-around shredder that blends the gap between trail and enduro without many sacrifices along the way, save for the rear end’s pedal bob and a high overall weight. The suspension and geometry are spot on and leave little, if nothing at all, to be desired. Out of the box you can go smash your favorite local loop or head to the bike park for a weekend of lift served fun. 
Price: $3,999/£3450/€3955
Weight: 34.6 lbs
Website: Marinbikes.com
SPECIFICATIONS
CHASSIS
Frame: Series 4 6061 Aluminum Frame, 150mm
Fork: RockShox Lyrik Ultimate 160mm | 42mm Offset
Shock: RockShox Super Deluxe Coil Ultimate RCT|450lb|205x65mm
COCKPIT
Brakes: Shimano M4100/MT420 | 4 Pistons
Shifter: Shimano SLX M7100 | 12s | I-Spec EV
Handlebar: Race Face Aeffect R 35| B:35mm | R:15mm | W:780mm
Stem: Race Face Affect R 35| B:35mm | L:50mm
Saddle: Marin Speed Concept
Seatpost: X-Fusion Manic | 1x Composite Remote| Size S 125mm | M/ L 150mm | XL 175mm |30.9mm
WHEELS
Wheels: Marin Aluminum Double Wall | 29mm Inner | Shimano HB-MT510B/HF-MT410B Hubs
Front Tire: Maxxis Assegai 29×2.5” | MAXX TERRA | EXO+
Rear Tire: Maxxis Assegai 29×2.5” | MAXX GRIP | DoubleDown
DRIVETRAIN
Bottom Bracket: FSA MEGAEVO | 73mm BSA Threaded
Cassette: Shimano SLX M7100 | 12-Speed | 10-51T
Cranks: FSA Gradient | 32T
Derailleur: Shimano XT 12-Speed | SGS
We Dig
Suspension Package
On-trail predictability
Balanced handling
THE VALUE
We Don’t
Dropper post should be longer (Cole’s pet peeve)
Resin brake pads
Climbing efficiency
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