I know we said we'd need a breather but people have been pounding us with questions, and one of the bigger questions people have had has been hooked versus hookless beads. This is especially relevant right now as Enve has just announced their Foundation series, which feature hookless rims.
First, to define. Hooked beads are the traditional clincher style, with a small inward facing protrusion around the out perimeter of the rim. Most of the wheels you've ever owned are hooked. Hookless have existed for quite a long time, so I am told, but have become more and more popular recently. Why?
There are three reasons, sometimes blending into one. Hookless carbon rims are much easier to manufacture. Molding the hood into a carbon rim is a bit of a pain in the butt, requiring more complicated molds and more labor, plus a greater chance of stuffing it up. Mountain bike rims, with their lower pressures, starting going hookless a while ago when people realized that not only were they easier and less costly to manufacture, you could put some extra meat at the outer edge of the rim where the hook used to be. Greater impact defense.
The rims pictured above, which are a HED Eroica at top and a White Industries G25A immediately above here, show a hooked and hookless bead. Since hooked aluminum rims have none of the construction challenges of hooked carbon rims, I wondered in my review of the G25A why they'd done it that way. And I still don't know.
Enve has also promoted the more aerodynamic tire interface that they find with hookless rims. The hookless bead deflects the tire's sidewall less, which allow for a smoother transition between rim and tire, a la below.
One issue that arises with hookless beads is that the hook provides tire retention security, and if you take that away you have to regain tire security somewhere else. For most, this is found in using tubeless tires. I'm not aware of any that preclude using tubes with your tubeless tires, but the non-stretch construction and shaping of tubeless beads are what these rims are after. But then what you have is a tire compatibility chart, and with the rate at which tires hit the market, someone's got a full time job keeping up with that. Based on our decade in the biz, buying stuff that you can't use with other stuff is not the most attractive of ideologies.
Now the wrinkle is that the more astute followers among you will know that I've been an advocate for hookless. We saw some issues with hooked carbon rims in the past, and it just seemed that the construction techniques afforded by hookless were the way forward there. But now we haven't seen a hook problem (knock wood) since forever.
One "ask me anything" asker was curious about the All Road 23 being a hookless bead versus the All Road 38 and All Road 50 which have hooks. Notice that I didn't hot link the All Road 23. Despite our thinking that a really light, shallow, wide All Road rim is an attractive thing, there was basically no uptake on the product. And a big part of that was likely the tire limitations that we had to put on them. We didn't get tires to blow off of them at 80 psi, but we couldn't exhaustively test tires, and we are really really conservative with this stuff. No one wants to ride a 28mm tire at 100psi, which is still wayyyyy below what a hooked All Road 38 or 50 rim is going to carry, but people might want to use a 30mm tire at 60 or 70. People do strange things, and tires heat up in hot cars, and tire pressure gauges are inaccurate, and blah blah blah.
For mountain bikes, hookless. Use whatever tire, there's no problem. But for road and in between, it's more murky. The future may not have any hooks at all, I don't know. But absent any hint of carbon hook construction issues, and with the low low payback of potentially really marginal aerodynamic gain, and with the pain in the butt of needing to babysit a rim's interaction with every tire that comes on the market, we think that the "not mountain biking" part of our ecosystem is better off with hooks for the foreseeable future.
There's been a ton of interest in both the rollyourown program and the wheel build interactive stuff.
Thank you again for all the questions and comments, we will hope to keep this going as well and as long as possible. Our video experiments are coming along so the interactive wheel build session is progressing.
Stay safe and have a nice weekend.