Pete headed to the Borders to meet Gary from Auckland Cycle Works, a man with a very interesting theory on suspension design and a very special bicycle, the Reiver.
What happens when you design a bike around a completely different method of calculating instant centre and anti-squat? The Auckland Cycleworks Reiver is what. Pete headed to the Golfie to ride this one-of-one bike.
Photos by Pete Scullion.
The original Auckland Cycle Works made bikes in Bishop Auckland just before the turn of the 20th Century and would supply the British Army with bicycles in the Low Countries against the Central Powers. Fast forward just over a century and the name sees a reprisal in the form of a bike shop, Inspiral Cycles, just a stone’s throw from the original factory.
With a decade of bike shop experience pervaded by a strong feeling that bike manufacturers had been using a flawed method to calculate anti-squat, Gary Ewing set out to put his theory into practice with the help of Lego, prior to building a bike.
The Marra was the first bike out of the door but the concept came later .Auckland Cycle Works was created as a way to start this experiment. A reverse URT bike was the first step but it all came from this thinking. That being that the instant centre being some distance from ‘traditional’ calculations, and the best way to start building a bike around these new findings was with a reverse URT (Unified Rear Triangle) design. This would allow Gary to find out what did, and what didn’t work, to start on refining the principle. The versatility of the platform wasn’t something tangible until after the fact, however.
With the Marra at the longer end of the range, the Reiver here is at the opposite. Alloy lugs and carbon fibre tubes are bonded together with a double overlap. A key point here is ‘Chassis Stability’, where the bike remains consistent under braking mostly in terms of suspension performance. Gary tells me that ‘normal’ bikes can lose up to 35% of their suspension performance under braking, the Reiver? 5%. The braking anti-rise force in the suspension only performs whilst the rear tyre has grip. As soon as this breaks, the wheel is forced downwards towards the ground in order to find the grip again.
This in turn not only aims to give excellent traction but also smooths out the trail even when under some heavy braking. The rear end also lengthens to offset the compression of the fork too, giving the bike a very stable and composed chassis. The Reiver also exhibits a lot of pedal kickback, whilst simultaneously not… This means that when climbing, the bike should ride almost like a hardtail when in the saddle.
Out of the saddle in easy gears leads to some amount of wallow, but no bike is perfect. When climbing steep and or technical climbs, the platform is designed to shove the wheel over square edges, and offer up a fair amount of grip too. The axle at sag on the Reiver is designed to exhibit a very diagonal/rearward path meaning that more of the anti-squat comes from the axle path than the chain tension, meaning there’s a smaller amount of chain force acting on the suspension.
Sounds too good to be true, right? Well, the proof is in the pudding, naturally. Gary had the Reiver build with a Rockshox Zeb Ultimate with 140mm travel, a 195 x 50mm shock.Cane Creek Kitsuma Coil shock, SRAM XX AXS T-type 12-speed drive, Crankbrothers Synthesis Carbon XC front and Hope Pro5/Fortus30 rear alloy wheels with Schwalbe Albert Radials, OneUp V2 dropper, Hope bar and stem, rounded off with an SQ Lab saddle.
Once I had gotten used to the oval chain ring, the Reiver glided up the fire road and this was especially noticeable on lap two. As Gary said, out of the saddle in low gears it was a bit of a sponge, but there will always be a trade off somewhere. Thankfully, the system is efficient enough that being out of the saddle is a matter of choice rather than necessity. Gary’s started working on a mechanism that will take out the wallow but keep the suspension active…
After a smooth winch to the top of the Golfie, we opted to rattle down Big Baw as it’s got a bit of everything. Almost immediately two things were apparent. Firstly, that the back end was deathly quiet and secondly, the fork was not singing that same tune. Bleeder valves bled and several clicks less low speed compression and the grip jumped and the confidence rose.
So, what about chassis stability? A large part of the bike’s confidence-inspiring ride, beyond the suspension’s ability to smooth out the bumps, was that the bike felt the same size regardless of the speed I rode and severity of the feature ridden.
In order to test the braking grip and suspension performance I did, once up to speed, try a handful of rear brake. All four fingers. It was incredibly difficult to lock the back wheel. All you would get was rapid, controlled deceleration and grip. No oddities, no kicking, no nothing. Just control.
It is hard to articulate how easy it is to rip on the Reiver. I was pushing on from the first turn and the rear end just dealt with all manner of stuff in the same composed way. Even the Borders-specific delight of an overhanging root step in the middle of a corner didn’t seem to bother the bike any. You could be lazy and simply plough through the rocks on the open bit of Big Baw and not hang up. Choosing a line or hopping over the rougher bits just meant even more speed.
For a bike that offered so much quiet composure, after a few runs, the bike felt wonderfully playful if I didn’t fancy just straight ploughing through things. Ploughing isn’t my style anyway, and can’t be at all 60kg of me. Avoiding the rough stuff is my M.O. and this involves a lot of what I call ‘hoppity skippity’, using trail features for that small bit of air that will keep the wheels out of the chunder where possible. The Reiver made this feel very straightforward and the wealth of grip available meant that I could hazard a risky line for a landing rather than needing to take the safer option.
There was a quiet confidence about the Reiver that passed onto me when riding it. Inners was slick and it didn’t seem to matter all that much. It’s testament to the suspension system that after a day of ripping laps, I didn’t once feel the need to make any shock changes. The high leverage ratio meant that I was running a spring a few hundred pounds heavier than I would normally.
“How much travel do you think it’s got?” Gary asked me after the ride. He was keen not to talk numbers before the ride. Over a blackcurrant and lemonade, I made my informed guess. The 140mm fork certainly gave me an idea, I have ridden bikes with 40mm more suspension that felt less capable and didn’t pedal back up the hill as well as this does. “125mm”, I offered. “You’re 3mm out” was his reply. At no point did I feel like I was riding a bike with this little travel.
