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Verdict: 
The Nitro SL uses a race-proven formula, offering speed and long-distance comfort
Weight: 
7,700g
Merlin Nitro SL 2017
9 10

Merlin Cycles has been offering its own brand of bikes for a while, and the Nitro SL is an excellent addition thanks to its balance of speed, light weight and comfort. A lot of companies get slated for rebadging off-the-shelf carbon fibre models but Merlin has chosen well with this Belgian beauty.

It's no secret that Merlin has opted for Ridley's Helium SL frameset as its base for the Nitro SL. With the Helium SL being upgraded to the SLX, the Nitro SL could be considered outdated tech, but it is far from it.

The frameset holds its head up high and delivers across the board against the competition.

Ride

The ride is sublime, that balance of stiffness and the way it deals with the bumps in the road is a masterclass in carbon fibre layup and tube design. The Nitro SL just seems to take everything in its stride with regard to road surface imperfections.

At 7.7kg, a smidge under 17lb if you're that way inclined, the Merlin is light and very responsive. It climbs way better than you'd expect and acceleration is very impressive thanks to that very stiff bottom bracket area.

Merlin Nitro SL - riding 2.jpg

Merlin Nitro SL - riding 2.jpg

The whole package works so well together that even though you could save a chunk of weight with a carbon wheel upgrade, one that the Nitro SL would relish, as a straight-out-of-the-box setup the Merlin is hard to knock.

Even though the Nitro SL is a race machine with its 1:41 stack to reach ratio (stack and reach are the vertical and horizontal measurements from the centre of the bottom bracket to the top of the head tube) plus aggressive seat and head tube angles, its handling is a little less direct than you'd expect. It lacks that real razor sharpness of a lot of peloton-ready frames when things get really technical in the bends, but this does mean that it makes for a great long-distance bike.

Merlin Nitro SL.jpg

Merlin Nitro SL.jpg

When fatigue kicks in, for instance on an all-day training ride or when pushing yourself on a challenging sportive, a twitchy handling bike becomes more of a chore than a benefit.

That isn't to say the Merlin is the soft option – the whole thing is pretty rigid, and thanks to the tapered head tube things are tight up the front end when it comes to steering or heavy braking.

Merlin Nitro SL - head tube badge.jpg

Merlin Nitro SL - head tube badge.jpg

The biggest highlight for me was the way that the Merlin just got on with the job. There doesn't seem to be a compromise with its performance: you get on it, pedal like a mad man, and it delivers. You'll be amazed by how much ground you'll cover with relatively little in the way of effort.

Merlin Nitro SL - riding 3.jpg

Merlin Nitro SL - riding 3.jpg

Frame and fork

The Nitro SL comes adorned with a UCI approved sticker, which means you can ride this bike in any of the governing body's sanctioned events should you so wish. All of this is because just 12 months ago this frame was being powered by the legs of the pros – not something you'd normally expect for less than two grand.

Merlin Nitro SL - UCI sticker.jpg

Merlin Nitro SL - UCI sticker.jpg

With a claimed frame weight of just 750g, the Nitro SL frame is up there with the lightest, and just shows how far you could go with the build; full Di2 and some super duper lightweight carbon rims for instance wouldn't embarrass this frame in feel or looks.

Manufactured from 24/30 ton carbon fibre, a figure related to the tensile strength of the fibres, the various tube profiles make for a very stiff frame. As I mentioned earlier, you get a tapered head tube for stiffness plus the down tube has a square section, oversized profile to tame the forces at both ends.

Merlin Nitro SL - down tube.jpg

Merlin Nitro SL - down tube.jpg

With all the woes of press fit bottom brackets and their creaking issues because of poor tolerances, it's good to see Merlin has opted for a threaded bottom bracket setup. Okay, you sacrifice a small amount of rigidity by going narrower at the BB, but unless you're riding two differing frames side by side it's difficult to detect.

Merlin Nitro SL - bottom bracket.jpg

Merlin Nitro SL - bottom bracket.jpg

The chainstays aren't the largest we've seen, but again they deliver what they need to, while the seatstays are narrow for some shock absorption. It all works together, as the Merlin delivers both in out-of-the-saddle sprints and those seated, dig-in, get-it-done efforts.

Merlin Nitro SL - chain stay detail.jpg

Merlin Nitro SL - chain stay detail.jpg

In terms of cabling, the gears run internally through the frame, which means both electronic and wired groupsets will work without spoiling the lines. The brake cables run on the outside and, to be honest, are barely noticeable.

Merlin Nitro SL - cable route 2.jpg

Merlin Nitro SL - cable route 2.jpg

One good thing to note is the inclusion of a replaceable dropout on the drive side; it's quite commonplace these days, and it's always good to know you won't write off an entire frame from a small crash.

Finishing kit

The Nitro SL comes with a full Shimano Ultegra 6800 groupset, which is about right for this price point, but it is good to see Merlin hasn't scrimped anywhere by subbing out the crankset or brakes to another manufacturer.

Merlin Nitro SL - front brake.jpg

Merlin Nitro SL - front brake.jpg

The setup we've got here is a 52/36 semi-compact chainset which, when paired with the 11-28t, 11-speed cassette, gives a sporty range of gears ideal for this style of bike.

Merlin Nitro SL - crank.jpg

Merlin Nitro SL - crank.jpg

Ultegra's shifting is top notch, being only slightly less precise than Dura-Ace for a fraction of the price, and the braking power from the callipers is massively efficient in all but the wettest of conditions. The Ultegra slate finish also matches the frameset's paintjob too. Nice.

Merlin Nitro SL - bar and shifter 2.jpg

Merlin Nitro SL - bar and shifter 2.jpg

Fulcrum's Quattro LG is a decent wheelset too, specced off the shelf with 35mm deep alloy rims and a solid build. They roll really well and even with their claimed 1,725g weight they don't feel sluggish on a bike of this calibre. They'll take a huge amount of abuse, so I'd say they are only worth upgrading if you want to really go for the ultimate weight saver build

Merlin Nitro SL - rim.jpg

Merlin Nitro SL - rim.jpg

The same could be said for the tyres. Continental's Ultra Sports are far from the grippiest or most supple of rubber but they do the job and offer plenty of durability too.

4ZA is Ridley's in-house brand and features here as the bar, stem and seatpost. They're all alloy, but they do the job and to upgrade them would only really be a vanity exercise. The compact drop of the bar will suit most, offering plenty of hand positions.

Merlin Nitro SL - bar and shifter.jpg

Merlin Nitro SL - bar and shifter.jpg

Value

There are a lot of Ultegra-equipped carbon fibre bikes out there for less than the two grand rrp of the Nitro SL, but this one has pedigree. It's pro-level peloton-proven, and while the badge snobs may struggle to agree, it's one hell of an accomplished frameset.

> Buyer's Guide: 10 of the best Ultegra-equipped road bikes

There are others out there mind: the Canyon Ultimate CF SL 9.0 for instance, which when you add on postage and packaging comes in at £1,945 with a very similar build.

But, get this, at the moment Merlin is offering the Nitro SL for £1,749.95 and that includes a set of pedals – Ultegra for instance – plus a pair of Mavic Ksyrium Ultimate II shoes, which range from £90 to £120ish on t'internet. The Merlin looks like a bit of a steal.

Verdict

The Nitro SL uses a race-proven formula, offering speed and long-distance comfort

road.cc test report

Make and model: Merlin Nitro SL

Size tested: 54cm

About the bike

State the frame and fork material and method of construction. List the components used to build up the bike.

Frame: 24 Ton High Modulus Carbon

Fork: Carbon Blades with Carbon Steerer

Wheels: Fulcrum Racing Quattro LG wheelset

Tyres: Continental Ultra Sport II 25mm folding bead

Chainset: Shimano Ultegra 6800 52/36T

Front Derailleur: Shimano Ultegra 6800 or Di2

Rear Derailleur: Shimano Ultegra 6800 or Di2

Gear/Brake Levers: Shimano Ultegra 6800 or Di2

Brake calipers: Shimano Ultegra 6800

Cassette: Shimano 105 5800

Handlebars: 4ZA Stratos

Stem: 4ZA Stratos

Seatpost: 4ZA Stratos

Saddle: San Marco Ponza

Weight: 7.70kg (Medium)

Maxium Rider Weight: 95kg

Tell us what the bike is for, and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about the bike?

Merlin says: "Superlight race bike weighing a helium light 7.70kg. The oversized tube shape is engineered with the use of extremely high modulus carbon. This results in a very light frame, without compromising stiffness. The dual purpose internal cable routing uses the same holes for mechanical and electronic shifting, resulting in a very clean design. Flex seat stays increase vertical compliance for additional comfort, without reducing lateral stiffness.

"This is without a doubt our best looking Merlin road bike, coupled up with the bomb proof Shimano Ultegra 6800 11 speed group and Fulcrum's Racing Quattro Wheels make this an epic value for money top racer! 4ZA take care of the rest of the finishing kit with components from their Stratos range."

The Merlin Nitro SL is a pro-level-proven frame and it is impressive to ride.

Frame and fork

Overall rating for frame and fork
 
9/10

Tell us about the materials used in the frame and fork?

The Merlin is constructed from 24 ton high modulus carbon fibre and includes a full carbon fibre fork, aluminium dropouts aside.

Tell us about the geometry of the frame and fork?

Full details are here: https://www.merlincycles.com/resources/images/Merlin%20Nitro%20SL_GEO_ne...

Things are pretty aggressive, as you'd expect from a full-on race bike.

How was the bike in terms of height and reach? How did it compare to other bikes of the same stated size?

Stack of 545mm and reach of 385mm is pretty typical for a bike in a 54cm size, and the ratio of 1:41 is what you'd expect for a race bike.

Riding the bike

Was the bike comfortable to ride? Tell us how you felt about the ride quality.

Yes, supremely so.

Did the bike feel stiff in the right places? Did any part of the bike feel too stiff or too flexible?

Yes, it delivers on all levels without being overly harsh.

How did the bike transfer power? Did it feel efficient?

Power transfer is impressive throughout the frame.

Was there any toe-clip overlap with the front wheel? If so, was it a problem?

Yes, but no real issue.

How would you describe the steering? Was it lively, neutral or unresponsive? The lively side of neutral.

Tell us some more about the handling. How did the bike feel overall? Did it do particular things well or badly?

The handling is quick without being overly twitchy. I've ridden more 'point and shoot' kind of bikes but the Merlin doesn't lack precision.

Which components had the most effect (good or bad) on the bike's comfort? would you recommend any changes?

It is a good all-round package that works together.

Which components had the most effect (good or bad) on the bike's stiffness? would you recommend any changes?

I liked the 4ZA components as they didn't offer any flex.

Which components had the most effect (good or bad) on the bike's efficiency? would you recommend any changes?

You get a little bit of an aero boost from the Fulcrum wheels.

Rate the bike for efficiency of power transfer:
 
9/10
Rate the bike for acceleration:
 
9/10
Rate the bike for sprinting:
 
8/10
Rate the bike for high speed stability:
 
8/10
Rate the bike for cruising speed stability:
 
9/10
Rate the bike for low speed stability:
 
8/10
Rate the bike for flat cornering:
 
8/10
Rate the bike for cornering on descents:
 
8/10
Rate the bike for climbing:
 
9/10

The drivetrain

Rate the drivetrain for performance:
 
9/10
Rate the drivetrain for durability:
 
8/10
Rate the drivetrain for weight:
 
8/10
Rate the drivetrain for value:
 
9/10

Tell us some more about the drivetrain. Anything you particularly did or didn't like? Any components which didn't work well together?

Shimano Ultegra 6800 delivers its usual ratio of performance versus price.

Wheels and tyres

Rate the wheels for performance:
 
8/10
Rate the wheels for durability:
 
8/10
Rate the wheels for weight:
 
8/10
Rate the wheels for comfort:
 
7/10
Rate the wheels for value:
 
7/10

Tell us some more about the wheels.Did they work well in the conditions you encountered? Would you change the wheels? If so, what for?

The Quattro LG wheels are solid while offering a decent aero boost thanks to their depth. Swapping them out for some truly lightweight wheels will give the Merlin a massive boost.

Rate the tyres for performance:
 
7/10
Rate the tyres for durability:
 
8/10
Rate the tyres for weight:
 
7/10
Rate the tyres for comfort:
 
7/10
Rate the tyres for value:
 
8/10

Tell us some more about the tyres. Did they work well in the conditions you encountered? Would you change the tyres? If so, what for?

Continental's Ultra Sport tyres are decent performers, but if you really like to push a bike's handling limits then an upgrade would be welcome.

Controls

Rate the controls for performance:
 
8/10
Rate the controls for durability:
 
8/10
Rate the controls for weight:
 
7/10
Rate the controls for comfort:
 
7/10
Rate the controls for value:
 
7/10

Tell us some more about the controls. Any particularly good or bad components? How would the controls work for larger or smaller riders?

The 4ZA components are Ridley's in-house brand and they are decent quality components without being anything flash. They are spot on for the price.

Your summary

Did you enjoy riding the bike? Yes

Would you consider buying the bike? Yes

Would you recommend the bike to a friend? Yes

Rate the bike overall for performance:
 
9/10
Rate the bike overall for value:
 
8/10

Use this box to explain your score

Merlin has played a blinder here, offering a race-proven frame at such a great price. Yes, two grand is still a lot of money for a bike, but it delivers on every level, especially for those who want to travel a large distance at speed, in comfort.

Overall rating: 9/10

About the tester

Age: 38  Height: 180cm  Weight: 76kg

I usually ride: This month's test bike  My best bike is: Kinesis Aithien

I've been riding for: 10-20 years  I ride: Every day  I would class myself as: Expert

I regularly do the following types of riding: time trialling, commuting, club rides, sportives, fixed/singlespeed

Stu knocked out his first road.cc review back in 2009 and since then he's chucked the best part of seventy test bikes around the West Country, a couple of them quite literally! With three alloy and two steel bikes in his fleet he's definitely a metal man (that'll be the engineering background) but is slowly warming to that modern carbon fibre stuff along with fat tyres & disc brakes.
It's not all nostalgia though, after spending the last few years in product design Stu keeps banging on about how 3D printing is going to be the next big thing and he's a sucker for a beautiful paint job too.

3 comments

Avatar
check12 [148 posts] 6 months ago
1 like

Looks a nice bike, good choice of kit. 

Avatar
macrophotofly [292 posts] 6 months ago
0 likes

Sounds great. Hoping they make it available as frame-only (that option doesn't seem to be on the website).

Avatar
Django [25 posts] 4 months ago
0 likes

Hi Stu, 

I'm looking at two possible options of bike, both of which you have reviewed fairly recently. The Bowman Palace R and the Merlin Nitro SL. 

My question is, which would you rate highest ? 

Cheers 

 

Jason