[Mr. Versatile]

I can't keep the headset on my bike tight. I have a steel frame DeRosa, with an all carbon fork, (1" steerer). I adjust & tighten, then go for a ride of 25 + miles, and come home to find it loose again. It's getting a little frustrating to have to adjust & tighten the thing literally after every ride. Everything is the correct size, none of the pinch bolts are working their way loose. Anybody got any ideas?

 

[bigbill]

I can't keep the headset on my bike tight. I have a steel frame DeRosa, with an all carbon fork, (1" steerer). I adjust & tighten, then go for a ride of 25 + miles, and come home to find it loose again. It's getting a little frustrating to have to adjust & tighten the thing literally after every ride. Everything is the correct size, none of the pinch bolts are working their way loose. Anybody got any ideas?

Does the steerer come almost up to the top edge of your stem? If it doesn't you might not be getting an adequate clamp with the pinch bolts. I had the same problem you had and noticed that the pinch bolt gap was different between the lower and up bolt. Because I didn't have enough steerer in the stem, the upper bolt was pinching tighter and actually squeezing down on the steerer causing it to loosen frequently. To solve it, I sanded down a carbon spacer (aluminum would work as well) to about half of its original height. This put more steerer in the stem and solved my problem.

 

[achiral]

With a perennial loosening like this, it is possible that the headset is not fully tightened before the ride.

Are there any tight or loose spots as the handlebars are rotated? This would be indicative of uneven wear on either the bearings or races. This could cause apparent loosening (i.e. the headset is compressed in one of the tight spots. As the ride progresses, bearings rotate so that you see a loose spot.) It is also possible that there is internal wear or damage without any obvious indicators.

The compression plug you are using may be slipping and not allowing you to apply enough initial pressure to the headset. You wouldn't notice any problems initially, but they would manifest themselves after a couple of harsh bumps.

Has this problem been occurring ever since the fork/headset combo was installed? Or is this a problem that has just recently started?

 

[alienator]

What kind of fork? On some forks a less than square cut on the steerer can lead to repeated loosening of headset preload. Otherwise, I think the "steerer cut too short" might be the source of problems.

 

[rePhil]

Is this a new frame?

Is this a new frame or headset? I have seen a new installations where the cups weren't fully seated in the frame. During every ride the get pushed in enough to cause the headset to get loose.