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The Rene Herse Barlow Pass tyre is a tubeless-compatible (TC), ultra-supple tyre that delivers an astonishingly smooth and grippy ride. If your bike can't fit them, maybe you need a new bike. They're that good.
Rene Herse (formerly Compass Cycles) grew out of the magazine Bicycle Quarterly, founded in 2002 by Jan Heine, a Seattle-based long-distance cyclist and journalist. I've referred to their seminal work on optimal tyre pressure for years, the chart by Frank Berto showing the best guide pressure for tyre size permanently taped to my workshop wall. Once was the time I ran 23mm tyres, just like everyone else, pumped up to 100psi, with the commensurate need to have either a full CO2 canister or a top-spec mini-pump and arms like a gorilla always in your mind.
Fast forward to 2010 and 28mm tyres were becoming commonplace, pressures dropping as the volume increased, affording more comfort and more grip alongside improved puncture resistance. The 28mm bandwagon rolled on as firms such as Continental with its excellent GP 4Seasons and GP 4000S II made their tyres readily available in the 28mm size. Then Schwalbe pushed past 30mm with the frankly stunning S-One 30mm tubeless tyre and it was game on as everyone went fatter.
Taking the Barlow Pass tyres out on a 40-mile loop mixing gravel with tarmac in equal proportions, it is obvious the benefits that large, supple tyres at low pressures bring. At the end of the loop, after months of trying, I smashed a 1km Strava sprint segment, knocking five seconds off my previous best and setting a KOM benchmark for summer that the previous holder is going to be hurting to regain. This is my personal validation of the German Tour magazine results discussed below, that fat tyres are every bit as fast as skinny. The fact that you remain supremely comfortable and have prodigious amounts of grip on hand for cornering and braking adds to the rationale for going wide.
Going properly off-road into rooted and rocky singletrack, the Barlow Pass was only defeated by 15%-or-more slopes mixed with slick clay or rocks. Otherwise, the super-supple casing deformed around and gripped to trail irregularities with amazing ease.
Wider is better, there is simply no argument. Outside of a velodrome, in the real world, there is now a ton of data both empirical and anecdotal on rolling resistance, puncture resistance, aerodynamics, hysteresis loss due to vibration, grip and pretty much every other tyre-related metric you can think of, that proves going wider on the right rim will make you faster and more comfortable.
Fundamentally, a fatter tyre is free suspension. Every vibration you don't feel is energy saved – anything that bumps you and your bike up and down is sapping energy that could be propelling you forward; anyone who's ever ridden a bike along a farm track where a tractor has left its tyre marks knows this all too well. But that's only part of the picture.
You could argue that if you live in the Swiss Alps or parts of Belgium, the roads are so smooth you don't need anything to save you from vibration. But you still have the matter of tyre footprint, and the sidewalls flexing every time the tyre rolls forward. This is the 'rolling resistance' that German cycling magazine Tour is famous for testing, and in early 2018 they confirmed that the Rene Herse Bon Jon Pass, a 35mm version of the Barlow Pass, is one of the five fastest tyres in the world.
This is stunning news because at 35mm wide, the Bon Jon Pass is far larger than the rest on test, at 23-26mm. Tour's test protocol also ignores the main reason for riding a wider tyre – comfort – because they test on a rolling road with no rider aboard the wheel. Another factor is that the other tyres on test are significantly thinner: the winning Vittoria's tread was just 0.8mm thick compared with the 3mm on the Bon Jon Pass.
Rene Herse makes model selection easy, as there are only three variables: width, casing weight and tubeless compatibility. The 26, 28 and 32mm models require inner tubes, while the wider versions can run tubeless with a latex-based sealant. Latex-based matters, because there's no butyl liner to keep non-latex sealant inside. All tyres use the same handmade vulcanised construction method and fine herringbone tread, apart from the 38mm Steilacoom which has a cyclo-cross/mud-friendly knobbly tread.
All models come with an 'Extralight' casing option for £15 more – on the Barlow Pass you get a more-supple casing that's 44g lighter per tyre. You'd expect that a lighter, more supple casing would be more prone to punctures, but remember, it's the sidewall that is flexing and that's not in contact with the road. So with the same tread as the standard casing, the Extralight version simply ups the comfort while lowering the weight – you get what you pay for. The Extralight is also available in all-black, if you don't rock the tan sidewall look.
Rene Herse tyres are made exclusively in Japan at the Panaracer factory. Panaracer is famed for its Smoke and Dart mountain bike tyres, still in production after 20 years. Rene Herse worked with Panaracer to develop its line of tyres, and the relationship is close, with staff visiting and getting deeply involved in the design process.
Rene Herse is strident in advising that its tyres should not be run beyond 60psi tubeless, although on the casing it says 75psi, so there's an amount of nous required. At 60psi each tyre can carry 60kg for 15% tyre drop (the amount the tyre depresses), using the Berto chart of recommended pressure, making the Barlow Pass a tyre that a fairly hefty bike-and-rider all-up weight could run tubeless.
There's a good guide that Rene Herse provides on tyre fitting on the rim, with a guideline around the bead that you have to check is evenly seated.
As mentioned above, you need a latex-based sealant because of there being no butyl liner in the sidewalls so as not to impact suppleness. Rene Herse 'strongly' recommends using Orange Seal because of its thicker nature quickly sealing any holes. I didn't have enough Orange Seal to hand, and managed to get a good seal with Caffélatex.
As with anything high-end, it pays to read the literature to get the best performance. Rene Herse is unashamedly designing for the performance-orientated aficionado, not the mass market.
My initial setup was on the trusty Merida Ride 5000, the tyres measuring 37mm on 17mm internal width rims. The frame/fork clearance afforded was paper-thin – to the point that any pressure above about 30psi had the tyres rubbing. On this rim combination I had to let the tyres set up for a day with inner tubes inside. Once they were nicely shaped they inflated tubeless with no hassles, with a reassuringly loud amount of popping bead onto rim.
Extrapolating the go-to Berto chart of tyre width vs. optimal pressure for 15% drop, the target was around 35psi – but going 5psi lower felt no different.
On my first ride out around a fast loop, I noticed bouncing at high cadence halfway through. A quick stop and pressure check indicated my rear tyre was down to a frankly ridiculous 20psi on account of the sealant having yet to find all the tiny sidewall holes and plug them. I hadn't noticed a change in handling or ability to soak up road surface irregularities. Unless I sell this bike on, I'll be getting a set of the 35mm Bon Jon Pass tubeless-compatible tyres as soon as possible.
Fortunately at the same time I had the Marin Cortina AX1 cyclo-cross/gravel bike on review, so was able to fit the Barlow Pass to the 20.5mm internal width rims and inflate to 60psi with no clearance issues. At 35psi the Barlow Pass measured at 40.5mm – affording a massive amount of cushioning and grip on or off-road.
Jan Heine, Rene Herse founder, is arguably the world's foremost expert on tyre pressure in a mixed road-gravel scenario, and has written some excellent advice on how to get the optimal setup. After a decade of following and passing on this advice, I can personally vouch for every word. Wider is better, and if in doubt, let air out.
Yes, there's a weight penalty for that much rubber – nearly 400g heavier than the Continental GP 4000S for a pair, should you be looking for an excuse not to go past 28mm. However, this does not factor in how much more grip/comfort/volume and therefore speed/reduced fatigue/puncture resistance you will benefit from. Let's face it – if 400g is going to make or break your day out riding, you probably have a support car behind you.
The closest logical competition to the Barlow Pass has to be the Schwalbe G-One 700C 38mm, at an RRP of £58.99 (often cheaper). The major difference is that the G-One features a butyl liner in the sidewall, so you can run a non-latex sealant (yay) but there's a compromise in rolling resistance (boo). The G-One is an excellent tyre, no doubt, but the Barlow Pass is in a different league, rolling resistance-wise.
The subject of puncture resistance is probably the most contentious topic in cycling circles, as it's almost impossible to quantify in a replicable manner. Suffice to say the anecdotal evidence of people riding 300km gravel races on Rene Herse tyres without flatting is reason to consider. Add in the new tubeless compatibility, even more so.
Better tyres are the easiest and most-frequently made upgrade to a bike. The Rene Herse Barlow Pass (and narrower siblings) are highly recommended for pretty much any kind of road or gravel riding. The science is in – wider is better.
A supremely grippy, comfortable, fast tubeless tyre with no downsides
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road.cc test report
Make and model: Rene Herse Barlow Pass tyre
Size tested: 700Cx38
Tell us what the product is for
These are for people who value speed and comfort, on and off-road. A connoisseur's tyre.
Rene Herse says:
"The Barlow Pass tires is named after a pass on the Mountain Loop Highway, a scenic gravel road through the central Cascades. The road leads past the ghost town of Monte Cristo before ascending the pass. On the long straights and sweeping turns of this gravel road, the extra stability of a large-wheeled bike can provide an advantage as you descend at high speed.
The Barlow Pass is a great road tire for 700C bikes with moderately large clearances. If you prefer a true dual-purpose knobby in the same the 700C x 38 mm size, check out the Rene Herse Steilacoom.
The Barlow Pass is tubeless-compatible.
When used with tubes, we recommend the SV17 or SV18 tubes."
Tell us some more about the technical aspects of the product?
From Rene Herse:
Clincher, folding bead
Low rolling resistance
Clincher tires with the ride of a good tubular
Maximum pressure with tubes: 75 psi (5.2 bar)
Maximum recommended pressure – tubeless: 60 psi (4 bar)
As "Standard" model, but with:
Ultra-light, ultra-supple casing
Choice of black or tan sidewalls
Further improved comfort and traction
Ultra-low rolling resistance
No nicks or cuts evident after hundreds of fast miles on and off-road.
Its 461g is at the heavier end, but you make it all back in comfort and speed.
Amazing. Just amazing.
They're £4 cheaper at RRP than the nearest equivalent Schwalbe offering. Whether they're worth shelling out for depends on how much you value comfort and speed. If you're happy being bounced around and don't want to go fast, cheaper options are available. Other large-volume tubeless tyres are available, from the likes of Schwalbe in particular, but Rene Herse wins the sidewall compliance shootout, with no Schwalbe tyres appearing in the likes of the Tour tests for rolling resistance.
Tell us how the product performed overall when used for its designed purpose
Amazingly well. They stick like glue and are so comfortable.
Tell us what you particularly liked about the product
The supple ride. Miles seem to evaporate under the Barlow Pass.
Tell us what you particularly disliked about the product
Did you enjoy using the product? Yes
Would you consider buying the product? Yes
Would you recommend the product to a friend? Yes
Use this box to explain your overall score
I can only mark the Barlow Pass down on price – £54 is a lot of cast per end. That said, compared with the logical competition from the Schwalbe G-One Tubeless 700C 38mm at an RRP of £59, it's excellent.
About the tester
I usually ride: Merida Ride 5000 Disc My best bike is:
I've been riding for: Over 20 years I ride: A few times a week I would class myself as: Expert
I regularly do the following types of riding: cyclo-cross, club rides, general fitness riding, mountain biking, Dutch bike pootling