Adjusting handlebar stem

beaumont7

I have an alu/carbon road bike which has a carbon bar stem. I would like to raise the bars a little to ease my position on the bike. I can loosen the allen screw in the top of the stem but the stem does not loosen. i have tried tapping it with a wooden mallet but to no effect. Any ideas of what I can do next? Should I try a little WD40 on the stem where iyt enters the headset or down the top of the allen screw so that it can seep down to the locking machanism? Would this have any effect on the carbon stem?

nicklouse

nooo

you will need to change or flip the stem over.

see this

http://www.bikeradar.com/forum/viewtopic.php?t=12689155

the stem pinch bolts hold it al together and the top cap bolt only preloads the bearings.

the top of the steerer must be above the top pinch bolt.

desweller

It's not an old fashioned quill stem. Unfortunately, you can't just loosen the top screw and move it up and down like the old days. Modern stems are clamped to the outside of the unthreaded steerer tube by the two pinch bolts at the back of the stem. The top screw is just used to take up vertical play in the assembly before tightening the pinch bolts, it's NOT used to set stem position.

Modern stems have their position set by use of spacers between the stem and the top bearing. In your case this does unfortunately mean that, if there are no spacers above the stem, you are somewhat limited in your options for raising the height of your bars.

If your stem is angled (i.e. it does not stick out at right angles from the steerer tube) and it is currently arranged so that it's pointing downwards, you will be able to flip the stem to achieve a height increase. Other than that, it's new stem time.