Hookless Rim Info
Why choose one over the other?
Hooked Rims
Hooked rims are great for low volume / high pressure. This is going to be your road tires that are pumped up to 65PSI or more. As the air pressure increases and puts more pressure on the bead of the tire, having the hook to hold that bead in place is helpful. If you are planning on running over 65PSI, then you should choose a hooked rim.
Road Use
Road tires used at higher pressures have greater forces on the beads of the tire. If the tire has too much air pressure the bead can travel upward and the hook helps keep the tire securely in place
Tire Freedom
With a hookless road rim, you are forced into very specific tires, sizes, pressures, and conditions. If you get any one parameter wrong, the consequences can be disastrous.
Tire security
On higher pressures, an impact (like a rock or pothole) can spike the PSI due to reduced tire volume. This can lead to tire blowoff on a large impact
WHEN IS HOOKLESS RIGHT?
On larger volume tires that are found on gravel and mountain bikes, the pressure is much lower. Typically you are running less than 40PSI for gravel tires, and less than 25PSi for MTB tires. With this low tire pressure, there is no risk of overcoming the strength of the bead of the tire. In these cases running a hookless tire actually has benefits
Gravel / MTB Use
The hookless setup works great for gravel and MTB tires. This allows for a wider internal rim without adding extra rim material to the hook, resulting in a lower overall rim weight
Ease of Manufacturing
On carbon rims, the hooked profile presents complexities when manufacturing. While not impossible to overcome, the hooked rims do take longer to produce, and can have a higher scrap rate compared to the hookless counterparts
Improved Impact
With a hookless rim, the carbon fiber wraps around the top of the tire wall. This means there's not a very small hook that can be susceptible to rock strikes and damage. Rims themselves get stronger by being hookless.
What to choose
We prefer to choose hooked rims for all road purposes. While we know that there are people who can successfully run road tires on a hookless rim, it entails getting many parameters exactly correct. The potential of a catastrophic failure by getting any one of those parameters wrong is too risky for us to recommend road hookless.
For gravel and mountain bike wheels, Boyd Cycling was one of the first wheel companies to release hookless rims back in 2015.
If you are choosing a wheelset and you are going to swap both road and gravel tires on it, then you will want to choose the wheelset with a hooked rim profile.