Hendo252 

I'm a proud owner of a new-to-me 2010 Spesh Roubaix, and due to some neck issues I'd love to get the stem up an inch or so.

I've been contemplating some of the various riser/adjustable stems, when I ran across this "Headset Extender" on the Specialized site.
https://www.specialized.com/us/en/ftb...ender#features

Their description sounds great -- "Extends head tube to raise stem 40mm"

But it isn't clear to me from the photos exactly how it does it, and whether it will work with an already-cut steer tube.

Anybody know about these animals? Will it let me raise the stem 40mm above the already-cut steer tube? Or do I need to try my luck with Specialized tech support?

Thanks in advance! I'm guessing this will be in the "too good to be true" category, but I thought I'd ask.

-Tom in SoCal

mechBgon

It extends the frame's head tube, but you'll need a new fork.

Hendo252 

Thanks Mech -- I figured it was something like that.

Thanks for taking the time to read and comment.

fietsbob

maybe a steering tube extender. stem raiser will be better..

If you were, even ordering a new bike, they seem to cut the steerer tube to a size formula,
before it goes into the carton on the other side of the Pacific Rim.

mechBgon

The fork has a carbon steertube, so an extender would be quite risky. I advise getting a replacement fork if it comes to that. Compared to paying an oral surgeon to put one's teeth back in... yeah. A bargain.

byte_speed

I've got a steer tube extender (not using on carbon) and it bolts on just like a stem. Question: as long as you use a compression plug, what would be the danger?

fietsbob

Somebody was happy buying more bike than they actually needed
and were physically uncomfortable riding it , before too long, is My guess..

Perhaps adding another aluminum liner tube inside the carbon one will be a patch,
of course a Steel steerer carbon blade fork can be purchased can it not?

mechBgon

1. stem risers clamp to the end of the steertube. Best practice with carbon steerers is to place the stem at least one spacer down the stack, so it's not clamping to the exposed end of the steertube where it's easiest to start a crack. I know Specialized makes this less practical since they often use cammed stems that have to be at the top of the stack (and use their offset top cap), otherwise you get this:



2. stem risers add height and therefore they add leverage on the "focal point" of stress at the compression ring. The headtube extender doesn't, because it actually moves the upper bearing and compression ring up.

3. stem risers are designed quite stoutly (which isn't bad in itself) and the ones I've worked with would create a substantial stress riser at the slot as a result. Fine for metal, not good for carbon.


I've seen Roubaix steertubes cracked even with the factory stem. Best not to gamble, that's my position. I don't know if the 2010 Roubaix uses a recessed lower bearing (if so, that would be a proprietary Specialized fork) but if it doesn't, the Ritchey Comp carbon fork with an alloy steertube is a reasonably-priced option.