Fork Damper Bodies

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Nov 10, 2006
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This winter I decided I had to overhaul the fork dampers. On refitting I can't get the lower bolts to tighten as the damper bodies are turning inside the sliders. I'm sure there's only one fibre washer at the bottom of each slider as I had the dampers out years ago and they went straight back in no probs, Any ideas?

Thanks in advance,

There is no positive location for the damper bodies. I think that I would try fitting the main springs and top caps. The spring pre-load should be sufficient to hold the damper tight against the recess in the fork lower and stop it turning, assuming that the threads are good.
I second the previous post, but also make sure the bolt is not bottoming in the damper tube, with the correct washers fitted. Have you taken out the damper tube and run the bolt up into it on the bench to check? If it doesn't screw in freely, it can turn the damper tube. If you have the springs installed, that should allow you to hold the damper bodies against the bottom of the slider. It helps if the fibre washer is new and dry. I assume you are using the same bolts and the same dampers. I was caught out when I bought new alloy damper tubes, which have 5/16 x 26 tpi threads rather than 5/16 x 24 tpi threads.
Everything is fitted I even compressed the fork legs to increase the friction. Having slept on it I'm confident the the problem lies with the tapered seats in the bottom of the sliders. I reckon the flat base on the bottom of the damper is landing first and not allowing the taper to get a hold. I'm going to skim about 0.015" off the base and end of the taper and give it a go.
Daveh, I borrowed a pair of alloy dampers and yes they are BSF, they wouldn't nip either. It has to be the taper in the slider, I hope. Anyhow one's in the lathe waiting I'll report back.

Sorted back together.
Looks like the tapers in the bottom of the sliders had worn a little. I supose it's got to be expected with a 33 year old high mileage bike.

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