J.Laverack R J.ACK Disc

The J.Laverack R J.ACK was one of the standout bikes last year. We were so impressed, in fact, that it made it to the road.cc Superbikes of the Year against a field made up entirely of carbon fibre rivals. For 2018 the young British company has introduced a disc-equipped version of the R J.ACK and managed to retain the velvety smoothness and composed handling with all the benefits of disc brakes and increased tyre clearance, though there is a weight penalty.

• Pros: Smooth, comfortable, fast, nice handling, looks good
• Cons: Weighty, pricey

Titanium is a wonderful, if expensive, material from which to build a bicycle frame. With the J.Laverack R J.ACK it provides a nice balance between stiffness and compliance: it has the necessary stiffness to ensure direct handling and responsiveness for energetic and pacy riding, yet is composed and compliant over the rough roads that are a regular feature around most of the UK.

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Adding a disc brake option was a no-brainer. Disc brakes are increasing in popularity, becoming more widespread even on bikes designed for racing or high-performance riding, as the J.Laverack R J.ACK is. There are pros and cons to disc brakes, and they're not for everyone, but all I will say is if you do try Shimano's latest hydraulics, you might find it very hard to go back to rim brakes with carbon wheels. With the J.Laverack R J.ACK, you now have the choice of rim or disc.

Ride and handling

Much of what I wrote about the original R J.ACK holds true with this new disc brake version. It's a fast and smooth bike, covering ground swiftly and doing so with the high refinement you'd expect from titanium. The smoothness is its big highlight, and really does wonders to transform my local roads into something a little less harsh and jittery.

It's no marshmallowy ride, though. There's evidently enough stiffness in the frameset, bolstered by the carbon fork, to ensure it's a thoroughly entertaining ride when you want to go fast. The geometry gives the R J.ACK a touch slower steering than some race bikes, which sees it being very docile at high speeds. It never once got skittish even down some of my steepest and rattliest descents, and the Shimano hydraulic brakes make it easy to control your speed. If you want extra confidence, this bike offers it.

If there's a downside to the new bike, it's the weight increase over the rim brake version. This bike is, more or less, a very similar build to the one I tested last year, but it's giving away about 600g. That does sound like a lot on paper, but to put it in perspective, it's about the same as a full 500ml water bottle. So ask yourself, do you feel faster when your water bottle is empty or full?

Frame details

Ignore the disc brakes, and visually the new frame is identical to the rim brake model.

There's the same 3Al-2.5V double butted titanium tubing with a squashed top tube, tapered head tube and threaded bottom bracket. The stays are a lot curvier, though, necessary to ensure the flat mount brake calliper is in the correct place and provide adequate heel clearance.

Even the 'race' geometry of this test bike is essentially the same, though you could choose the 'classic' option which uses J.Laverack's new carbon fork and has slightly more relaxed geometry if you want race bike performance without the back pains.

As usual, the attention to detail and quality of the finish is first class – very much what we're used to seeing from this young company. J.Laverack is big on customisation, with a choice of finishes and other options to choose from, so although not a bespoke bike as such, you can tailor it to an extent.

As already mentioned, some of the details on this bike are carried over from the previous version. That includes internal cable routing, which on this bike has been optimised for the electronic groupset, and the external threaded bottom bracket, but you could choose a press-fit if you prefer (ha!).

Where it is different is in the fitment of the Enve Road Disc 2.0 carbon fork and the new stays and dropouts. J.Laverack has developed new cowled thru-axle dropouts with a flat mount on the non-drive side. It's very nicely done, all clean and tidy. Lever-less thru-axles require an Allen key to operate but do leave nice clean axle ends, which I like.

Switching to disc brakes has boosted the tyre clearance on this bike. There's space for up to 32mm tyres, up from the 28mm limit imposed on the previous bike by its rim brakes. With a growing interest in wider tyres, it's great to see this increased choice, and speccing 28mm tyres on this model is a smart choice for helping to smooth poorly surfaced roads.

An interesting deviation from the original rim brake version is the development of the two geometry types, mentioned above. We have the 'race' version with the most aggressive geometry and a stock Enve fork, as tested here, and the 'classic', with slacker, more relaxed geometry and the company's own fork. The classic actually sits a bit closer to the company's original J.ACK road bike.

"We wanted to translate the proven geometry, speed and agility of the original R J.ACK to a disc brake model in order to a create a spirited and elegant bike for the discerning road rider," explains Oliver Laverack, designer and founder of the company.

Each frame comes with a 10-year warranty with the original owner.

Build

J.Laverack will happily sell you a frameset for £2,380 or a complete bike customised to your needs, with full bikes starting at £3,650. If you're feeling flush and want to blow your bonus/pension/inheritance/student loan on an £8.5k superbike build, this Shimano Dura-Ace Di2 bedecked beauty could be yours.

Dura-Ace Di2 is the current benchmark groupset, slick of shifting and strong of braking, with arresting looks and flawless durability. The hydraulic brakes with the new Freeza rotors offer highly impressive braking, powerful and easy to feather in any situation, whether tackling a tricky descent or weaving along the road in a fast-moving peloton.

J.Laverack has decided to commit to producing its own carbon fibre wheels, and my impressions of the Aera AR|36 wheels are very positive. The wide profile works well with the 28mm Schwalbe Pro One tyres, providing a broad platform, and the aero performance, in so far as I can determine using speed, power and seat of the pants feedback, is commendable. They're laced onto Chris King R35 hubs which look and sound glorious.

I'm no fan of the Brooks Cambium saddle, though I know many people are; it's no bother to spec a saddle of your choice or simply change it.

The PRO Vibe carbon seatpost and handlebar with aluminium stem all look like good kit on a top-end build like this and functioned without flaw. I particularly like the shape and reach of the bar.

A set of J.Laverack's own titanium bottle cages completed the build – a good move as I don't think carbon cages would quite look right on this frame. What do you think?

Rivals

I can count the number of disc brake-equipped titanium road bikes road.cc has tested on a single hand. Not many, but there have been some standout bikes.

> Buyer's Guide: 14 of the loveliest titanium road bikes we've ridden

Most recently there was the Van Nicholas Skeiron that offers high performance for the non-racer but is a fair bit heavier. If you want more of an endurace focus there's the Enigma Evoke Disc which also takes 32mm tyres and offers a delightful ride.

If you're not bothered about disc brakes, there is, of course, the rim brake R J.ACK or you could consider the Reilly T640.

And, just to show how light you can get a bike for the same money, there's the Specialized S-Works Tarmac SL6 weighing in at 6.3kg!

Conclusion

Apart from the stellar price, it's hard not to like titanium as a material choice for a bicycle, and when it's created with this care and attention there's really a lot to like. Okay, so J.Laverack doesn't craft the frame itself, few builders in the UK do these days, but it has produced a smart and distinctive looking frame with solid handling and nice attention to detail.

Verdict

Sporty performance, silky smoothness and all the benefits of disc brakes