Leery of clamping that delicate carbon fiber frame in your repair stand? Well, you should be as carbon frame tubes should never be clamped directly. That said, clamping the seatpost isn't always an option, either, and the folks at upstart company Hirobel have introduced their novel Carbon Frame Clamp adapter to fill the void.
Instead of directly clamping the bike – or any part of it – with some sort of rigid jaws as is normally the case, the Carbon Frame Clamp uses a combination of grooved soft rubber wheels and stout rubber straps that hold the bike at the seat cluster and head tube area. According to Hirobel, this distributes load across a broader area than merely clamping a seatpost as is the norm, plus the grooved wheels are meant to be positioned at the seat cluster and head tube area, where the tube walls are usually thicker and more durable than in the middle of a tube.
Carbon frames should never be clamped directly, and it isn't always best to grab the seatpost. Hirobel presents another option with the Carbon Frame Clamp
The attachment method is not unlike setups used on many automobile racks and is designed to be similarly gentle, plus it's easy to mount bikes on to the Carbon Frame Clamp (which works fine on metal frames, by the way). Moreover, Hirobel has designed the Carbon Frame Clamp's octagonal crossbar to work in most repair stand jaws.
"Our clamp takes the weight of the bike right away, so the mechanic is not holding the weight of the bike while trying to adjust the clamp to the seatpost," said Hirobel co-founder Marc Bellett. "This has been a huge advantage for us not only in the shop where all sorts of different shapes/sizes come through, but also working rides/races where bike turnover in the clamp is very high.
The attachment method is surprisingly sturdy
"By clamping inside the triangle, we are also able to eliminate the spin that can happen when the seatpost isn't clamped tightly enough (at least for round posts). Clamping by the seatpost can be problematic as well when applying high torque. We have seen seatposts pop through seat tubes from the pressure of changing a bottom bracket when clamped that way."
We just took delivery of one of Hirobel's Carbon Frame Clamp prototype and it's much sturdier and more substantial than we had expected given the written description. For sure, the system of relatively soft rubber wheels and straps has a bit more 'give' than more rigid attachments but so far, it's proven stout enough for some hardcore wrenching.
The Hirobel Carbon Frame Clamp is designed to work in nearly any repair stand
Although the system is primarily intended for carbon road frames (or any chassis with a fairly conventional front triangle), it seems quite adaptable to several full-suspension mountain bike frames we've tried, too. Notably, we've found it handy for some trail and enduro machines with dropper posts that we'd prefer not to clamp directly and despite our initial reservations, we've had no issues so far with flipping even heavier bikes upside down without having to reposition the Carbon Frame Clamp's straps or rubber wheels.
Hirobel hopes to bring the Carbon Frame Clamp to market before the end of the year with a retail price of US$249. It's still in the crowdfunding stage for the time being, however, but supporters can potentially get a Carbon Frame Clamp for US$200 through Hirobel's Kickstarter page.