Clutch judder

[Peter Naulls]

The clutch on my special has been developing a judder when changing down and also getting increasingly sharp when taking off from rest. Over the past few hundred miles it has become almost intolerable. 

When I heard debris being hurled around in the flywheel area I took the gearbox out expecting to find something obviously amiss however everything looks fine. Apart from a couple of thou movement in the rivets holding the splined boss I can find nothing wrong at all. Incidentally the pinion bearings are newish and the UJs look good. I haven't yet taken the flywheel off and haven't found the debris.

It's a 4 speed box and the clutch-type with linings on the flywheel and cover plate.

Where should I be looking for wear or problems? Clutch levers perhaps?

[Howard Wright]

Hi Peter

You seem to have covered most bases but other things I would check….

The clutch release bearing (whirring noises) and the torque tube bracket (often the cause of judder)

Cheers

Howard

[Peter Naulls]

Thank you Howard. The release bearing feels smooth enough but is quite noisy so I'll change it anyway. The torque tube mounting is fine. Maybe it's just those loose rivets on the plate causing the judder.

[Bob Culver]

Loose rivets especially show as a clack clack as drive reverses when trying to creep along at low speeds in top gear.

[Peter Naulls]

Thank you Bob, yes, I understand what you mean. The loose rivets look like a red herring, though I will get them replaced whilst it's apart. 

I disassembled the clutch unit and found one of the levers to be very tight in it's post. Oddly two of the pivot pins were quite loose but the third had been poorly riveted in place. I think it had rotated and found a tight spot with the lever. A better post and pin would be a good idea but for now I've freed it off.

All going back together soon with my long-awaited close ratio box!