What is it?
A fast rolling gravel tire that leans toward the dry, sandy conditions – puncture protected, available in two sizes, and Sven Nys approved.
- Puncture protection is top-notch under demanding conditions.
- Fast-rolling tread on various types of limestone and gravel.
- Predictable cornering knobs offer confidence on dry grass and dirt
- Tan sidewall boosts the look of any bike (personal choice)
- Not a great performer in wet and muddy conditions.
- Lightweight but weighs more than claimed.
- Could roll faster on the road 60a/52a compound
Gravel riding is blowing up, the idea of components and gear specifically designed to ride this style is coming faster than we all can process. Do we need all the gravel specific, bags, bars, beers? Well – I would be down with a gravel beer, but the main limiting factor for most riders on gravel is comfort and confidence. Comfort knowing they can ride for seemingly endless miles to nowhere and feel secure. Confidence knowing they can take a corner fast or know they have the right gear and won’t need to call for help – or even worse an ambulance. For me, the most crucial piece of bike gear for riding drop bar off the road is the tires. It may be the cyclocross racer in me, but I feel that riders have much to gain from choosing the right rubber and even more to lose with the wrong.
Gravel rides and races are notoriously hard on equipment – especially tires. Nothing is worse than getting into the groove in a long race and feeling that squish of a tire running flat. Sven Nys felt that many times in 2018 during his attempt at the Dirty Kanza 200. The cyclocross champions ride was riddled with a flat tire after flat until he opted for a wheel/tire change. What tires did he change to you ask? The Bontrager Team Issue GR1, Sven rode the remainder of the race flat free, and I imagine a bit happier.
The Bontrager GR-1 tires are simple and effective – no over-complicated tread design – no super high thread count. The tread is similar to what you’d expect from gravel driven tire, tightly spaced knobs, dual compound, fade to high cornering knobs. The pattern is a slight chevron shape with spacing gradually fading as the tire curves. The GR-1 has a 60a/52a compound that makes it roll fast on the hard packed and grip on larger pieces of gravel. Sidewall protection comes in the form of Bontrager Innerstrength casing which employs the use of nylon around the side walls only to reinforce the cut zone. The GR-1 are available in two sizes 35mm/40mm and black or tan sidewall colors.
Tubeless is a must have for gravel – the ride is smooth, and the flat protection is paramount. The GR-1s setup quickly with the use of a floor pump and Bontrager Sealant. The bead slides easily into place with little to know rim wrestling. The tread application is poker straight, and the knobs are tacky and sturdy.
On the road, the GR-1 feel like a gravel tire, not too fast but surprisingly springy on acceleration. When you enter the gravel sectors though, the GR-1 comes alive. At 50psi the GR-1s roll like they are at a much lower pressure, the ride is comfortable and supple. The center line tread gives a similar ride feel to file tread cyclocross tires but with added grip with no rolling resistance penalty. The tread is grippy, so much so that I can hear the gravel being thrown into my fenders sometimes on the climbs. Anyone whos a gravel rider knows that feeling of grinding up a steep climb and – boom – you spin out and struggle to get your footing. The grip on the GR-1 never left me searching for grip on the climbs, even when the road was damp. The cornering is predictable, the round profile of the GR-1 makes it easy to stomach rolling into a berm at high speed, knowing the grip is there. On larger chunks of gravel the tire holds its own, the Innerstrength side wall lived up to the hype and never cut or punctured. I even took the GR-1 on the local singletrack and was pleasantly surprised at the grip and speed on the dry trails. The sidewalls and the overall ride is comfortable, and the feeling is more like a high-end cross country tire. I like the fact they come is 35mm/40mm offerings, giving the rider the ability or mix tires depending on course conditions and volume needed – all the while having the tread and performance to what they are accustom – Plus the 35mm fits most cyclocross frames and makes a great training tire that is capable in the woods.
The only time I searched for grip was in the wet and sloppy conditions. These cross conditions do arrive at gravel races, though few, they could be a race changer for some. The GR-1 does perform better in the mud when running around 28-30 psi but is still a dry weather tire.
All said and done the Bontrager GR-1 Team Issue tires blew away my expectations. I went from gingerly rolling through the rocks to sending it off of slabs – totally confident in the tire. For those looking for a gravel tire that can roll fast and not flat – look no further than the Bontrager GR-1.
Sizes: 35mmX700-(tested) 40mmX700
For more information grind over to Trekbikes.com