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Fork seals leaking after one ride?

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I have a 2008 RMZ 250, I just had my forks rebuilt (including bearings, seals and bushings). After one ride about 20 mins. they are leaking!! Last year I had the forks revalved and the same problem last year. I went thru 4 sets of seals. It doesn't matter if I wash the bike or don't wash the bike they still leak. I do not use a pressure washer just normal garden hose. I used after market and stock OEM parts it still leaks with both. Does anyone have any suggestions?

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You might want to check the forks for deep scratches or some kind of gouge or nick in the tubes , as that would definately tear up a seal , when the forks were done , were they COMPLETELY cleaned and flushed so there was no possability of metal or debris that could still have been in there ?

unless you are somehow getting the wrong seals(i bought some All Balls and they were labled wrong and leaked the first time out)

but you said you tried OEM seals so they should have givin you the correct ones , so that leads back to the tubes having a scratch in them both (you did say both leaked correct ? ) that would rub on the seal wearing it out and causing the leak .

I would say you have a deep scratch or sharp edge on both forks and its sticking out enough to tear the seal , rub your hand on the complete tube , if you feel ANYTHING , it will be enough to cause a leak , you might get away with sanding it with wet/dry paper and getting the burr off , i believe there is a post somewhere on this site about filling a gouge in with something you can buy in a hardware or auto parts store and fixing the problem

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Are there any scratches on the inner tubes? Who changed your seals?

some exampels

-bad seals

-no grease (KYB or RT or....)

-scratches on the inner tubes

-not enough care when assemling seals

-tubes bent

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I have gone to two different shops with the same result. i have checked the tubes and did not find anything but i will check them again.

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I just checked the tubes no scratches that i can find. prior to revalving i went a whole year with no leaks.

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Have you cleaned the wipers? The part that fits in the upper tube on top of the actual seal. Just a thought.

It's pretty easy to damage a seal if extra care isn't taken when installing. I think I would certainly mention this to the tech that rebuilt your forks. They shouldn't be leaking after a rebuild unless something was wrong on installation.

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Maybe a seal bullet was not used? If no scratches were found and you only

have 20 minutes on fresh rebuilt forks, that tells me its an install

problem. Make sure your forks are not in a bind, may not cause a leak but

you never know. Cover all your basis before going back to the tuner/builder with a complaint. They should cover you on that and do a re-install.

By the way, your time stamp on your post only shows 8 minutes between your last post. Not trying to pick at you, did you drop your dust seals down and take a good hard look?

jwaseman

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maybe i don't understand but why would i drop the dust seal to look for scratches in the tubes? the shop i took the bike too put the forks back on the bike so you would think that they have the forks on correctly?

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Many years ago I had the same problem with a KX250. It leaked on the first ride when new. I had the seals and bushings replaced four times. They kept doing the same thing. Then I sent the forks to Pro Circuit, the replaced everything, did a revalve with springs. I got two rides out of that before they leaked. I had them replaced again by the Kawasaki shop. They leaked again and I traded it in on a Honda with the fork seals leaking. I lost my but on this new bike but the forks on the Honda never leaked. Now I use Seal Savers. I'm not sure if they are the reason my forks never leak but I am happy!

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Just so we are thorough that is all.

I did a rebuild for a guy and he had a bad leak when he brought the forks

to me. I pulled the dust seals down and the springs on the oils seal had

been jacked up somehow on install. Maybe using the wrong or homegrown

fork seal drivers. So if you pull your dust seal down, take a light and look

in there, make sure there is nothing that stands out. Take your time doing

it.

Yes, you would think that the shop installed the forks correctly. But you

never know!

Then again, You as the consumer should not have to troubleshoot

the problem, just take your forks back to the guy until they get it

correct. They shouldn't charge you any extra.

Edited by jwaseman

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i just talked to the shop, they said bring it in and they will fix it. i don't think that they did anything wrong, i'm just trying to figure out why it would be leaking already. thanks for all the good info.

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Did you bring in the whole bike, or just the forks? If you just brought in the forks, did you reinstall the forks and tire?

You say the problem has occured with various venders. How are you intalling your front wheel? If the forks aren't parallel, the seals will leak.

I had a similar issue years ago. I was improperly installing the front wheel and the fork tubes weren't parallel. This caused wear to the seals and they began leaking.

Try this;

1. With the bike on a stand and the front wheel off the ground,

2. Install the axle through the forks and tighten the brake side pinch bolts only.

3. Spin the wheel forward, then stop the wheel with the front brake. Repeat 3-4 times. Repeat this again, 3-4 times, spinning the wheel in the opposite direction.

4. Tighten right side pinch bolts.

This method uses centrifigal force to align the fork tubes.

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Do you trailer the bike anywhere? I have seen guys strap their bikes down tight almost until the front wheel is hitting the fender. I don't think thats good for any suspension and it may cause a blowout. I've also heard that if the compression is set too hard that it can also contribute to seal failure. Now I'd assume if you had your suspension set up that wouldn't' be an issue.

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Did you bring in the whole bike, or just the forks? If you just brought in the forks, did you reinstall the forks and tire?

You say the problem has occured with various venders. How are you intalling your front wheel? If the forks aren't parallel, the seals will leak.

I had a similar issue years ago. I was improperly installing the front wheel and the fork tubes weren't parallel. This caused wear to the seals and they began leaking.

Try this;

1. With the bike on a stand and the front wheel off the ground,

2. Install the axle through the forks and tighten the brake side pinch bolts only.

3. Spin the wheel forward, then stop the wheel with the front brake. Repeat 3-4 times. Repeat this again, 3-4 times, spinning the wheel in the opposite direction.

4. Tighten right side pinch bolts.

This method uses centrifigal force to align the fork tubes.

The only problem with this method tho is you are just "assuming" that its right. If you do it my way you will actually "see" that its right.....

1.Install both forks and set fork height using calipers or a ruler. It is important that fork height be exactly the same for both sides. Tighten pinch bolts to the proper specs (Top: 18 Ft-Lbs | Lower: 15 Ft-Lbs).

2.Before installing axle make sure the end of it (and the edge of axle hole) has not been "mushroomed" from hitting it with a metal hammer. If theres any lip it must be ground off or fork will bind.

3.Install the axle (use rubber or plastic hammer only) and tighten the axle nut to proper spec (75 Ft-Lbs). If the axle turns while tightening, tighten one right side axle pinch bolt to hold axle in place.

4.Tighten both left side axle pinch bolts to spec (17 Ft-Lbs).

5.With the left side axle pinch bolts and axle nut tightened, loosen the right side axle pinch bolts. Take a small flat head screwdriver and carefully tap it into the slot between the two right side axle pinch bolts. This will enlarge the axle hole. You will then be able to grab the bottom of the right side fork tube and push it in and pull it out freely. You will be able to see the fork settle naturally into position on the axle without binding.

6.Remove the screwdriver and tighten the right side axle pinch bolts to spec (17 Ft-Lbs).

If you're wondering if your forks are currently bound up, put your bike on a stand and start this procedure at Step 4.

doc

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i did take the bike in they installed the forks and wheel. when i trailer the bike i use a fork support. i think that i'm doing the front wheel install correct because i have had about 6 to 8 sets of tires on the bike and i do them myself with no problems.

i have 2 rides on the bike since i took it back to the shop and so far no leaking..

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The only problem with this method tho is you are just "assuming" that its right. If you do it my way you will actually "see" that its right.....

1.Install both forks and set fork height using calipers or a ruler. It is important that fork height be exactly the same for both sides. Tighten pinch bolts to the proper specs (Top: 18 Ft-Lbs | Lower: 15 Ft-Lbs).

2.Before installing axle make sure the end of it (and the edge of axle hole) has not been "mushroomed" from hitting it with a metal hammer. If theres any lip it must be ground off or fork will bind.

3.Install the axle (use rubber or plastic hammer only) and tighten the axle nut to proper spec (75 Ft-Lbs). If the axle turns while tightening, tighten one right side axle pinch bolt to hold axle in place.

4.Tighten both left side axle pinch bolts to spec (17 Ft-Lbs).

5.With the left side axle pinch bolts and axle nut tightened, loosen the right side axle pinch bolts. Take a small flat head screwdriver and carefully tap it into the slot between the two right side axle pinch bolts. This will enlarge the axle hole. You will then be able to grab the bottom of the right side fork tube and push it in and pull it out freely. You will be able to see the fork settle naturally into position on the axle without binding.

6.Remove the screwdriver and tighten the right side axle pinch bolts to spec (17 Ft-Lbs).

If you're wondering if your forks are currently bound up, put your bike on a stand and start this procedure at Step 4.

doc

So after I do your method Doc, How can I tell thats its right? Is it a visual or a mechanical confimation?

Bill

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Choose the method you want, it's your bike.

http://mx-tech.com/downloads/FORK_INSTALLATION.pdf

This is from the MX TECH website;

FORK INSTALLATION

The correct installation of the front forks is essential to proper suspension operation.

1. Put bike on a stand that will enable front tire to be off the ground.

2. Install forks in triple clamps, Ensure that both forks are the same height in the triple clamps, (refer to your owners manual for the correct dimension). Also, make sure that the bleed screws are towards the front, this will make bleeding the air from your forks easier.

3. Tighten each bolt (in an alternating fashion) in the top clamps to 220 inlbs.

4. Tighten the lower clamp pinch bolts to 168 inlbs. (Over tightening of the lower pinch bolts may result in a mid-stroke harshness condition).

5. Install front wheel assembly sometimes it helps to pry the brake pads apart a little with a screw driver before bringing the wheel into position).

6. BEFORE tightening any pinch bolts go ahead and fully tighten the axel nut. (If you cannot hold the axel to tighten the nut, go ahead and tighten the right side pinch bolts just to hold the axel while you tighten the nut. MAKE sure you loosen the right side axel nut pinch bolts before you proceed any further).

7. Spin the front wheel and abruptly apply front brake, repeat this a few times.

8. Let off of the front brake and tighten the left side (caliper side) pinch bolts to manufacturer recommended torque rating.

9. Again, spin the front wheel and abruptly apply front brake, repeat a few times.

10. Tighten right side pinch bolt to recommended torque value. This procedure will ensure that the front forks are parallel and that no binding will occur.

Ride and Enjoy!!

Edited by snb73

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Choose the mothod you want, it's your bike.

http://mx-tech.com/downloads/FORK_INSTALLATION.pdf

This is from the MX TECH website;

FORK INSTALLATION

The correct installation of the front forks is essential to proper suspension operation.

5. Install front wheel assembly sometimes it helps to pry the brake pads apart a little with a screw driver before bringing the wheel into position).

Ride and Enjoy!!

The only thing I would do differently in #5 would be to pop the master cylinder cap off before trying to pry the brake pads apart.

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