I was thinking of getting a new carbon bar and double checked my bikes (2022 allez sprint) manual and randomly saw that specialized says no more than 5mm of spacers above stem.
It’s a carbon fork on a specialized allez. The bike shop cut it originally a bit and I rode it halfway with spacers. After a fit, the fitter slammed it and I’ve had no fit problems. But now I’m thinking have I been riding with a sheer off risk? This does have the expander plug but I think it’s just the factory one that came with the bike. A specialized authorized LBS built up the bike.
If so I’m gonna order a cut guide and cut this thing because I’m going to build up a new bike anyways. Still going to use this bike in some rides so I think I should cut this.
But I see a lot of people riding with chimneys/stovepipes. Are we all just an accident waiting to happen?
by HellaReyna
11 Comments
Can’t edit but as you can clearly see, there’s approx 37mm of spacers above the stem.
Yes, that is usually a bad idea. The expander plug should be able to support the clamping height of the stem and ideally the headset area as well. Unless you have a super long expander, it won’t be able to do that.
It is unsafe in the sense that if your crash, that is a bad place to hit.
If the fit is good, change the handlebars and cut the whole excess above the handlebars off. No need for it anymore.
Check the mechanics manual.
It shouldn’t be a structural issue as long as you can still preload the headset correctly and don’t over-tighten the expansion plug.
I guess there is some more risk of bashing your chest or face into the top of a tall stovepipe 🙂
Generally, on carbon steerer tubes, I recommend leaving a slight bit of tube above the stem top and using one spacer on top. This provides the most clamping area for the stem and reduces the risk of cracking the steerer tube 🙂
If it is a carbon steerer, remember to use an appropriate blade when cutting. I recommend a carbide grit blade.
You need to cut it. It’s ok to do this for a fitting and maybe a week until you are sure the fit is right for you, but then it’s time to cut the tube down to specs. All Specalized bikes I’ve owned so far have this 5mm limitation written in the manual.
My spleen already hurts when I see that.
It’s OKAY – for a short time while you test the bike out – before cutting the steerer, but not long-term due to lack of inner support from the plug that deep into the tube.
Specialized makes an extended length expanded plug for just this, it’s like 20 bucks, and well worth it
There is no unsafe amount ABOVE a stem unless you are talking about taking it in the chest. That could be uncomfortable in a crash.
Your fork manufacturer should tell you.
Some forks can handle that. Other’s probably can’t
If you think of what you have there as a nice projectile waiting to bury its self in your chest if things go wrong you will understand why they say no more than 5mm.