Jumping new hoops

Hyro on his stock 35 mm Schwalbe Super Swan knobby mud tires.

Hyro, my Giant TCX cyclocross bike, promised quiver-killing versatility years before gravel bikes became a trend. As per the UCI cyclocross regulations it’s built to, the 2014 TCX chassis can swallow a knobby, mud-plugging 33 mm tire with loads of space to spare; Giant’s PR materials officially state a 40 mm tire width limit, enough to float over gravel roads. The same frame can take 28 mm slicks and go on long road rides – something I’ve done time and time again.

That said, those promises are predicated on owning multiple wheelsets. While the TCX can accommodate many kinds of tires for all sorts of situations, having to swap them on and off just one wheelset will get old quickly. At the very least, a bike like Hyro needs two wheelsets to bring out his potential: one wheelset for road, and another for gravel riding, for example. That same potential was also brought into question by the bike industry, after three years of waffling about, finally settling on closed dropouts and 12 mm through-axles as a wheel installation method for road bikes with disc brakes.

Note the CenterLock brake rotor spline and internal-cam QR skewers on the CX75 hubs.

Originally, my plan for a second wheelset for Hyro involved Shimano’s CX75 hubs, which I’ve had in storage for a long time. These can be considered a straight upgrade item I could use with my existing rims, as they are also drilled for 28 spokes. These sport labyrinth seals for their angular contact “cup-and-cone” bearings – a good step up from Hyro’s stock hubs.

The problem with the CX75 hubs is that there is no way for them to work with a more modern disc-braked bike which has through-axles. With open dropouts nowhere near as widespread as they used to be, a wheelset built on these is effectively a dead end.

I was mulling over the parts I wanted for my desired wheelset, before and during COVID19 lockdown, when I came across a for-sale ad as I was absentmindedly browsing a local road cycling Facebook group. It’s as if someone read my mind: put up for sale was the exact item I was looking for.

Details blurred to protect seller’s identity.

I’ve heard great things about H Plus Son and its lineup of aluminum rims. The Archetype and TB14 rims, in particular, are part of many a wheel build. I would have gone for the Archetype had the company not announced the Hydra rim, which was essentially an Archetype rim shorn of its braking track, made slightly wider, and has tubeless tire compatibility baked in.

I met with the seller, made the transaction, and went home with a new-to-me, pre-loved wheelset. Gracias, seƱor!

Color, tubeless compatibility, and disc rotor fitment aside, this wheelset is very different from the stock Giant S-X2 hoops. For starters, these Hydra rims are drilled for 32 spokes instead of 28.

Each wheel sports a SRAM Centerline 160 mm brake rotor. These were supposedly made to keep the braking surface as straight as possible and resist warping.

With H Plus Son’s The Hydra rims on the outside, the 32 J-bend spokes are then laced, by the wheelbuilders of Gran Trail Cycles, to Novatec hubs – the D791SB up front, and the D792SB at the back. The latter has an 11-speed Shimano HG freehub body.

Straight off, these wheels were set up for fitment into a bike with closed dropouts and through-axles. Part of the seller’s bundle was a zip-lock bag with axle parts and end caps to convert the hubs to open-dropout use and quick-release (QR) skewers. That was the first thing I did.

Converting the rear hub is equivalent to taking it apart for servicing and bearing replacement. You use two wrenches to loosen the threaded end cap from the non-drive side of the axle, then take it apart from the sides. The four-pawl freehub body comes along for the ride.

With the freehub body removed, you can see the ratcheted inside of the hub shell, where the pawls catch to transfer your leg power to the wheels and into the ground. At the bottom sits one of the four cartridge bearings – this one a “6902RS” bearing.

Take the freehub body and seat it into the hub shell, then thread the QR axle through the hub and screw on the QR end cap on the non-drive side – job done. Don’t forget the grease and the QR skewer!

Converting the front hub is even easier: just pull off the two end caps from each end of the hub, and slide the QR end caps in. No axle tomfoolery needed.

One last preparation to do before making these wheels roadworthy is installing rim tape. I used Stan’s No Tubes tubeless rim tape for this job, making this a tubeless-ready wheelset in case I decide the technology is mature enough. For gearing, I went with another Shimano CS-HG700-11 cassette, and I mounted my tires on.

The wheelset I ended up with turned out better than my original plan in a number of ways. While it has eight total added spokes and foregoes CenterLock rotors in favor of six-bolt rotor fitment, it already has future-proof hubs so I can use it on a more modern road bike, and I saved quite a bit of money by going second-hand. While it’s no lightweight, I was able to weigh new and old front wheels back-to back with a luggage scale, with the new front wheel coming out 250 grams lighter.

What happens to the stock S-X2 wheelset? I’ll keep it, mainly for indoor training. I have a bunch of old tires I can use while slaving away on the turbo trainer is the most feasible and logical way to keep me riding.


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.