Wobbling fork on a Trident

[mateusz]

The fork of my Thorn Trident wobbles when braking, regardless of the load (it does so even when I ride solo on it). It was like this right from the start. Not really sure if anything can be done about it, but it does not look like a front brake adjustment problem - the whole fork does an oscilating front-aft movement when applying the front brake. No squeals. It is annying, uncomfortable enough to make me use primarily rear brake, the opposite of what I normally do. Any suggestions?

[expr]

Hello,

sounds possibly like the headset bearings require adjustment or replacement. can you tell me at the top of the handle bar stem looking directly down do you see a cap head screw (Allen key) along with one or possibly two more Allen key screws on the side of the stem.

Do you know how to set up the ( A-HEAD SET )

Undo/ loosen  the side one / or two Allen screws on the stem, loosen the top Allen screw move the handle bars from side to side to allow the stem to swivel free.

Line up the stem with the front tyre ( This is best done straddling the top bar) hold the handle bars as normal with the front brake on and rock the bike forward and back this will make the forks move back and forth, now adjust the top Allen screw that can be seen from directly above (CLOCKWISE) UNTILL ALL THE WOBBLE HAS JUST GONE.   Do not over tighten this screw, this is to preload/ take out the slack from the bearings only> once the wobble has gone, tighten the one/ two side Allen screws to complete the job these need to be fairly tight.

Dave.

[mateusz]

It is a very old thread, I know...
The headset was indeed maladjusted; the reason was that there were not enough spacers for the long steerer tube. After getting that right, the wobble is smaller, but still present.

[expr]

Glad you managed to sort it, all the best.


Dave.