Motorcycle Repair: Honda Shadow 600, leaking fork seals, honda shadow 600

Question
Hello, five years ago I purchased a 1995 Honda Shadow in perfect condition from a friend of mine. After the first year on the streets, the front forks started leaking heavily and took the bike to a locally reknown motorbike mechanic and changed seals with original ones. After two short runs, the forks leaked again. Again to the mechanic for seals change and the same happens. We also changed the left fork tube [which leaked much more than the right one] with Honda originals but the forks, after a few kms, leaked again.To wrap it all up, I have changed the seals five times and the tube [left only] once, in 5 years. The renewed old fork tube was still in immaculate condition and no pittings or bending. What is your opinion please. Thanks.
P.S. At the moment I am running on leaky forks again.

Answer
Hi John,

You are not alone on leaking fork seals. It is common and the reasons
are many. The solution may lie in different areas depending on the
bike in question.

Often the seals are damaged during the install by the sharp tube edges.

Second, the internal brass colored bushings can get loose allowing the
tubes to wiggle in the lower fork holders.
You may be able to remove the wheel and pull forward and back on the
lower fork and see if it moves on the fork tube.

Sometimes people put too much oil in the fork, increasing oil pressure or too light of oil weight
for their bike's average load. Using a bit heavier oil may help if you used ATF
or light fork oil.

Make sure tubes are free of nicks or scratches and are not bent.

Check if the leaks are coming from inside the seals or outside the seals
due to a nicked seal cavity or seal not seating straight.

Sliding a thin plastic down the tube into the seal to clean and reseat it may help
especially if you ride in dusty areas or if you ride infrequently.

The forks should always be pumped a few times before tightening your front wheel axle,
this keeps things in better alignment without any binding.

Often it helps to use either original Honda parts or buy some SKF seals which often work well.

A front wheel or tire that is out of balance can wear forks and seals.

Some other possibilities are to use these on the tubes: http://www.sealsavers.com/

If you wash your bike often with pressure washers then that is the problem, they force
dirt into the seals every time and are a major cause of constant seal problems.

The ultimate last resort is to try another complete set of forks but this is not a sure thing either.

I would try cleaning them gently with some thin cellophane type film and work
it into the seals with some oil or grease, pull it out and ride awhile to see if the leaks stop.
It may be a good alternative to another full rebuild.

Some seals have a weak inner spring around the sealing area, you may be able to look
and see if the seals are even touching the fork tubes. If not then they are poor seals.
Get some SKF seals if possible.

Luck!
WS
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