Rockrider AM 100 review | Budget Mountain Bike of the Year winner

The Rockrider AM 100 exudes potential with its contemporary aesthetic and modern trail geometry, such as the 66-degree head angle.

The size-small bike I tested has a compact look, akin to a dirt jump bike, characterised by the clean line of the top tube merging seamlessly into the seatstays, and a low standover height. At first glance, expectations are high for this entry-level hardtail mountain bike.

Testing the size small revealed a noteworthy design choice – Rockrider has utilised the same frame for all sizes, using a 29er fork universally and adapting the S/M model with 27.5in wheels.

Critics may view keeping the frame design the same across the size range, rather than making a bespoke one for the 27.5in wheels, as a cost-saving measure. However, it offers distinct advantages if you’re buying the small or medium frames.

The low bottom bracket (measured in-house at 295mm) creates potential for pedal strikes, but it contribute to the bike's exceptional handling through the turns. This makes it a compelling choice for riders seeking agility and playfulness, which is what the AM 100 does best.

The frame design also gives you the flexibility to swap between 27.5in and 29in wheels on all sizes.

Rockrider AM 100 frame

Crafted from 6061 and 6013 triple-butted aluminium tubes, this aesthetically pleasing frame features a wide down tube, which is equipped with a single set of bottle bosses on the down tube for a water bottle. There's ample space for strapping bags and accessories inside the front triangle too.

The S-bend of the seatstays enables wider tyres to be fitted, while the rear bolt-thru axle adheres to the Boost standard of 12x148mm, opening up future upgrade compatibility.

Cables are routed externally and secured to guides bolted to the underside of the down tube.

From here, the rear brake cable runs under the chainstay, fastened with zip ties to welded cable guides. The dropper cable’s port is located low down on the back of the seat tube.

Rubber sleeves over the cables up front are designed to prevent rub on the head tube.

Rockrider AM 100 geometry

The S/M frames come equipped with nimble 27.5in wheels, while the L/XL sizes boast the efficiency of 29in wheels.

The AM 100 is designed around a 130mm-travel fork. The head angle is a trail-riding friendly 66 degrees, while the effective seat tube angle is 74 degrees.

This size small has a short 1,148mm wheelbase. Combined, these angles make the effective top tube long for a size small, at 600mm. The 410mm reach is short, but remains on the right side of playful thanks to the low standover, which leaves plenty of room for movement around the bike.

At only 295mm, the 27.5in-wheeled bike’s bottom bracket is particularly low, potentially boosting and improving handling.

Rockrider AM 100 specifications

The trail-ready AM 100 features a Shimano Deore 11-speed drivetrain with a 30t chainring and an 11-51t cassette for challenging ascents.

Equipped with a RockShox Judy Silver 130mm fork, it has adjustable rebound, an air spring and a lockout compression dial.

The Rockrider-branded dropper seatpost has 120mm of travel (small and medium), while Shimano’s MT200 brakes clamp 180mm front and 160mm rear rotors.

The Hutchinson Toro tyres are 2.25in wide.

Overall, the build is lightweight at 13.3kg, excluding pedals, and is lighter than the other budget mountain bikes on test by nearly 1kg.

Rockrider AM 100 ride impressions

I tested the Rockrider AM 100 at Scotland's Glentress Forest in a variety of conditions – including plenty of rain, mud and even snow.

From the initial setup ride, I felt at home on the Rockrider.

Details such as the shape of the riser bar, short stem and sharp Shimano brakes, that had the edge over the competition for power and urgency, played their part.

Rockrider AM 100 climbing performance

The 27.5in-wheeled AM 100 stood out with its impressive climbing performance, challenging the smooth-rolling efficiency of 29ers.

During my testing, I was pleasantly surprised by its relative ease in pedalling and maintaining speed on ascents. This was a notable departure from the perceived sluggishness and increased effort of other 27.5in bikes, such as the Calibre Line T3-27.

The fast-rolling Hutchinson Toro tyres, complemented by generous Shimano gearing (a 30t chainring and 11-51t cassette), and low weight combined for speedy ascending performance.

I had to push the saddle forward and angle it nose-down in the seat’s rails to improve climbing performance, despite its relatively orthodox 74-degree effective seat tube angle. Once set like this, leg power, efficiency and comfort were boosted.

This riding position combines well with a sweet-spot handlebar; its 25mm rise, 6-degree upsweep and 9-degree backsweep oriented my hands into a strong and comfortable position, undoubtedly contributing to it being the most comfortable hardtail to pedal in this Bike of the Year category.

The 433mm chainstays and 27.5in wheels facilitated effortless manuals, adding an element of fun to even the most mundane climbs.

Navigating fire roads with loose stones and potholes showcased the AM 100's frame compliance, effectively damping chatter and providing a smoother ride than its stiffer counterparts.

The experience was notably distinct when ridden consecutively with other hardtails, highlighting the AM 100's forgiving nature on rough terrains.

Despite concerns about the smaller wheel size being prone to hooking up on roots and rocks, the frame's compliance played a crucial role in offsetting the jarring impact, ensuring a well-balanced ride.

Rockrider AM 100 descending performance

The Rockrider AM 100 demonstrated commendable performance during initial rides on smooth trail-centre tracks with turns and jumps.

The optimum climbing position was matched with a first-class standing stance when pointing downhill.

The AM 100 is one of those bikes that inspires confidence from the first trail. The Shimano MT200 brakes were swift to bed in and proved their worth in dry conditions on blue and green-graded trails.

Upping the ante and taking the AM 100 onto rooty off-piste trails in wet, muddy conditions, the bike could benefit from either a larger rotor on the front brake or more urgent, powerful brakes.

That being said, with a little more consideration for speed when approaching rooty features and turns in the trail, the brakes were adequate for a moderately paced run.

If you’re heavy on the brakes, we’d recommend upgrading to a set of the best mountain bike brakes when funds permit.

One of the biggest factors contributing to the AM 100's confidence-inspiring ride is the 295mm bottom bracket height, which is 20mm lower than comparable bikes such as the Calibre Line T3-27 and Merida Big Trail 400.

This lower height effectively eliminated the 'perched' feeling associated with those bikes.

The AM 100's 'slammed' feel, coupled with the grippy Hutchinson Toro tread pattern, slack head angle, and well-proportioned wheelbase and reach, solidified its reputation as a capable hardtail for trail riding.

However, the smaller wheels on the AM 100 presented a drawback on extended, technical trails, exhibiting a tendency to stall over roots and rocks when compared to 29er counterparts.

The frame's compliance, though, offered some compensation, that was particularly noticeable during ascents.

On a less positive note, there was a distracting knocking on rooty trails and fire roads, which I eventually traced back to the fork's bushings.

An initial fork setup with 25 per cent sag resulted in easily blowing through the travel in berms and landing small drops.

Being unable to fit volume reducers in the Rockshox Judy Silver, my only option was to add pressure to the fork, eventually settling on 13 per cent sag.

Despite the increase in pressure, both mid-stroke support and bottom-out resistance remained somewhat lacking, although this didn’t detract significantly from the overall performance.

How does the Rockrider AM 100 compare to the Calibre Line T2 27?

If you’re on the hunt for a 27.5in-wheeled bike, you’ll do well to have the AM 100 and Calibre Line T2 on your shortlist.

The Line T2 boasts a slightly better spec, notably a smooth 125mm-travel KS Rage-i dropper, compared to the Rockrider’s own-brand post.

The Rockrider sports Shimano gears, while the Calibre has a SRAM NX 11-speed drivetrain. SRAM’s Level T brakes are fitted, as opposed to the Rockrider’s Shimanos, although both have 180mm and 160mm rotors front and rear respectively. While both sets of brakes are equally powerful and reliable, neither are top performers.

A wider gear range on the Rockrider (30t chainring, 11-51t cassette versus the Calibre’s 32t, 11-42t) puts it at a distinct advantage over the Line for me.

Despite Calibre's Rockshox FS Recon Silver RL fork, with an extra 20mm of travel, it was the Rockrider that offered a more plush, forgiving ride on rough terrain.

The planted feel and control on turns and steep trails, coupled with a £200 saving, makes the AM 100 one of the best budget hardtails on offer.

Rockrider AM 100 bottom line

The AM 100 is a standout hardtail that offers impressive performance and style at an affordable price. It excelled on the climbs, despite the small wheels, while its nimble handling and trail performance impressed.

In the entry-level category, the components may not be as high-end, but the AM 100's serve their purpose effectively.

The lightweight frame provides a solid foundation for future upgrades to enhance performance and further reduce its already low weight.

Overall, the AM 100 is a smart purchase for those looking for a capable, nimble and playful hardtail without breaking the bank. For these reasons, the AM 100 is BikeRadar’s 2024 Budget Mountain Bike of the Year.