Lightweight speed machine with excellent off-road handling while being no slouch on the road either
Jan 18 2018
MTB inspired geometry works off and on road
Drivetrain gappy for road use
Tyre compound compromised in wet conditions
You are looking for a true all rounder
Merida’s mountain bike inspired gravel bike, the Silex 9000, got our tester grinning over a variety of terrain, offering excellent off-road handling whilst still able to turn a wheel easily to road riding too.
I'm guessing if you're considering buying a gravel/adventure bike it's because you fancy some off-road treks into the wilderness or a quick blast around the local trails but is the mainstream way of thinking being that you need a road bike with large clearances the right one? Merida's new Silex 9000 obviously doesn't think so and you know what, I totally agree with it. This is the best bike of this genre I've ridden away from the tarmac.
Road bikes don't really work off-road full stop but many a rigid mountain bikes have found themselves tweaked into commuting service without issue so Merida's school of thought introducing mountain bike geometry to their new gravel bike makes a lot of sense. Most people who are going to be buying this kind of bike are likely to spend the majority of their riding time away from the tarmac lanes, I certainly know I do every time I get one into test so why not have it's best handling attributes suited to that terrain.
The Silex 9000 gets a full carbon fibre frame and fork and it's a very good one indeed. Some carbon frames can feel a little dull through a combination of fibres used and how they are laid up but you get none of that here. You feel everything that is going on from a ride data point of you while the frame takes out the repetitive stuff you don't need like road buzz and minimal vibrations.
Up front the fork has a tapered steerer for added resistance to steering and braking forces plus the legs stand up to the job too. Under heavy braking, there was no judder whatsoever. The front wheel is held in place by a 12mm through axle which is the standard that seems to have been adopted for road applications. You also get internal routing for the brake hose plus there are various mounting point for racks, guards etc. The frame uses a through axle for the rear too, plus it matches the fork in having flat mounts for the brake calliper.
Both frame and fork have clearance for up to 42mm tyres in 700c guise but you can also run 650b wheels with a maximum 2.25” tyre width if that's your thing, which certainly adds to the versatility of the bike. Adventures are in the Silex's DNA so the frame is adorned with more attachment points than normal. You get three bottle mounting positions, one on the seattube, one on the top of the down tube which also happens to offer some adjustment to allow for top tube bag clearance plus another underneath the downtube. There is full provision for guards as well. You won't need to worry about cables getting in the way either as the Silex 9000 has internal routing and the entry ports clamp the cables and hoses under pressure to stop rattling. A simple idea but an appreciative one.
As you'd expect for a bike costing £3,500, this range-topping 9000 model is well specced. You get a Sram Force 1X groupset with a large spread of gears that I found could get me up virtually every hill I tried in the saddle. It uses a 44t chainring paired with an 11 speed, 10-42t cassette which worked fine for off-road use if a little gappy between cogs for road use. I ride within quite a narrow cadence band so I find wide-range cassettes upset my rhythm. Thanks to that small 10 tooth cog at the back, top end speed isn't really hampered as a cadence of 98rpm will achieve 35mph - it's spinny but not uncomfortably so.
The shifting at the Force lever was as sharp as ever and the rear mech sees the chain skip up and down the sprockets without issue even under load. The clutch operated mech also keeps chain tension high and I never had an issue with it coming of the chainring no matter how rough the terrain.
For slowing down Merida has specced Sram hydraulic disc calipers from their Rival range paired up with 160mm rotors front and rear. The stopping power is impressive even against other disc setups like those from Shimano and they are a real joy to use and there shouldn't be any issues with fade when the bike is fully loaded.
Wheel wise the Silex 9000 wears a set of Fulcrum's Red Passion 3 29er wheels which have a very good claimed weight of just 1,500g. This works in partnership with that lightweight frame and helps achieve the Merida's responsiveness I mentioned in the ride section up top. With 28 spokes (14 each side of the hub) front and rear they are a strong set of wheels and certainly didn't grumble with the amount of abuse they received over the test period. There a lot of big rocks hidden in the local gravel trails and I whacked a fair few off them. As far as finishing kit goes it's all in-house Merida branded stuff. The bar and stem are both aluminium alloy which I was happy about for the type of riding intended for the Silex. The compact drops of the handlebars give plenty of hand positions and thanks to that tall headtube they'll all receive a lot of use. Other than that it's just the Prologo Scratch 2 Tirox saddle to mention which is a comfortable perch for any style of riding you might embark on. It has enough flex in the hull to take the stick out of the rough tracks and trails.
I've ridden a lot of gravel bikes over the last year and they've been very competent, good in fact. The second I turned the Silex 9000 onto the track it just felt absolutely spot on with that little realisation where you know the next part of this ride was worth the 25% climb onto the ridge.
Just looking at the side profile you can see where the Silex has taken its inspiration from. The mountain bike style long, drawn out and heavily sloped top tube in relation to its size is completely alien to the road scene, throw in that short stem (90cm) to keep the reach sensible but the steering quick and it's not really like anything else on the market. The 430mm chainstays are generous as well, they bring stability by extending the total wheelbase out to 1044mm on this S/47cm model plus it gives your heels plenty of clearance should you want to fit a rack and bags for full adventure mode.
Up front, though you do get a very tall headtube of 180mm. This according to Merida is because of the number of riders they see with stacks of headset spacers below their stems but it's still not high enough for them to use the drops effectively, not to mention the increase in flex. The Silex allows you to do this especially thanks to their own brand compact drops. For high-speed descents or fast flowing sections, you can get in the drops and lower your centre of gravity and really let the bike get on with the job.
Thanks to the long top tube I could still get a low, flat back position and felt totally in tune with the bike as the surface moved around beneath the tyres. Slight changes in body position would see the Silex react instantly and whether on the hard pack gravel or flying through the dry trails in the local woods I felt completely in control and no matter how technical things became the Merida's ability never felt challenged.
The steering is responsive but even with that the short stem the relaxed 71° head angle, compared to others in it’s class, means that it never becomes twitchy. It allows a smooth flow through the bends of a twisty gravel track or flicking the Silex between roots and potholes as you bomb down through a forest trail. Without suspension obviously you need to choose your route through the trees a little more carefully, processing all of the incoming terrain detail and adjusting your line consistently and it's here that the Silex 9000 really comes alive. It was like I'd been transported back to my teenage years when I was doing the same on rigid steel MTB's, that same grin on my face as your elbows and knees fire up and down like demented shock absorbers. The Silex carries a lot less heft than those old bikes though, at just 7.98kg in this build means that the Merida is so flickable and bunny hops with absolute ease. This has a big impact on climbing too making the bike easy to keep moving at pace over undulating terrain plus acceleration is impressive as well.
Merida have specced Maxxis Gravel 35mm tyres on the Silex 9000 and they aren't too bad, a decent compromise for both on and off-road if you are going to be mixing things up a bit on each ride. With no tread pattern to speak of on the central section you need to pick your conditions carefully, if it's wet and even slightly muddy you're going to seriously struggle for traction but as the name suggests they are great on hard pack and all kinds of gravel. The shoulder tread gives you a little bite when cornering hard but that does come as a sacrifice on the road. The Silex is so quick you tend to forget you aren't on a road bike and a fair few times I went barrelling into tight bend on a descent and making it round by the skin of my teeth.
The front end is quite relaxed for a road machine so on the tarmac the steering isn't quite as sharp as it feels off-road. It's only when you're really motoring though that it becomes an issue. As I said though the tyres don't help, they have quite a hard compound which lacks grip and cancels out a lot of the feedback from the road and high speed handling can be a little vague. I'd find myself constantly tweaking the bars correcting my line all the way through the bend. If you are going out for a road ride specifically it'd definitely be worth changing the tyres for some slicks, once that's done I had no issues whatsoever and the Silex is a very competent and confidence inspiring bike no matter what you are doing on it.
Comfort is another place where the Silex 9000 scores highly. That sloped top tube leaves a lot of seatpost exposed which creates plenty of flex sometimes to the point where I'd glance round to check I didn't have a rear puncture. I rode the tyres at road pressures (50psi) on the gravel just to see what I could get away with in terms of comfort and apart from a bit of road buzz through the hands the ride was still very pleasant indeed. I could imagine this bike being an awesome choice for something like the epic 200km Dirty Reiver event. Merida has designed this bike to work with a 30.9mm diameter post so that you can replace the standard item with a dropper post if you so desire.
The final say
The GT Grade has long been my firm favourite in the adventure genre and doesn't look to change anytime soon even if the frame and fork could do with a bit of a revamp due to its post mount brake fitment and quick release rear wheel attachment. For 2018 the Carbon Pro model uses a very similar build to the Silex 9000 but is around £600 cheaper, the Merida does have a lighter frame and handling more suited to the gravel tracks. There are plenty of other models in the Silex range if this one is a little too high on the price front. The Apex equipped carbon fibre Silex 6000 is available for £2,250 or there are the alloy framed models, 600, 200 and 300 which heavier but much cheaper at £1,700, £1,250 and £1,000.
Overall the Silex is the perfect bike if you are going to spend a lot of time off the beaten track thanks to that excellent handling and fast, responsive ride. The fact that it doesn't really sacrifice its tarmac manners makes it a true all-rounder.
Was the bike comfortable to ride? Tell us how you felt about the ride quality.:
Yes, comfort was very high on the agenda especially thanks to how much exposed seatpost there is on offer.
How was the bike in terms of sizing and angles? How did it compare to other bikes of the same stated size and intent?:
The stack and reach figures both read bigger than normal on the Silex due to the long top tube and tall head tube but the short stem and lack of headset spacers means real world measurements are similar to most other gravel bikes.
Riding the bike
Overall rating for frame
Did the bike feel stiff in the right places? Did any part of the bike feel too stiff or too flexible?:
Frame stiffness is very good indeed making it great for those short sharp climbs you find off-road.
Tell us about the build quality and finish of the frame:
The frame is well made and neatly finished with attention to details
Tell us about the geometry of the frame:
The Silex is heavily influenced by MTB geometry rather than being based on a road machine. This makes for a very distinctive looking machine which really excels off-road.
Full details can be found here - https://www.merida-bikes.com/en_gb/bikes/road/gravel/2018/silex-9000-10628.html
Tell us about the materials used in the frame:
Full carbon fibre for both the frame and fork
How did the bike transfer power? Did it feel efficient?:
Impressive, a great combination of stiffness and light weight
How would you describe the steering? Was it lively, neutral or unresponsive?:
Perfectly suited to the type of riding, quick and responsive without being twitchy.
Tell us some more about the handling. How did the bike feel overall? Did it do particular things well or badly?:
Handling on the road isn't as sharp as a normal race bike but off-road it just works, the best handling gravel/adventure bike I've ridden.
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Wheels & tyres
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Tell us some more about the wheels.Did they work well in the conditions you encountered? Would you change the wheels? If so, wha:
The Fulcrum wheels are light enough in the weight department to compliment the frame while still being strong and durable enough to stand up to the knocks.
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Tell us some more about the tyres. Did they work well in the conditions you encountered? Would you change the tyres? If so, what:
The tyres have to provide grip, rolling resistance and durability across all types of terrain which is a big ask, they do a pretty good job of it though.
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Tell us some more about the controls. Any particularly good or bad components?:
Alloy components for the cockpit make perfect sense for a bike of this style and they provide a good fit too. The saddle and seatpost worked well together to create plenty of comfort.
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Which components had the most effect (good or bad) on the bike\'s performance? would you recommend any changes?:
That tall seatpost allows a lot of flex for comfort
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Use this box to explain your score:
The Silex takes a different approach to the gravel/adventure bike geometry and it really pays off. The off-road handling is superb and on road there is little in the way of compromise. A spare set of wheels and slick tyres would be the only addition I'd recommend for those days when you just want to stick to the tarmac.
Great review, and I'm glad you like it since I've ordered one of the Alu versions.
However you still give the impression, despite the glowing review of the Silex, that the GT Grade is still your favourite 'gravel' bike, but don't really explain why that is compared to the Silex, other than the fact the Grade is cheaper. Can you elaborate?