Clunky front fork.

[Mark]

Hi all.
This a second hand set of marzocchi forks that I’ve fitted to a 350 I’m putting back together.
They appear straight and true, chrome good.
There’s a clunking coming from them when operated, mainly on the rebound. I’ve had a peep inside and pulled out the springs and spacers to see if anything obvious was afoot, but even with these components removed the clunking is still there. It’s difficult to ascertain if it’s one or both of the forks and I don’t think it’s the head bearings as they have been repacked and tightened down and there’s no discernable movement when pulling or pushing the front wheel.
I’ve not done a fork rebuild before so thought I’d ask here before I go further.

Any ideas?

Thanks, Mark.

[Ming]

Can't help - I have a similar problem on a K2 Sport. It's a noticeable 'clunk' / judder on braking. It spoils the bike at the moment so I'll watch with interest. I've had the forks apart, cleaned them and reassembled / refilled, nothing untoward spotted.

[EVguru]

From an ATG a very long time ago..
https://photos.app.goo.gl/JL9tV392cmgjic8XA
https://photos.app.goo.gl/JEdEPJ52B6qaLBJy5

[Ming]

I finally got round to trying the mod as suggested by Paul back in May. I had an old pair of dampers which I have modified as per the instructions, so finally dismantled the K2 forks. What I found was a different set-up in the K2.

Dampers2.JPG (457.66 KiB) Viewed 2884 times

Modified 'old' damper top, 'new' K2 damper bottom. Differences are drilling diameters at the bottom (5mm cf 4.5mm), no drilling at the top on the K2 units, more robust plastic rings on the K2 units, better finish to the top of the K2 dampers and the fixing bolt of the K2 dampers is a smaller diameter, though shouldered to the same diameter as the older versions.
Anway, I've fitted the modded ones to see if there is any improvement in the harshness I experienced. Reassembly tomorrow and then see how they are.