Will slightly loose headset cause shaking when braking?
I've noticed that when I apply the front brake to slow down and/or come to stop there is a shudder or shake that I can feel at the handlebar. The shudder is usually felt when braking at a fairly high speed or while going down an incline. Not sure if it's the front disc brake or a loose headset that's causing the shudder. The BB5 appears to be adjusted, and as far as the headset is concerned, I applied the front brake and did the back and forth rocking thing. It looks to be alright, but I don't know if it's a bit loose or not.
Anyone know if this is normal?
What forks are you running?
Marzocchi (all models as far as I know) have that loose bushing in the stanchion tubes that feels like the effects of a loose headset. Some older models of Fox forks also had this problem.
Putting too much air in either the positive or negative chambers of some forks will make the fork top out or bottom out - giving you a thunking sound similar to a loose headset.
It's a rigid mtb that I use for city riding. It has a Surly 1x1. I checked the headset earlier again and did the front braking and rocking it fore and aft. Should there be absolutely no movement at all when doing this? I lifted up the front and gave the steering a push to see if the front wheel leans to one side or not, and it seems the headset is more on the tight side than the loose side. Yet when I do the front and back rocking, I almost feel a slight movement, but I can't be sure if it's the rear wanting to move forward by the jerk. When I apply the rear brake also, then the bike feels solid. Normal? Am I doing something wrong?
There should be no movement in the headset when you rock the bike forwards and backwards with the front brake engaged.
Apply the process of elimination:
1. Check that the front wheel is mounted properly.
2. Check that the brake caliper(s) is/are bolted on securely and that there is no play in the pads.
3. Check the stem faceplate and steerer clamp.
If the clunking sound still persists, then it will be located in the headset:
4. Does the crown race fit securely onto the fork steerer (for non-split crown race versions)?
5. Does the crown race actually belong to the headset fitted? Some newbies don't bother to replace the old crown race when installing a different model of headset.
6. For non cartridge type bearing headsets, are the bearings the correct size and are they seated the right way up?
7. Is the headset retainer ring properly fitted? Note: Chris King and Woodman don't use the retaining ring system.
8. Is the frame head tube ovalised or cracked?
Last edited by standard3x; 05-23-2009 at 02:53 PM.
In addition to the suggestions made, the hub bearings may need to be serviced/adjusted as well.