One of my fork seals started to leak very badly. I noticed some oily grime behind the front wheel on the silver plastic. After a good cleaning it reappeared quickly. A closer inspection showed one tube of the fork was slippery with oil.
That should not happen after just 20.000 km, but hey some of the roads I went were very bad and having the Sahara as a neighbor has its drawbacks.
The fine dust is our permanent companion but some days are bad. If you live in the USA you will get this stuff in Florida if the weather is right.
On the bright side, if we have dust in the Summer it mostly weaken the hurricanes you get.
To get a replacement fork oil seal I had to measure the diameter of the inner tube and of the inside of the outer tube since I could not find the measurements anywhere. A not sharp knife helped me to remove the dust seal.
Sorry, my main language is not English so with technical terms I have my problems.
Normally I would just go to a dealer and get a replacement kit (see parts catalog below) , but that would take weeks or months here, so I always have to improvise ...
Then I took off the front wheel, removed the "tupperware" and 4 screws later the 2 shocks came out.
To take the shock apart there is a hexagon head screw inside the shaft where the wheel bolt goes through. The fun part was when the allen wrench rotated the screw but the screw did not unscrew even it both shafts where secured. So I cut off the long part of the allen wrench, stuck it into a nut, and got my impact wrench. Funny, the impact wrench did not hammer but just rotated fast and the screw came out.
The thin shaft what sits in the steering fork. The thin rod with the tapered end is where the screw holds the 2 tubes together.
The big ring keeps the copper ring from slipping of the bottom and the thin washer on top keeps the copper ring from destroying the seal. The copper ring is all where the two tubes slide on each other. Pretty small area, isn´t it? So the next time you see some one riding just on his front wheel you get an idea about the stress what he puts on his fork.
Letting the big tube drain all the oil. There was some grime and fine metal shavings on the bottom what got cleaned by a paper towel on a stick.
Draining the thin tube. You will notice the knife I took from the kitchen on the top of the picture. You need that to pry the dust seal loose.
The new seal
Compared with the original seal the new one is better since it has 2 metal springs instead of just one.
I took the small tube apart to see why the screw would not grip properly. To do that I needed to remove the top cap.
As you can see from the first picture, there is a fancy wrench necessary to open the cap. I just put the tube back in the holder and used the pliers you see above to unscrew the cap.
There is nothing what secures the thin rod with the tapered end against rotating. So I guess when the screw gets stuck a drill or an impact wrench is the answer. By the way the screw from the first shock came out without a problem.
To get every thing back together is simple, just the copper ring needs some help with a couple screwdrivers and some soft tapping with a hammer around to sink it in the shaft.
After I finished it the new seal did not wanted to go into the shaft no matter how hard I tried. Taking the shock apart again to remove the new seal what got stuck took some screwing the upper tube back into the bike and then with force repeatedly jerking the lower tube towards the ground.
My dealer had given me the wrong seal. It was wrong by just 1 mm outside but that is all it takes not to fit.
So I cleaned the defective seal and reinstalled it. That was 3000 km ago and it is working nearly perfect. There is a very light film of oil on the thin shaft after a few days but it does not go any further.
Here is a trick, the metal spring inside the seal gets a bit loose over time. just unscrew (twist) it, cut off 5 mm and screw it back together and it will last a while longer.
The same you can do if you have problems when the sprag clutch starts to make noise.
The oil was very black and left some grime and metal shavings, so it got replaced.
Cover and front wheel removed.
The hexagon screw has normally a copper washer to seal against leaking oil. Smart as I am I lost a washer and naturally it is a special size what no one had. So I substituted with a hot water washer what i widened a bit inside to make it fit. Needless to say it works perfect.
This is the size you need: 41 mm 53 mm 10 mm
But you can substitute with 41 mm 53 mm and 0.5 mm more or less hight.
And here are the Bikes what can help you out:
650 Pegaso -94 41x53x8/10,5
CR 250 R 81 41x53x8/10,5
XR 250 R 86-98 41x53x8/9,5
XR 350 R 83-84 41x53x8/10,5
CR 450 R 81 41x53x8/10,5
FJS 600 Silverwing 01-05 41x53x8/10,5
VT 750 C Shadow (RC44) 97-00 41x53x8/10,5
VT 750 C Shadow (RC50) ab 04 41x53x8/10,5
VT 750 C2 Shadow ACE (RC44) 97-02 41x53x8/10,5
KX 125 (G1,H1-2) 89-90 41x53x8/9,5
KR 250, KR1, KR 1 S 89-93 41x53x8/10,5
KX 250 89-90 41x53x8/9,5
EN 500 (C1-8) 96-03 41x53x8/10,5
KLE 500 (LE500A) ab 91 41x53x8/9,5
ZX 6 RR (ZX600K/M) 03-04 41x53x8/10,5
ER 6 N/F (EX650A) ab 05 41x53x8/10,5
KLR 650 (KL650C) 95-01 41x53x8/9,5
Z 750 (ZR750J) 04-06 41x53x8/10,5
ZR 750 Zephyr (ZR750C,D) ab 91 41x53x8/9,5
ZR 7 / ZR 7 S (ZR750F/H) 99-04 41x53x8/10,5
ZXR 750 ,R (ZX750L,K,M) 93-95 41x53x8/9,5
GPZ 900 R (ZX900A7-10) 90-94 41x53x8/10,5
ZX 9 R (ZX900B) 94-97 41x53x8/9,5
GTR 1000 (ZGT00A1-11) Kardan 86-96 41x53x8/10,5
ZX 10 (ZXT00B) 88-90 41x53x8/9,5
GPZ 1100 Horizont (ZXT10E,F) ab 95 41x53x8/10,5
Z 1300 (KZT30A,ZGT30A) 79-89 41x53x8/9,5
M 125 89-90 41x53x8/9,5
AN 250 Burgmann (AN) ab 98 41x53x8/10,5
RM 250, RMX 250 89-90 41x53x8/9,5
AN 400 Burgmann (AU) ab 98 41x53x8/10,5
GSF 400 Bandit (GK75B) 91-94 41x53x8/9,5
GSF 600 Bandit (GN77B) 95-98 41x53x8/9,5
GSF 600 Bandit (A8) 99-04 41x53x8/10,5
AN 650 Burgman (BU) ab 02 41x53x8/10,5
DR 650 R,RE (SP41,44,45B) 90-95 41x53x8/9,5
DR 650 RS,RSE (SP42,43B) 90-96 41x53x8/9,5
GSF 650 Bandit ab 05 41x53x8/10,5
SV 650 N/S (AV) 99-02 41x53x8/10,5
DR 750 S (SR41B) 88-89 41x53x10,5
GSX-R 750 (GR75A) 85-87 41x53x8/9,5
DR 800 S, BIG (SR42B) 90 41x53x10,5
VZ 800 Marauder (AF) 97-04 41x53x8/9,5
VZ 800 C Intruder ab 05 41x53x8/10,5
GSX 1100 R (GU74C,D) 86-88 41x53x8/9,5
GSX 1100 RW (GU75C) 93-94 41x53x8/9,5
DT 125 R (4BL,3RM) 91-96 41x53x8/9,5
YZ 125, YZ 250 88-90 41x53x8/9,5
WR 200 R 93-94 41x53x8/10,5
TZR 250 93-95 41x53x8/10,5
WR 250 90 41x53x8/9,5
YZ 250 88-90 41x53x8/9,5
FZR 600 R (4JH,4MH) 94-95 41x53x8/9,5
FZS 600 S, Fazer (RJ02) 98-03 41x53x8/10,5
XJ 600 N,S Diversion (4KA,4MB,RJ01) ab 98 41x53x8/10,5
XT 600 E (3TB,3UW,4ME,4SK,4PT) 90-94 41x53x8/9,5
XT 600 84-93 41x53x10,5
YZF 600 R Thundercat (4TV,4WD) 96-99 41x53x8/9,5
YZF 600 R Thundercat ab 00 41x53x8/10,5
XVS 650 Dragstar (4VR,4XR) ab 97 41x53x8/9,5
XVS 650 A Drag Star Classic (VM022/25) ab 98 41x53x8/10,5
SZR 660 (4SU) 95-99 41x53x8/9,5
FZR 750 R (3CU,2TT) 87-88 41x53x8/9,5
YZF 750 R, SP (4HN,4HT) ab 93 41x53x8/9,5
TDM 850 (3VD,4CM,3CM) 91-95 41x53x8/9,5
TRX 850 (4UN) ab 96 41x53x8/9,5
XJ 900 S Diversion (4KM) ab 95 41x53x8/9,5
FZR 1000 Genesis (2LA) 87-88 41x53x8/9,5
FZR 1000 Exup (3LE) USD 91-95 41x53x8/9,5
YZF R1 (4XV,5JJ,RN01,RN04) 98-01 41x53x8/10,5
FJ 1100 (47E) 84-85 41x53x8/9,5
XVS 1100 Dragstar (5EL,5KSB,VP05) ab 99 41x53x8/10,5
FJ 1200 (1XJ,3CW,3YA) alle 41x53x8/9,5
this is the original Malaguti fork seal replacement kit. It did cost me 58 Euro and includes 2 dust seals, 2 oil seals (original quality with only one metal spring) and 2 clips to lock the oil seal in place.
Since my cleaned, former leaking, oil seal is still only leaking minimal I will postpone the replacement until it is really necessary.