What is the point of head tube extensions?

[boomforeal]

I’ve noticed some otherwise traditional steel road bike frames/models with head tubes that extend an inch or more above the top tube. Eg. some pegorettis and that pretty AR in the custom photo thread. What is the point of this, rather than just having a longer seat/head tube? I’m thinking the lower top tube makes them easier to mount/dismount, like a compact frame, but with a more traditional profile.

[prototoast]

Functionally, it's basically the same reason as a sloping top tube, but some people prefer the aesthetics of one over the other.

[ElvisMerckx]

Beats a stack of spacers and/or a steep angled stem.

[fourflys]

short-legged people who need the bars a bit higher than a full race bike.. I think they are a fantastic revelation that most riders should probably adopt (or an upsloping tt/taller HT)..

[Jiminyt]

You can only run so many spacers above a headset on a carbon fork, typically 40mm. A head tube extension allows greater stack with proper support for a carbon steerer tube.

[mtbmoose]

It’s for those of us who aren’t as flexible as they used to be.

[Dude]

It’s so you can have a taller headtube without impacting the standover height. A taller HT means a level top tube would have to come up as well changing the stand over height. The other option is to have a tall headtube and angle the top tube “down” to the seattube. The other other option is to just have a ht extension and not daft around with the top tube at all.

[boomforeal]

Thanks y’all.

[Nomadmax]

Urs Freuler

[Marvinlungwitz]

Indurain was another tall rider who sometimes rode a bike with an extended head tube. In those cases, it was ostensibly for weight savings and to maintain frame stiffness.

Changes in stems & headsets (less stack) might have something to do with it nowadays, too.

[fignon's barber]

Originally Posted by Nomadmax

Urs Freuler

More of a Reverse Freuler.

[C40_guy]

Originally Posted by mtbmoose

It’s for those of us who aren’t as flexible as they used to be.

That will be *most* of us at some point in the future.

[Nomadmax]

Originally Posted by fignon's barber

More of a Reverse Freuler.

I might go with a "retrofit Freuler", but not reverse.

[bigbill]

Pegoretti did it for frames bigger than a 57. My BLE has a 59cm top tube and a 60cm seat tube. Bottom bracket to top tube is 57cm c-c measure on the seat tube. If I extrapolate a level top tube intersecting the seat tube at 60cm, the extended head tube is no longer a thing. Pegoretti said he did that to lower the weight and add stiffness to large frames. I'm not sure about the weight, but I understand the stiffness.

[MikeD]

Originally Posted by ElvisMerckx

Beats a stack of spacers and/or a steep angled stem.

Exactly. It's mostly for people that like to get their handlebars higher than the seat.