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The Panaracer GravelKing will take some beating on rough roads in this whopping 38mm size. We've already reviewed both the 26mm and the 32mm versions of these tyres and this pothole-conquering, gravel-busting 38mm version in Nile Blue is just as impressive. It's light for a 38mm at 337g, is very easy to set up tubeless and comes in restrained black as well as blue, green and ivory. What more could you want?
First up, this colour is not subtle. Nile Blue turns out to be Teal or Kingfisher Blue with Toffee Brown side walls that coincidentally match my brown Surly Cross-Check perfectly – but you might not be quite so lucky. In which case, good old fashioned black/black or black/tan are available as well.
Secondly, these tyres need a lot of space. They are listed as 38mm but when fitted to some new wider rimed Halo Evaura wheels, they came up to closer to 40 (39.52mm) so make sure your frame can take them before taking the plunge.
Setting them up tubeless proved about as simple as you could hope for. The front tyre went up on the first attempt with an Airshot can and stayed up without sealant overnight, and although the rear needed sealant to hold (that's the idea anyway) both have stayed up for the duration of the test period using Stan's Race sealant.
I figured I'd use this fast-acting sealant, which is capable of plugging bigger holes than the standard option, as I was expecting rough conditions over the winter, but I needn't have worried – or if they have punctured I've not noticed it. So it's a win-win.
Panaracer lists the maximum pressure at 60psi, which is about the most you'd want in a tyre this large. Running them at 50 or under most of the time gave me a supple, comfortable ride and no discernible reduction in rolling speed. It also meant that they coped well with the terrible state of Wiltshire's roads.
One section out of my village is appalling, with the whole top surface broken into loose stones floating on top of the very rough sublayer. On any other road bike this section is horrific and jars your teeth, and you risk riding a long way out from your usual position to avoid it. I was shocked recently when I attempted it on a 28mm road tyre at 90psi – It was almost unrideable – but with the GravelKings you're able to keep the hammer down and plough through. Few actual gravel roads are quite this terrible, so it's a good test of any tyre.
'Off-road' they perform admirably as long as you are not expecting them to grip in wet, slippery mud. They work well on a wide range of mixed surfaces and only spun out when I bit off more than I could chew uphill on a wet, muddy track that proved too much for both the bike and me.
They might be called GravelKing but I take that to mean 'US GravelKing', referring to the hundreds of thousands of miles of cindered roads that the US is lucky enough to have – not 'UK gravel' where we tend to use the term to encompass anything non-tarmac that can be attempted on a drop bar bike. I suspect for most users, the horrific state of many of our UK roads will be more than enough to lead them to Panaracer's gates, and on such surfaces they excel. Using them along the canal towpath, mixed with gravel tracks and farm lanes, I've found the GravelKings to be an excellent, comfortable multi-surface tyre.
Blasting into work on the road has proved both quick and comfortable with no drag issues, which you would normally expect for such wide tyres. I cannot say whether they were faster or slower than the 32mm version Dave tested, but I can confirm that I clocked some of my faster times in and out of work so they certainly didn't hold me back.
Downhill, their 38mm width, Zero Slip Grip (ZSG) natural compound and lower pressures provide an instant confidence boost, holding their line perfectly to the bottom of off-camber, nasty loose surface descents around Bath.
Uphill they performed brilliantly on most surfaces, gripping well up my favourite steep climbs, be they rutted or just plain broken tarmac. Only on the slippery tarmac caused by farm vehicle slime did they require an adjustment of my position to stop them spinning, but I suspect nothing else would have made much difference short of a full-on mountain bike tyre.
As for their puncture resistance, I can only say I'm still running on the first lot of sealant – about 40-50ml per tyre – and I've had no leaks, burps or slashes to deal with, so the Advanced Extra Alpha Cord and the Anti-Flat Casing would seem to be doing their jobs of resisting all intruders.
The Panaracer GravelKing faces some tough competition in the market, particularly from the much-loved and well-reviewed Schwalbe G-One. However, at rrp those will set you back over £60, and they're heavier too. I never felt grip was lacking with the GravelKing – even in the wet I was really impressed with the way they just kept holding on – and their rrp of £39.99 makes them very good value against the G-Ones. Not quite a bargain, but close.
A supremely comfortable, fast, tubeless-compatible tyre for the worst of UK's roads
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road.cc test report
Make and model: Panaracer GravelKing Slick Tread 38
Size tested: 38mm
Tell us what the product is for and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?
Panaracer says, "For cyclists [who] are looking to expand their cycling horizons. That includes roads that may not be suited for normal road tires. Our GravelKing tire solves that problem. Four widths to suit any rider's tastes. Natural rubber compound, puncture protection breaker and a special low rolling resistance casing make the GravelKing a go-anywhere tire."
Tell us some more about the technical aspects of the product?
ZSG Natural Compound : This compound has the same low rolling resistance as the premium compound. Its enhanced wear resistance makes it perfect for a long lasting training tire with an excellent ride.
AX-Alpha Cord: AX technology uses extremely narrow cord which is weaved at a super high density into the casing for lightness and flexibility. This increased density improves resistance to cuts and abrasions.
Anti-Flat Casing: Anti-puncture reinforcement throughout the tire strengthens resistance to cuts and pinch flats.
Really easy to set up tubeless and ran perfectly straight when inflated.
Comfortable and fast (for 38mm) tyre.
No discernible wear, no punctures and no cuts so far.
Ours came in at 337g. The Compass Bon Jon Pass 35 Extralight is lighter but narrower at under 300g, Compass's Barlow Pass is the right width at 38mm but heavier at 450g and perhaps the closest competitor, the Schwalbe G-One Speed 40mm, is 408g so the GravelKing 38mm at 337g is really very good.
Hard to imagine a more comfortable tyre actually fitting your gravel bike.
Tell us how the product performed overall when used for its designed purpose
As a go-anywhere tyre, the GK performs exceptionally well as long as you don't take that 'go-anywhere' literally. Slippery mud is unlikely to be your friend but wet off-camber rough surface roads are fine. Looking at the file tread of the tyre you will be surprised just how good the grip is on all nasty road conditions. It copes well in dry off-road conditions but not muddy fields.
Tell us what you particularly liked about the product
The sheer comfort that the tyre provides, along with the ease of spinning them up to speed and keeping there.
Tell us what you particularly disliked about the product
That Nile Blue really is bright and clashed with just about everything. Thankfully, if you are buying them you can pick your own colour.
How does the price compare to that of similar products in the market, including ones recently tested on road.cc?
The price is good compared to Schwalbe and Compass.
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
A really good tyre that provides sublime comfort and is perfect for multi-surface riding in most conditions.
About the tester
I usually ride: Fairlight 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: commuting, sportives, general fitness riding, mountain biking, bikepacking, adventure, gravel riding