Two custom bike builders have had a go at making customisable off-the-peg frames – we put an adventure model through its paces

Product Overview

Overall rating:

Score 9

Isen All Season

Pros:

  • Springy frame
  • Comfortable ride
  • Nimble handling
  • Stunning paint job

Cons:

  • Fiddly cable routing – though this can be external
  • We found the paint chipped easily

Product:

Isen All Season adventure road bike frameset

Price as reviewed:

£1,850.00

Isen is the brand created by the joining of two of the UK’s most celebrated frame builders: Caren Hartley of Hartley Cycles and Matt McDonough from Talbot Frameworks. I test the latest offering called the Isen All Season.

The pair share a history in custom frame design, but with the Isen Workshop their goal was to offer off-the-peg frames in a wide size range from 47cm to 59cm.

Every model of the Isen All Season range is built to be completely size specific. This means those on either end of the height ‘norms’ can rid themselves of the compromises in handling that can be found elsewhere.

The range currently consists of the All Season and the Race Ready Road – the former being the model we had on test.

>>> Best gravel and adventure road bikes

It’s a bike designed for anything from bike packing to audaxes and commuting, and I put it to the test over a three day ‘adventure ride’ which traversed flinted terrain, fireroads, a few technical root-strewn trails and sections on the road along the North Downs Way in Surrey and Kent.

Constructed from a mixture of TIG-welded Reynolds, Columbus and Dedacciai steel tubing, the All Season’s steel chassis cuts a slight shadow against the wide-tubed carbon aero bikes we’ve become used to seeing sail through the office.

>>> Does the UK really have the terrain for gravel bikes? 

The bi-axially ovalised down tube isn’t particularly slight for steel, though, and the aim was to create a frame that could power up steep climbs while remaining comfortable over long distances.

Isen All Season

Battle scars can be shown off quite easily on this frame

A skinny 27.2mm seatpost is a second nod to comfort, as is the use of a full carbon Columbus Futura fork. This comes with a tapered carbon steerer and 12mm thru-axles, which use a torx key for removal, and flat mount discs. The rear wheel uses a quick release skewer.

The 51cm frame I had on test was built around 650b wheels, though running wide 1.8in Naches Pass tyres I rode on the almost prehistoric 26in standard, allowing for nimble handling off-road and plenty of tyre cushion.

>>> Should you consider swapping to 650b wheels?

All frames from 47cm to 51cm carry smaller wheels to allow for the ideal proportions elsewhere without any worry over toe overlap. The head angle in this case is 71.5º, with 74.5º at the rear – providing the relaxed ride you’d expect from an endurance and off-road focused machine.

Jumping aboard the Isen, the first terrain that I tested it on was tarmac, en route to the trails.

On the 20 per cent climb from my home town to the ride start it was light enough, even with camping equipment attached. The steel build dropped in at just 9.38 kilograms – an impressive weight for a material that’s got a bad reputation for being heavy.

The springy steel frame felt notably flexible and comfortable, but without being noodly – instead simply providing a pleasant level of feedback from the road. This would be a beautiful blend for long days in the saddle or commutes, though obviously you’d not find enough stiffness in there for harder efforts.

Isen All Season

Image: Adrian Wills

At 5ft 4in I’m on the border for really requiring a 650b wheel, or 26in with wide tyres. On the road, the set-up felt a bit too cramped for me – especially when getting out the saddle as the reach seemed to disappear beneath me.

The 51cm comes with a reach of 359mm, so I’d simply look to size up to a 53cm with a reach of 373mm, which is much more in my ballpark. Of course, a customer would be speccing a bike to their exact requirement.

The stack, 554mm in a size 53, provides a higher front end than you’d see on most road bikes, to suit the all-day and off-road needs of the rider it’s designed to carry.

Once we got off the road, the shorter reach felt nippy and easy to handle and the bike really came into its own on the flinted roads of the Pilgrims Way. A lot of this prowess will come from the rubber fitted to the wheels, but the frame can be credited with soaking up the bumps too.

The wide 1.8in tyres were a massive highlight. On dry terrain, run at 15-20psi (suited to my weight, 58kg), they carried me over a multitude of off-road surfaces without trouble and felt fast enough on the road without humming as a mountain bike tyre would.

Notably, it took just 10 minutes of a heavier rider (75kg) smashing over rocky terrain for them to puncture, demonstrating the importance of getting the pressure right on such a delicate set-up.

My off-roading is restricted to a few weeks a year: when road race season is over and the sweatfest of winter rollers sessions and track racing hasn’t begun. Therefore, I can testify that the bike is able to take even the most unskilled of riders down some techy descents.

On one rocky downhill I had at least three near-miss situations but managed to keep it upright over every one – more than just a bit in part thanks to the stability on offer from the bike below me.

I did briefly swap bikes with a mountain bike journalist riding a full-suspension machine. My ride immediately become very easy, while the the swap ended quickly as she commented “you can have your terrifying bike back!”

Admittedly, the bike was far too small for her and the bars too narrow, but it’s still true that any off-road terrain will be easier and quicker to cover on a mountain bike. But a gravel bike will offer more challenges and some easy thrills, so you don’t have to load your machine into the back of a car and visit a trail centre to get your kicks.

The only sections where the bike’s rigidity became an issue were the grassy fields.

Uphill sections were fine, but flat expanses where the green surface was dented with those easy to miss holes (a bit like the braking bumps on trails, but probably caused by moles and not overzealous stoppers), made for bumpy riding.

Isen All Season

Shimano Ultegra Di2 was a nice touch, although mechanical will do the job

Any Isen All Season purchased will be built up to the rider’s specification, so to a certain extent it’s not worth dwelling for too long on the spec of this model.

However, since spec choices influence the ride (and weight), our model was pretty top end: Shimano Ultegra Di2 shifting and the aforementioned 1.8in Naches Pass tyres fitted to handbuilt Stan Crest MK3 26in alloy rims with an SP dynamo front hub and Hope RS4 rear.

This was finished off with Zipp Service Course stem and carbon seatpost plus Cinelli Dinamo alloy bars (in 38cm) and a Chris King headset, plus my own saddle (Selle Italia SLR Lady Flow).

As a newcomer to ‘adventure riding’, or what is basically a resurgence of touring, Di2 seemed like an odd choice to me since replacement parts can be expensive and not all campsites will come with USB ports for charging. The bolt-thru axle required a torx key to remove the wheel, which meant carrying extra tools.

Routing for brake and dynamo cables is internal, whilst shifting cables can be run externally if they’re mechanical or internally for Di2.

The internal routing of the Isen All Season keeps the cables free from weather damage, but I found the rear brake cable quite susceptible to being ‘kinked’ (for example, when placing the bike in the boot of a car), and replacing cables would be fiddly with this set up. It’s not a job for an amateur fettler and Cycling Weekly’s mechanic wasn’t a huge fan in terms of simplicity of maintenance.

These are largely spec choices, however, and in this case might lend themselves to an adventure racer looking to set fast times over varied terrain.

The 38cm bars were perfect, and it’s notable that receiving correctly sized handlebars from the outset is something most females won’t get when buying a stock bike.

Across all frames of the Isen All Season range, mudguard and rack mounts are provided along with an easily replaceable mech hanger (accidents happen!) and a choice of bottom brackets.

The Isen All Season frame is built to take disc brakes, and can accept electronic or mechanical shifting and 2 or 1x groupsets with no modification.

On an aesthetic note, eagle eyes will notice the Isen asymmetric seatstay bridge and solid brass head tube badge – a nod to Hartley’s past training as a jeweller and silversmith.

Isen All Season

Nice style and details on the Isen All Season

There’s five ‘sik candy fadez’ colour schemes, all produced in house at the London studio. The paint job is definitely awesome. However, when a fellow rider leant a metal studded pedal against the frame (quelle horreur!), I did notice that the paintwork is easy to chip – though arguably you’d need lacquer as hard as nails to withstand a metal pedal.

Value

At £1,850 the Isen All Season is far from cheap, but for a stunning handcrafted frameset it’s not excessive either, and you could easily spend the same on a more mass-produced specimen that won’t come with the same level of individualisation.

This model would come in at £5,126, plus saddle and pedals – but it’s a top end build.

Verdict

A springy steel frame that manages to be comfortable without being overly flexy, with a size-specific geometry that feels nippy and caters well for obstacles off-road. The paint job is beautiful – but perhaps a little fragile.