Why a steel hardtail beats an aluminium one | Cotic Solaris Bronze vs Saracen Mantra Race LSL

Hardtails are a great winter option for those who want a mountain bike that’s easy to clean and maintain when the weather gets grim. For plenty of others, they’re simply a way of life.

There’s something deeply satisfying about bashing around with no rear suspension isolating you from what’s going on beneath you.

On a rigid frame, you can forget all about damping, spring weights, leverage curves, anti-squat and anti-rise numbers.

Put some power down, stomp hard and the bike charges forward with zero loss of efficiency.

This can be a real godsend in the colder months – who wants to take any more time than necessary getting from A to B when the thermometer is displaying single-digit temperatures?

As hardtail mountain bikes have evolved over the years, so have a few different schools of design thought.

Modern hardtails range from cross-country (XC) specific, with sharper angles and a more climbing-friendly bias through to fully slacked-out downhill bikes.

For the purposes of do-it-all riding or mucking about on though, the two main types are the all-day ‘trail’ hardtail, such as Cotic’s classic Solaris and the more descent-focused ‘hardcore’ hardtail, such as Saracen’s Mantra LSL.

Frame materials vary. While XC race hardtails are generally made from carbon fibre, other types tend to be constructed using either aluminium alloy (cheaper and often lighter) or chromoly steel (famed for its ‘zingy’ ride quality, if used well).

The nuances of material choice and design can make a surprising difference to the on-trail feel.

Because hardtail frames are cheaper to manufacture than a full-suspension chassis (with no pivots and linkages to worry about), you generally either pay less or get a better parts specification for your cash – sometimes both.

Of the two bikes here, the Mantra LSL Race has the more expensive parts, plus as we went to press, Saracen had taken £800 off its £2,799.99 RRP. That doesn’t necessarily mean it’s the best buy though.

With these bikes differing in terms of design intentions, wheel size, frame material and geometry, there’s a big variation in ride feel, which makes a huge difference on a hardtail.

Read on to find out which one bossed it for us on the trails…

Cotic Solaris Bronze Deore frame and suspension details

Saracen and Cotic’s design intentions for these bikes are slightly different. The Mantra LSL is focused slightly more on jumps and downhill, while the Solaris is more about all-day riding and smoothness.

This isn’t reflected only in the frame geometry and the kit they’re equipped with, but also the materials they’re made from. That means a steel frame on the Cotic and an aluminium one on the Saracen.

Cotic’s owner Cy Turner designs and develops his bikes in the Peak District, then outsources the manufacturing.

While some of his full-suspension bikes are made in Scotland, the Solaris frame is hand-welded in the Czech Republic.

Classic Reynolds 853 tubing is used for the front triangle, which includes the brand’s signature ovalised top tube, while 4130 chromoly appears elsewhere.

Behind the head badge, there’s a 44mm head tube with an external bottom cup and zero-stack upper for maximum bar-height adjustment.

The whole frame is pretty slim and slinky, but especially so at the wishbone stays, which are bridgeless and have curvy S-bends to afford the 29in wheels extra tyre clearance.

By the time you read this, the dropouts on new Solaris frames will have a Universal Derailleur Hanger/SRAM Transmission-compatible design, but my test bike still had a brand-specific hanger.

New frames will also come with gloss paint, in the same colour options (a whopping 18), which may work out better too, because the orange matt paint here was tough to clean.

Other details on this latest Solaris include a slightly lighter down tube than previously, which means the frame is only rated for a maximum of 130mm of fork travel.

You get loads of frame bosses for carrying bikepacking bags, or extra fluids for massive days out.

As a brief refresher, steel is heavier than aluminium, so you use less of it. This means the Cotic has a more traditional, skinny-tubed appearance, while the beefy, hydroformed tubes of Saracen’s rig are the kind of shapes and lines we’re used to seeing on full-suspension bikes these days.

Saracen Mantra Race LSL frame and suspension details

The Mantra LSL is made from 6-series alloy, which is custom-butted – that’s to say, different tube wall thicknesses are used where required for strength or stiffness.

It’s low-slung at the top tube, which keeps the frame out of the way of your knees, beefed-up around the head tube and seat-tower junctions, and the down tube curves to meet a reasonably low bottom bracket.

Frame details include funky box-shaped stays with the latest UDH interface. The back end has loads of mud clearance too. Unlike on the Solaris, all cables run internally for a cleaner look (but slightly less ease of maintenance).

There’s thin, rubberised frame protection under the down tube and on the driveside chainstay.

Cotic Solaris Bronze Deore geometry

Cotic has tweaked the Solaris’ geometry for 2024. The BB is a bit lower than previously (with a 55mm drop below the axles, using a 130mm fork) and the effective seat tube angle is marginally steeper too, for more efficient pedalling, at 73.1 degrees.

Up-front, the head angle is a relaxed 64.1 degrees, while the chainstays are a lengthy 444mm on all frames.

Reach figures span from 417.5mm to 489.5mm.

The brand has a new ‘C’ naming structure, with C1 the smallest and C5 the biggest. This brings slightly tighter gaps between sizes for a more precise fit and moves away from the old road-bike tradition of defining size by seat-tube length. I opted for the C3 size.

Saracen Mantra Race LSL geometry

Saracen’s ‘long, low and slack’ Mantra isn’t notably slacker, with a 64-degree head angle. However, it does feel lower – a sensation likely enhanced by the smaller rear wheel – with a 308mm BB height, and is most definitely longer.

Across the four sizes, reach grows from a relatively roomy 440mm to a massive 510mm.

These numbers are particularly long when you consider that on a hardtail, as the fork moves through its travel, it pulls your hands further away from your feet, increasing the effective reach (this effect is less pronounced on a full-suspension bike, where both ends compress simultaneously).

To counter this, some brands go shorter in the front triangle, so that once the fork is settled into its sag, you get the desired amount of cockpit room. Saracen doesn’t, so consider going down a size, unless you love a super-stable rig.

The size-medium test bike was roomy enough that our 6ft 4in (195cm) photoshoot model didn’t feel cramped.

The Mantra LSL is designed around a 140mm-travel fork, which is about as long as I’d ever go on a hardtail, because otherwise the bike’s dynamic geometry changes too much as it moves through its travel.

At 440mm, the chainstays are a few millimetres shorter than on the Cotic.

Cotic Solaris Bronze Deore spec details

Cotic’s philosophy of building up each bike in its Chesterfield HQ means you can spec yours pretty much as you fancy.

My test bike is based on the ‘Special Deal’ Bronze Deore package (£2,399), but came with matching Deore brakes instead of the SRAM Guide RSCs listed on Cotic's website, plus I added a dropper post (£200) and switched from WTB to Maxxis tyres (£40).

This change of tyres was significant, because the standard Verdict and Trail Boss tyres are much more aggressive and heavier than the Forekaster and Rekon setup here.

The lighter, faster tyres suited the Solaris’ personality much better, injecting a lot more rolling speed and get-up-and-go, while still being capable enough in technical terrain.

It’s pretty surprising what you can climb up with the low-profile Rekon, and you can lean it over to find bite in turns, unless it’s especially muddy or loose.

The wheels come from Shimano and use the brand’s cup-and-cone bearings. These MT620 hoops also match the Solaris well, boosting the slinky ride feel of the frame.

They’re smooth, fast and comfortable. However, ridden hard, they’re noticeably softer-feeling than the Saracen’s wheels.

The Cotic’s RockShox Revelation fork is a reasonable mid-range option, but not of the same quality as the brand’s Ultimate-level kit, and no match for the Fox 36 on the Mantra LSL.

Cotic fits its own bar, stem and grips. It’s all decent (if not very glamorous) kit, although the latter aren’t side-specific, so the rubber knurls on both grips twist to the same side of the bike, which feels a little odd.

The Deore two-piston brakes and gears are fine, although you may miss having the ability to multi-shift, if you're used to higher-tier kit.

There’s a bit of a flimsy feel to the shifter too, plus the brakes are nowhere near as powerful as the Mantra’s four-piston Deore XT stoppers.

Saracen Mantra Race LSL spec details

In terms of parts, Saracen’s bike clearly has the edge. You can’t expect a much better wheelset than tough DT Swiss EX 511 rims on Deore XT hubs – the exact kind of package many riders would specify from a custom wheel builder.

So long, that is, as you’re cool with maintaining cup-and-cone bearings (here with double contact seals), rather than running cartridge bearings until they die.

It’s also impossible to complain about the Deore XT drivetrain kit and brakes.

The same goes for the light-action KS LEV dropper post and the Fox 36 fork, which is one of the best MTB forks on the market, with stiff 36mm legs and superb, four-way adjustable GRIP2 damping.

Sadly, the same can’t be said about the Maxxis Minion tyre package. The bog-standard, dual-compound rubber looks out of place on such a quality build, doesn’t cut it in the wet and has far less grip than the triple-compound tyres on the Solaris, despite a more pointy and aggressive tread.

There’s less climbing traction, and, despite the proven block pattern, they feel nervy on greasy surfaces, roots and rocks.

There’s one other debatable kit choice – a Race Face Next R carbon bar, which is a bit stiff and solid, and amplifies the bike’s direct ride feel.

I’d suggest upgrading to one of the new breed of super-compliant bars, from the likes of OneUp or Reverse, which flex more under load.

Cotic Solaris Bronze Deore ride impressions

The prevailing feel from the Cotic is of a smooth and comfortable ride with a classic steel feel. That’s not to say it’s in any way boring or seems detached from the trail – the handling is very engaging.

The steering is reasonably light, and this brings more feel for the nuances of grip and precise front-tyre placement than on the slacked-out Saracen. It never feels too sharp or hard to control, and the front tyre doesn’t get pinged off-line too easily.

Rather, the Solaris has a well-balanced amount of feedback for the kind of riding you’ll be doing on a bike such as this.

Part of this ride character is likely due to the head angle, which is marginally steeper than on some hardtails, and also to the long chainstays.

These help keep your weight more centred, so there’s less sense of being pitched about in rougher sections, and there’s enough pressure through your hands and the front tyre’s contact patch to help you place the tyre edges precisely.

The longer stays also help to deliver tons of grip when climbing, aided by the suppleness in the frame and the grippier, slower-rebounding tyres.

So, while the Solaris is heavier than the Mantra LSL, it claws uphill and ascends better off-road.

Although it’s not targeted at rowdier trails and jumps (Cotic has the BFe for that), the Solaris still works really well for both.

The frame being so smooth means you get bounced around and beaten up far less on downhill tracks, and less fatigued riding it all day than you would on an aluminium hardtail such as the Saracen.

This difference in smoothness and comfort isn’t subtle either. Cotic’s bike is hugely calmer and less hectic-feeling on harder enduro tracks, to the extent that any potential benefits of the Mantra LSL’s longer reach go out of the window, offset by the destabilising jagged-bump interaction at the rear.

This may be amplified by the Solaris’ bigger 29in back tyre rolling over obstacles more smoothly.

On the first ride, it felt slightly harder to control the Cotic’s front wheel on really steep climbs.

However, removing a stem spacer and inching the saddle forward cured this trait.

Apart from the difference in braking power, this was just about the only thing to grumble about.