Author Topic: Leaking Fork  (Read 1303 times)

Offline Brucie64

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Leaking Fork
« on: 05.07. 2010 13:08 »
I seem to have developed an oil leak from one of my forks, strange thing is it's leaking from the underneath where the fork leg actually joins the top yoke. Its enough of a leak for the oil to actually run down the back of the fork leg and spray onto the tank when moving.

Should there be an o-ring or seal present between the fork leg and the top yoke?
Bruce
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Offline a101960

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Re: Leaking Fork
« Reply #1 on: 05.07. 2010 14:03 »
Brucie,

Looks like you have the Eddie Dow dampers fitted to your forks in which case it is most likely that the leak is where the damper rod passes through the top nut. If this is the cases then fit a copper washer between the damper rod retaining nut and the fork top nut. If the leak is from the top nut itself then the most effective seal would be PTFE tape as used by plumbers. I have Dowe dampers fitted to my forks and I had the same problem, and strange to relate on one side only. It is also possible that the damper retaining nuts are lose and just need nipping up. You may or may not be reassured to know that this is not an uncommon problem especially if you have the aluminium top nuts. The stainless steel top nuts seem to be less prone to this problem. There is incidentally no oil seal fitted to the top of the forks.

John

Offline Brucie64

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Re: Leaking Fork
« Reply #2 on: 05.07. 2010 14:20 »
Hi John,

Interesting, I often wondered why my forks had dome nuts on top of the standard flat top nuts and other A10's I have seen about didn't!. Am I right in saying that Eddie Dow dampers had two way damping to reduce dive etc where as the standard dampers didn't?

The leak is definately coming from underneath where the fork leg joins the top yoke and not from the top nut/dome nut join. I shall take off the top nut tonight and try a little ptfe tape around the threads to try and seal it.
Bruce
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UK

Offline a101960

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Re: Leaking Fork
« Reply #3 on: 05.07. 2010 14:41 »
Brucie,

Yes, the Dowe fork dampers are indeed designed to facilitate two way damping. There is a valve located at the bottom of the rod which is in effect a piston with an enclosed ball bearing. For a full explanation of the set up look at this post. http://www.a7a10.net/forum/index.php/topic,2895.msg19476/topicseen.html#msg19476. A picture as they say is worth more than a thousand words.

John