Do these suffer from judder when used on the road? Just fitted them to my inbred with slick tyres and disc brakes and there seems to be an awful lot of shudder. Headset, wheel, disc and caliper seem tight and it only seems to happen just as the wheel comes to a halt, is this normal?

Crown race installed correctly?

Crown race installed correctly?

I think so the forks seem to be secure, I’d have thought if the race was loose the problem the judder would appear throughout the braking process – having said that the crown race did go on quite easily.

More likely to be a brake issue – those forks are stiff as are they not?

Unless they are cracked I can’t imagine judder with that fork.

First thing is as above – Headset.

Otherwise, are the brake callipers and/or disk loose?

Pretty sure the headset is on tight, re-did it the other night, when checking in usual manner with front brake on there is no judder. The brakes look fairly secure as well.
May buy a new crown race and refit it all, might even go for a new headset (the one on it is a bit old) if someone can recommend a decent cheap one – it’s got an FSA orbit xl II on at present

Judder is a really odd one. You’ll only get judder when the resonance of braking force matches the longitudinal (forward/backward) resonant frequency of the forks system (fork legs to frame interation). Ideally there is no pulsing from brakes, however there always will be a small amount due to changing thickness, warping, surface area and friction levels of the discs, whereas pads are uniform.

So as a system, you can do a couple of things to reduce it. Either reduce the source (ideal as this cuts all vibration), or reduce the transmission (not ideal, as the wheel will still vibrate, just you won’t feel it so much).

Easy checks are headset, crown race, stem (clamped down hard enough to preload the bearings), suspension forks if fitted. But these are all normally transmission, not source.

I’d focus on the brake, clean the rotors, re bed in the brake, ensure caliper and rotor are fitted securely, if centrelock no play rotationally (don’t know why this would occur – no experience of centrelock). As you’ve said you’ve checked these, I’d just clean and re-bed the disc, worth a shot before splashing cash on new parts. I’d probably try a new disc first, especially if it’s old.

My only experience of judder was when fitting a new disc, which provoked massive judder at low speeds. Went back to the old disc, fine. Took a lot of bedding in, and disappated over time. Because it was one of those with slightly wavy patterns, I think it was causing the fluctuation in braking force, and happened to resonate with the rest of the forks. Now I don’t sense any vibration at all.

It’s easy to test whether the headset bearings are shot, I presume you’ve done that.

As above, I’d be inclined in the first part to focus on the brakes. Experiment with changing the pads/rotors, ideally from another bike/spares etc.

Thanks for the replies, I think I’ll start at the brakes and work my way up!

had exact same issue on a genesis IO with on one fork.

changed the brake rotor, sorted it straight away.

My On One forks used to with a worn rotor too-new rotor no judder.

Tried my wife’s front wheel and was noticably better so new rotor (or cheeky rotor swap – she’ll never notice 🙂 )

I had a similar problem when I fitted some On-One steel forks. Eventually cured it with some new brake pads. I think there’s a few potential sources of vibration and if one of these happens to hit a resonant frequency of the forks you’ll get judder. Suspension forks probably absorb them much better. Best of luck anyway.