hey guys,

Was looking at some wheels the other day and they appeared to have to bead hook.they were a carbon 29er clincher wheel but to my supprise there was a lack of bead hook?

whats the reason/benifit of this other than easier to manufacture?

surely this would promote tyre burps etc?

feed back appreciated

liam

What make where they?

Def not Tubs?

IIRC specialized have some new carbon rims with no bead hook. Cheaper to make and the tyres don’t seem to roll off…. Or so they say.

Do the specialised ones rely on a raised section by the sidewall like stans?

I think the specialized ones use the logic that rims started off as rolled sections of steel without bead hooks, then became extruded sections with bead hooks that allowed higher pressures in the tires without them blowing off. Now that tyres have much stronger/tighter beads the bead hook isn’t needed anymore.

Can’t see it burping more, that’s a sideways movement isn’t it? The bead hook just stops it stretching and blowing off the rim.

I saw a wee article on the Specialized ones, from Crankworks or Interbike maybe? Gist of it was “We just decided to find out what happens if you remove them. Nothing, is what happens. Turns out we all put them on our rims just because we always have”

thisisnotaspoon-valid point i can imagine tyre manufacturing has come on a long way.

so why has no one else followed suit?

I cant remember where i read this but im sure it was along the lines of the pressures alone involved in holding a tyre on the rim were enough to make it surplus to requirements

The bead hook is sort-of a backup – if the tyre bead isn’t exactly the right diameter, or stretches slightly, the hook catches it and ensures the tyre still beds properly.

Does not having bead hooks also mean that you can’t convert them to ghetto tubeless?

Old rims never had bead hooks (I still have some) The only PITA with them is if you get the tyre on a bit wonky you get high spots. The bead and hook system spreads the load.
Old rims with no hook had pressures of about 80 psi maximum. If you had a inner tube with a bulge (like you do sometimes) it would lift the tyre over the rim.
So you had a marker on the tyre to check it was seated correctly all round.