Compass Steilacoom TC tyre

The Compass Steilacoom TC tyre is a fabulously grippy, fast-rolling tyre off-road that displays frankly ridiculous speed on the hard stuff too. The performance comes at a price you'll forget the moment you hit the first transition from tarmac to gravel.

Pros: Stupendous grip over rocks, grass or gravel; roll on tarmac with unbelievable ease

Cons: Price, but on-par with the logical competition and you get way more than you pay for

The Steilacoom TC ('Tubeless Compatible') is the only 700C knobbly tyre from Compass Cycles, maker of artisanal-grade super-supple clinchers and many other items of high-end cycle kit. Compass has a strong relationship with Japan's Panaracer, and has its tyres made by Panaracer in batches to its own secret specifications.

> Buy these online here

The Steilacoom is only available in one 700C size – 38mm – and two casing variants: the as-tested Standard (tan only) and Extralight casing (saving you 50g per tyre with a more supple ride, in tan and also black). There's a 650B variant too – the Pumpkin Ridge TC – which is a plush 42mm wide with the same tread design.

Compass named the Steilacoom after a cyclo-cross course near Seattle, Washington. That's the roots of the tyre's origin: to provide the same ride as a 33mm cyclo-cross tubular, with the much lower cost and reduced hassle of a tubed or tubeless clincher. Compass reckons in order to achieve the feel of a 33mm tubular, 38mm is the way to go – and to hell with the UCI's 33mm limit – who races clinchers at UCI-sanctioned level anyway? If you're a contender, you have a mechanic to glue up your tubulars to cure in a basement ahead of the season.

Another nod to the cyclo-cross pedigree is the knob design, harking back to classic CX tyres with their round knobs. Compass has gone with rounded squares looking down, with sharp edges viewed sideways. The thinking is that the edge can bite into the dirt or grass, while the tread as viewed from above has no sharp edge to hold a cake of mud between knobs, thereby clearing much faster. The tread comprises two knob sizes – in the centre there's a row of alternating small knobs that become larger and wider-spaced at the edge.

Setup

As is often the case with a very supple tyre, tubeless setup wasn't without its nuances on the Miche AXY-WP rims on test at the same time. Failing to seat despite best efforts, I let them sit for a night with an inner tube in place, then removed just the one bead, removed the tube and everything then seated just fine. Possibly they would have seated immediately after fitting an inner tube with the one bead locked in place, but going overnight didn't hold up the process. Then 60ml of Stan's sealant, and after a quick test ride things stayed inflated for a month of rocky, gravelly thrashing. Noting as Compass doesn't use a butyl liner to airproof their sidewalls you'll need to go with Stan's, Orange Seal or another similarly specced sealant.

> How to fit tubeless tyres

For my 73kg weight I ran 30psi at front and 35 at rear both on and off-road; these may sound foolishly low, but it's all in the science, which I won't rehash here. Suffice to say, for a super-supple tyre, go wide and go low.

Performance

On my first long on-off-road foray into the Highlands, the Steilacooms provided amazing, genuinely confidence-inspiring grip. Out-of-the-saddle high-torque climbs up 20%-gradient short, wet grass presented no challenge – absolutely no slipping was felt, even leant as far over the bars as I could go to keep the front wheel planted.

The Tifosi Cavazzo test bike was the 'commuter spec', with a quite high 34x27 low gear requiring an unseemly amount of out-of-the-saddle muscling to clear tricky bits. Even over slick Scottish granite the Steilacooms stayed stuck, my legs failing long before the grip on hand gave up. This grip is what Compass built the Steilacoom to deliver z- as a CX race tyre it lives to keep you shiny-side-up through twisty, off-camber, wet, grassy corners.

Descending at speed, swapping lines and surface materials across 4x4 tracks there was simply no hint of losing traction. Hitting 55kph on gravel was nothing but fun – no sign of sketchiness, or even the slightest concern. The longish 1045mm wheelbase of the test bike helped, but be of no doubt: the Steilacooms make you a better, faster descender than you deserve to be.

This is evidenced by the fact that at the time of writing I hold the Strava KOM for an 8km rocky gravel descent above Dunkeld that I wasn't even pushing that hard on. Put simply, I was having too much fun to care about remembering to go fast. On a highly mixed surface varying from protruding rock to drifts of gravel, to compressed clay and grass median strip, the Steilacooms let me range far and wide, transitioning from surface to surface with complete confidence.

The final 10k of the aforementioned Big Day Out (80km/1600m climbing) was on tarmac, but it didn't feel like a buzzy, draggy chore. The spacing of the knobs is such that although you know you're riding a knobbly tyre, it simply doesn't feel like it. Compass has tweaked the layout so that as you lean into a corner there's always the same amount of knob surface in contact with the road, so there's no transition from 'smooth' to 'knobbly' as with many other hybrid designs that seek to be fast-rolling yet capable in mud or gravel. With a supple casing and the right design, you can have a fast-rolling, mud-gripping tyre that also works on the road.

For me the proof in the on-road pudding is the other KOM I bagged on the Steilacooms: a 61-second all-out flat sprint on smooth tarmac. Averaging 45kph for the dash after a 40km hilly ride, the Steilacooms made an awesome high-pitched noise as I fanged along the straight. Just to prove it wasn't a fluke, I went back the next week and recorded exactly the same time to the second, again after a decent hilly off-road ride beforehand.

What further amazes me is that I had only just recently bagged that KOM when out testing the Compass Barlow Pass, the non-knobbly 38mm version of the Steilacoom. A few months apart, with no 'training' in between, the knobbly Steilacooms were 2 seconds faster over the 700m dash than the slick Barlow Pass – its 35mm sibling already one of the five lowest-rolling-resistance tyres in the world as measured by Tour Magazine.

Adding to the growing collection of amazeballs was getting a longer 4km KOM on the same road that I didn't know existed.

Another stunner: at about 430g per tyre, the knobbly Steilacooms are about 30g lighter on average than the slick Barlow Pass and the Schwalbe G-One 38mm. Compass explicitly states in a blog post that the Steilacoom is not intended for road use and that 'Efforts to make a knobby that rolls really well on the road are futile'. If this is its idea of futile, I'll have more please.

> Buyer's Guide: Tubeless tyres – all your options

Now not everyone is into Strava-gasms, and of course they are only of use in comparing with your younger self – you have no idea if anyone else was riding in a group, with a huge tailwind, etc. But I believe the evidence is irrefutable: the Steilacooms are up there with the fastest tyres in the world, on or off-road. I'm a huge fan of Schwalbe's G-one 38mm tyres – especially when they're on sale – but for the £10 extra money at RRP I'd go with the Compass option every time.

My one caveat here would be longevity. Of course it's pretty hard to tell over a month or so test period, but the rubber on the Steilacooms feels soft, and if you're mostly riding on the road they'd wear quickish I'd imagine. In that case I'd go for the Barlow Pass, which is likewise a ton o'fun on gravel.

The Steilacoom is for getting properly muddy-grassy-rocky, while still being able to burn along sealed roads without feeling like you're towing a photocopier in a wheelbarrow.

I'm now planning to get a set of extra wheels so I can quickly pick and choose between the Barlow Pass and the Steilacoom depending on route, weather and frame of mind. These to me are the only two tyres anyone needs, to cover every possible drop-bar-bike route option. If you're considering an alternative to a tubular tyre for CX racing, or considering a mixed on/off-road commute, tour or adventure, the Compass Steilacooms really should be top of your list of tyres to try.

Verdict

A frankly amazing combination of off-road grip, control and speed that translates well to the road for mixed rides