Clunk goes the forks

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Due respect but wrong, the damper length prevents the bush's from touching.

When the top nut is removed the damper rod is some distance down the stanchion, Check the underside of the alloy damper cap,you will see a ring where the original valve as hit it,
Regards J Lansdowne
xbacksideslider said:
The slider bushings and the staunchion tube stops SHOULD be the mechanical stop for fork extension, NOT the damper rods.

Of course, short of that mechanical stop, the damping system SHOULD engage and provide a hydraulic soft stop before that absolute mechanical stop.

Small diameter damper rods can handle dampened tension. They should not be subjected to impact tension.

It's a good thing wheelies are not favored by those who ride these bikes.
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john robert bould said:
Due respect but wrong, the damper length prevents the bush's from touching.

When the top nut is removed the damper rod is some distance down the stanchion, Check the underside of the alloy damper cap,you will see a ring where the original valve as hit it,
Regards J Lansdowne
xbacksideslider said:
The slider bushings and the staunchion tube stops SHOULD be the mechanical stop for fork extension, NOT the damper rods.

Of course, short of that mechanical stop, the damping system SHOULD engage and provide a hydraulic soft stop before that absolute mechanical stop.

Small diameter damper rods can handle dampened tension. They should not be subjected to impact tension.

It's a good thing wheelies are not favored by those who ride these bikes.
Click to expand...
Click to expand...

I am pretty cetain that the damper rods actually screw into the fork top bolt ??.
 
Been following this post because I was hearing similar noises coming from my front. Well I was changing my front tire and while I had it off I followed someones suggestion and put a little dab of silicone on the back side of my disk brake pads. Been riding it and the clunking is gone. Not going to stop me from putting the lansdowns in though! Cheers!
 
I haven't been sitting around - I must have had the forks apart and together now at least 5 times. At the suggestion of John at Lansdowne and Phil Radford, I finally tried loctiting the lower steel bushes to the stanchions. That seems to have fixed it. I only found between .007 and 0.010" of lateral movement of the bush - between the stanchion shoulder and the circlip. That really shouldn't have been responsible for the clunk, but the proof is in the pudding.

I also found a bit of wear (about 0.0015" over the limit ) in the middle of the right slider bore - right about where the disk brake mounts. I assume this is the result of braking forces on that side inducing a bit more wear. But I have a hard time believing this amount of slop induced that kind of klunk either.

Anyhow, I carefully resembled everything, filled with 150cc of 10wt and set the dampers to two turns out and amazingly - no klunk. At this point I have to assume it was something about the steel bushes.

What a joy to ride when everything works as it should.

What a lot of work to keep it that way.

Thanks to everyone for your suggestions, it really helped get through this and a special thanks to John for his invaluable insights throughout this project.
 
David . GOOD MAN! your persistance paid off!. if it was the bottom bush "slide hammering" producing a clonk that loud...the bush must have been tight in the slider.....10 thou movement seems a little amount to produce such a noise,,,but its gone by bonding it in place....so what must we conclude? Happy riding ,John Lansdowne Eng
napanorton said:
I haven't been sitting around - I must have had the forks apart and together now at least 5 times. At the suggestion of John at Lansdowne and Phil Radford, I finally tried loctiting the lower steel bushes to the stanchions. That seems to have fixed it. I only found between .007 and 0.010" of lateral movement of the bush - between the stanchion shoulder and the circlip. That really shouldn't have been responsible for the clunk, but the proof is in the pudding.

I also found a bit of wear (about 0.0015" over the limit ) in the middle of the right slider bore - right about where the disk brake mounts. I assume this is the result of braking forces on that side inducing a bit more wear. But I have a hard time believing this amount of slop induced that kind of klunk either.

Anyhow, I carefully resembled everything, filled with 150cc of 10wt and set the dampers to two turns out and amazingly - no klunk. At this point I have to assume it was something about the steel bushes.

What a joy to ride when everything works as it should.

What a lot of work to keep it that way.

Thanks to everyone for your suggestions, it really helped get through this and a special thanks to John for his invaluable insights throughout this project.
Click to expand...
 
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