What scares you about it? Before doing it I would try to get a good bikefit to make sure it is the right setup for you. Don’t forget to use a really small teeth saw and use a mask and eye protection too. Carbon dust is extremely toxic.
tedontwo on
Don’t cut it, stack donuts on it for ride fueling.
flycharliegolf on
“Is that your uncut steerer or are you just happy to see me?”
OhioHard on
I like my teeth where they are, thank you very much
Aututto on
Gotta sit somewhere on your breaks
Flowech on
PNS jokes are getting out of hand
allouttaideals on
I thought I was on /r/bicyclecirclejerk for a moment.
murkyotters on
That thing is waiting to impale you
Tyforde6 on
For when you get your best mate a ride on your handlebars.
MariachiArchery on
I saw someone here call it a coward tower recently and I thought that was funny.
u/OhioHard has a good point here, its a joke, but actually means something important. With your steerer tube this long, your gap expander, compression plug, whatever you call it, is not working to support the hoop stresses being applied to your steerer tube by the stem clamp. Which, is a safety critical aspect of the way these CF bikes are constructed and assembled.
You *need* that compression plug acting to support the clamping force of the stem. With this many spacers above the stem, it can’t do that. So, you should cut your steerer tube.
A general rule of thumb for CF steerer tubes is that you should have no more than 30mm of spacers. This is because of the cantilever structure that is your stem attached to the steerer tube, and headset. The further away that stem is from the fixing point of the cantilever structure (the upper bearing here), the greater the forces exerted are amplified on the cantilever beam (the steerer tube here). So, we need to limit that distance, to decrease force amplification on the beam here, the steerer tube.
So, plop 30 spacers under that stem, the maximum, and cut it. You can dial it in later. There is no scenario where riding your bike with this much additional stack would be safe. Get it down to the maximum, 30mm.
Edit: the point being, your steerer tube can snap and you’ll lose your teeth. To help illustrate, do the following.
Go find your self a wooden yard stick. Right? Then, place it over the edge of a table and fix it to the table. You can just hold it down with your hand. Now, overhang that yard stick 20 inches over the edge of your table, and push down on the furthest end away from the fixing point, the edge of the table. Do you follow? Push down on the edge of the yard stick that is overhanging the table and hold the bit that is on the table flat onto the table.
Its super easy to bend, isn’t it. You can bend the yard stick over the edge of the table no problem, by applying very little force.
No, change your overhang to 3 inches and repeat the experiment. Its nearly impossible to bend, even with a lot more force, isn’t it.
That is the same thing happening here.
YouNeedToSignUp on
cut it or it will kill your fork. The steerer plug acts against the clamping pressure of your stem. Cut it now
Tits_And_Ash on
Just think about it Impaling your chest, that’s fairly motivational
Lanky-Fee7124 on
I’d be too scared to ride that bike like this, honestly.
oldbonhomme on
Leave 1/2 inch for wiggle room in the future.
slashkehrin on
Watch this actually be an aero gain…
owlpellet on
Size bike to preferred fit. Estimate planned lifespan of fork and add 5mm top spacer for every ten years.
The bike doesn’t age, but you will.
Pay a shop to cut it.
the_kodeman on
Can I sit on your handlebars? uwu
therealskr213 on
If a slammed stem is the right fit, cut it. If you’re not sure if it’s the right fit, then it’s not the right fit.
ShowdownPhil on
If you don’t know 100% you want to slam your stem, you don’t slam your stem.
Throw some spacers in under there, cut it high, and ride if to a month or two. Only then, if you feel you want it lower, start bringing the stack down incrementaly.
22 Comments
What scares you about it? Before doing it I would try to get a good bikefit to make sure it is the right setup for you. Don’t forget to use a really small teeth saw and use a mask and eye protection too. Carbon dust is extremely toxic.
Don’t cut it, stack donuts on it for ride fueling.
“Is that your uncut steerer or are you just happy to see me?”
I like my teeth where they are, thank you very much
Gotta sit somewhere on your breaks
PNS jokes are getting out of hand
I thought I was on /r/bicyclecirclejerk for a moment.
That thing is waiting to impale you
For when you get your best mate a ride on your handlebars.
I saw someone here call it a coward tower recently and I thought that was funny.
u/OhioHard has a good point here, its a joke, but actually means something important. With your steerer tube this long, your gap expander, compression plug, whatever you call it, is not working to support the hoop stresses being applied to your steerer tube by the stem clamp. Which, is a safety critical aspect of the way these CF bikes are constructed and assembled.
You *need* that compression plug acting to support the clamping force of the stem. With this many spacers above the stem, it can’t do that. So, you should cut your steerer tube.
A general rule of thumb for CF steerer tubes is that you should have no more than 30mm of spacers. This is because of the cantilever structure that is your stem attached to the steerer tube, and headset. The further away that stem is from the fixing point of the cantilever structure (the upper bearing here), the greater the forces exerted are amplified on the cantilever beam (the steerer tube here). So, we need to limit that distance, to decrease force amplification on the beam here, the steerer tube.
So, plop 30 spacers under that stem, the maximum, and cut it. You can dial it in later. There is no scenario where riding your bike with this much additional stack would be safe. Get it down to the maximum, 30mm.
Edit: the point being, your steerer tube can snap and you’ll lose your teeth. To help illustrate, do the following.
Go find your self a wooden yard stick. Right? Then, place it over the edge of a table and fix it to the table. You can just hold it down with your hand. Now, overhang that yard stick 20 inches over the edge of your table, and push down on the furthest end away from the fixing point, the edge of the table. Do you follow? Push down on the edge of the yard stick that is overhanging the table and hold the bit that is on the table flat onto the table.
Its super easy to bend, isn’t it. You can bend the yard stick over the edge of the table no problem, by applying very little force.
No, change your overhang to 3 inches and repeat the experiment. Its nearly impossible to bend, even with a lot more force, isn’t it.
That is the same thing happening here.
cut it or it will kill your fork. The steerer plug acts against the clamping pressure of your stem. Cut it now
Just think about it Impaling your chest, that’s fairly motivational
I’d be too scared to ride that bike like this, honestly.
Leave 1/2 inch for wiggle room in the future.
Watch this actually be an aero gain…
Size bike to preferred fit. Estimate planned lifespan of fork and add 5mm top spacer for every ten years.
The bike doesn’t age, but you will.
Pay a shop to cut it.
Can I sit on your handlebars? uwu
If a slammed stem is the right fit, cut it. If you’re not sure if it’s the right fit, then it’s not the right fit.
If you don’t know 100% you want to slam your stem, you don’t slam your stem.
Throw some spacers in under there, cut it high, and ride if to a month or two. Only then, if you feel you want it lower, start bringing the stack down incrementaly.
Get a steering wheel from a bus.
Tandem bicycle
Fill it up with water, sip as you go