Originally Posted by
Kontact
This isn't a physics problem, it's a hardware problem. Stem risers clamp on the steerer in a different way than stems do. I have yet to see a stem riser that is approved by the riser manufacturer for carbon. They all tend to pinch at the bottom rather than clamp along the length of the exposed steerer like a stem does. And that is because the split ends shortly above the top clamping bolt, preventing the top bolt from closing the upper part of the tube the same way the bottom bolt does. Net result is that the bottom edge digs into soft carbon instead of conforming to a steel tube.
That's the problem with theories - they don't really apply if you don't understand the actual mechanics. And then you are making dumb recommendations on bike forums that could get people hurt. So maybe your ability to do basic physics has little application to actually working on bikes and giving advice?
Don't understand the hostility. Guess that is just your nature.
As to your statements, yes, real high school level physics. But a very condescending thing to say to someone trying to understand.
As for how a stem riser attaches to a stem, and if this is going to cause another apoplexy than please, just stop reading and block me, but I don't follow your reasoning. The few I have used all attach at the top of the tube in exactly the same fashion as a stem. They have a stop about an inch or two in, require spacers, have provisions for pretensioning, and clamp with two clamping bolts along the length of insertion the same as a stem. None I have used have a sharp lower edge.
found this interesting. An explanation without all the drama
I Want To Increase My Bike Handlebar Height: Are Stem Risers Safe? (easymountainbiking.com)