annedonnelly
Girl from the North Country
- Location
- Blyth, Northumberland
That's what we did to mine - you've explained it perfectly.
Creaking handlebars
- Thread starter Andy in Germany
- Start date
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Ajax Bay
Guru
- Location
- East Devon
I wonder if the extreme angle you have set that adjustable stem at means that the stem fastenings are at an abnormal angle compared to the normal forces on a bar.
The maximum force on a bar is the 'up' force from the rider when pulling up a hill - ie vertical or a bit back from vertical. Normally the stem bolts (normal stem - say 7 degrees) will be roughly perpendicular to the direction of that force and maybe cope with the flexing caused by the forces without creaking.
You could experiment by dropping the adjustable stem down to horizontal (briefly - you've said you need it right up because of the slammed (short) fork steerer/stem interface) and see if that makes a difference.
But I'm with @Blue Hills's advice in the first instance.
The maximum force on a bar is the 'up' force from the rider when pulling up a hill - ie vertical or a bit back from vertical. Normally the stem bolts (normal stem - say 7 degrees) will be roughly perpendicular to the direction of that force and maybe cope with the flexing caused by the forces without creaking.
You could experiment by dropping the adjustable stem down to horizontal (briefly - you've said you need it right up because of the slammed (short) fork steerer/stem interface) and see if that makes a difference.
But I'm with @Blue Hills's advice in the first instance.
The problem with the adjustable stems I've seen was a bolt that "fixes" the angular position by going through a threaded clamp hole at the same side as the bolts head, with the bolts tip pressing on the tube wall the clamp is on.
When tensioning the bolt it exerts a pushing eachother away force between clamp and tube dead ends. That is the "fixing".
Poor, because nothing at the other side of the tube wall (alike a nut and required longer bolt would have been) tensions "through" the two mounted parts, holding them together that way. Any deformation of plate and tube causes wiggling room and deformation of the plate is precisely what happens when tensioning the bolt, and also the bolts tip grinds off material of the bar it pushes against.
On top of that problem, this plate has a number of horizontal ridges in order to give grip on the tube wall, which also has ridges. But when you cycle, you exert just like pedals, an alternating force left / right which wears the alloy sides away from the ridges, reduce even further their width, further aggravating the problem.
At some point I dumped the "adjustable" and the cyclical returns of creaking sound disappeared with it.
When tensioning the bolt it exerts a pushing eachother away force between clamp and tube dead ends. That is the "fixing".
Poor, because nothing at the other side of the tube wall (alike a nut and required longer bolt would have been) tensions "through" the two mounted parts, holding them together that way. Any deformation of plate and tube causes wiggling room and deformation of the plate is precisely what happens when tensioning the bolt, and also the bolts tip grinds off material of the bar it pushes against.
On top of that problem, this plate has a number of horizontal ridges in order to give grip on the tube wall, which also has ridges. But when you cycle, you exert just like pedals, an alternating force left / right which wears the alloy sides away from the ridges, reduce even further their width, further aggravating the problem.
At some point I dumped the "adjustable" and the cyclical returns of creaking sound disappeared with it.
Ajax Bay
Guru
- Location
- East Devon
You're dead right that the ridge interface that the adjustable angle joint needs is also its weakest link. That interface has less area than the similar one on many seatposts but has to cope with far larger moments.
