Front wheel shudder question?

[Slick]

I'm looking for possible causes to my Genesis Equilibrium front wheel shuddering whilst braking. It's definitely a new thing but I was on a steep downhill section and I was trying to keep the speed under strict control as there was quite a few hidden patches of thick ice, so I was probably breaking as hard and as long as I ever had previously. Can disc brakes react like this when overused or is there a more likely explanation?

 

[vickster]

It’s buckled?

 

[QFour]

I suppose if the disc has got very hot it could have a warp in it this would give you a judder as the disc keeps catching a pad on one side. Spin the wheel slowly by hand and see if you can feel it catching. Also check the attachment of the disc to the wheel and make sure all is tight. If all is well then I would have a look at the brake pads.

 

[Slick]

Mm, I suppose I could have missed it, but I did hit a huge pothole a few weeks back but thought I got away with it. I'll check the wheel again.

 

[raleighnut]

Contamination on the disc/pad. New pads and clean the disc with Methylated/Isopropyl Alcohol.

 

[Levo-Lon]

As above ,you can try brake cleaner , or lightly sanding the pads and disc with a fine grade wet and dry paper and re bed the pads.
New pads are cheap

 

[Lozz360]

Mm, I suppose I could have missed it, but I did hit a huge pothole a few weeks back but thought I got away with it. I'll check the wheel again.

I think the suggestion was that the disk could be buckled as opposed to the wheel.

 

[Slick]

I think the suggestion was that the disk could be buckled as opposed to the wheel.

From @vickster?

 

[Slick]

I've checked the rotation of both the wheel and disc. Nothing is buckled so maybe just the pads. I'll try a replacement set, which will probably need it's own thread.

 

[vickster]

From @vickster?

Either or

 

[graham bowers]

Probably worth checking the headset as well.

 

[Jody]

I've checked the rotation of both the wheel and disc. Nothing is buckled so maybe just the pads. I'll try a replacement set, which will probably need it's own thread.

What speed is it dong this and is it more of a pulse or a high frequency shudder/vibration

 

[Slick]

Very slow speed on quite a steep downhill section. Not too sure how to differentiate between pulse and high frequency but the whole wheel and fork seemed to be vibrating back and forth which was clearly visible as well as audible.

 

[Jody]

Very slow speed on quite a steep downhill section. Not too sure how to differentiate between pulse and high frequency but the whole wheel and fork seemed to be vibrating back and forth which was clearly visible as well as audible.

If the fork is visibly flexing and making a noise then the headset would be the first to look at as per Grahams suggestion. If the disc is warped or uneven wear then it would feel more like a pulse where every rotation of the wheel would feel like the brakes were squeezed a little harder and then released. This would be on the same part of the wheel every rotation. It can cause a loose headset to knock and also cause the fork to vibrate. Anything higher frequency would likely point towards the pads being contaminated, not aligned correctly or old and would sound a bit like a cow mooing up to a high pitch squeel. High frequency vibrations don't usually make the fork vibrate to the point where you can see it.

 

[Slick]

If the fork is visibly flexing and making a noise then the headset would be the first to look at as per Grahams suggestion. If the disc is warped or uneven wear then it would feel more like a pulse where every rotation of the wheel would feel like the brakes were squeezed a little harder and then released. This would be on the same part of the wheel every rotation. It can cause a loose headset to knock and also cause the fork to vibrate. Anything higher frequency would likely point towards the pads being contaminated, not aligned correctly or old and would sound a bit like a cow mooing up to a high pitch squeel. High frequency vibrations don't usually make the fork vibrate to the point where you can see it.

Nice, thanks. The forks were certainly vibrating along with the wheel, so sounds like the headset has somehow come loose.