on Cross bikes? 😕
not sure but I had it in bucket loads on saturday 😆
By any chance is this a bike with canti brakes and the cable running from the stem to the brake?
If so it could be because the fork is flexing and this is varying the tension in the brake cable.
Try one of these fork mounted hangers instead
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Well, in the motorbike world, 'chatter' is a bit of a black art, but usually connected with the frame and/or forks being too stiff.
I'd imagine it's a different thing in cycling though?
Why?
Because companies sell products that they can't be bothered to check if they actually work.
i cannot run one of the swan neck jobbies from the fork due to my staddle yoke.
so, do you think it happend due to the frame/fork being to stiff or too flexy?
If it's happening under brakes it's highly likely to be flex in the fork - possibly the stem, but less likely to flex enough to cause chatter. If you have a set of mini-Vs, try them to see if the problem continues (there is no exposed run of the cable).
Making sure your brake shoes are properly toed in is another possible fix.
Bear in mind in the motorbike world there is (or was) a school of thought that blames fork chatter on the rear end of the bike.
An unlikely but possible scenario is a cracked fork, but in that case the chatter would be getting progressively worse and fairly obvious. Back in the days of ultra light steel frames we used to whack a piece of ash broom handle up the steerer to stiffen it.