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KLX300R fork seals

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I had a good weekend going, soaking up suds :thumbsup:, put new TAG bars on, changed the oil and filter, then I noticed a ring of oil about ¾ of the way down on the forks. After compressing the forks it leaves an oil film and a ring at the bottom of the compression. I would assume I’m looking at a blown seal, but you know what that means when you assume :devil:. It usual means I'm going to pay a mechanic for something I suggested :awww:. I have no experience with a fork seals. What do you folks think, how much am I in for, and can I ride for a while with it the way it is? The bike is 4 months old with 150 miles on it. I haven’t jumped anything big, but I’m around 200lbs, which is supposed to be heavy for the stock springs. Thanks in advance for you input.

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The fork tubes can get dinged. Usually laying it over in rocks and sliding backwards down a hill does the trick. Just a little ding can create a sharp edge and cut the seal enough to make it leak. No big deal, just find the ding and slowly/carefully sand it smooth with 400 grit sandpaper. Then of course you have to put in a new seal.

Installing a new seal is not that difficult, but forks usually do require a special tool. There is a socket way down inside that you have to hold, so that requires a tool. I usually make my own by welding a nut to a piece of tubing.

I am not sure what is meant by a blown seal. Can anyone explain? If you totally bottom out hard, what does this do to the seal? I guess if you had the forks too full of oil and bottomed out, it might push the seal out from where it is supposed to be, but it shouldnt ruin the seal. I have heard the term blown seal many times but I don't quite know what it means. Every time my seals have leaked, I had a ding or the bike was old and they just wore out from scraping dirt off the chrome 10 billion times.

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The other thing to check is that you may have some grit in the dust cap. Take a negative (photo negative) or a thin feeler guage and run it up around the fork tube up inside the dust seal. It's amazing that this will do the trick most of the time - clearing out some crud that is keeping the seal from sealing completely. Lolley is right about the ding in the fork tube though. If you can't see a nick in it, I'd be willing to bet you just have some crud up under the seal. With only 150 miles on your KLX, I highly doubt your fork seals are "gone". (4000+ miles and I've only changed them when I had my suspension done at around 2500 miles)

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After compressing the forks it leaves an oil film and a ring at the bottom of the compression. I would assume I’m looking at a blown seal, but you know what that means when you assume

I think he means worn enough to leave the tell tale oil ring at the bottom of the fork leg. the bike sounds too new to have rock and ding damage. It's not uncommon for the seals to dry out after being in storage for a while, or in transit. There is an old trick I used to stall seal replacement. In your case, it will buy you time to check the web for how to's for seals.

Remove the forks and place them upside down after your remove the dust seal with a thin blade screw driver. You are now looking at the wire retaining ring and the seal. Clean it well and slip a piece of plastic 35mm film between the shaft and seal to remove any dirt causing the leak. Clean it again and fill the hub with some brake fluid. It will actually cause the seal to soften and rejuvenate, getting a better seal. Slimy bike dealers did it on new bikes to get out of the warranty period and guarantee a seal job several months later.

You will need a torque wrench to torque the triple clamp bolts no more than 14 lbs. You also need to pump the forks before tightening the 4 - 10mm pinch bolts on the axle clamp. This helps line up the forks.

It might buy you some time on a new bike.

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Thanks for tips. I'm glad you guys are hanging around TT on a holiday, like myself. I'll try the film negative this afternoon. I'm keeping my fingers crossed. The "blown seal" term is something I read in other post.

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I am not sure what is meant by a blown seal. Can anyone explain? If you totally bottom out hard, what does this do to the seal? I guess if you had the forks too full of oil and bottomed out, it might push the seal out from where it is supposed to be, but it shouldnt ruin the seal. I have heard the term blown seal many times but I don't quite know what it means. Every time my seals have leaked, I had a ding or the bike was old and they just wore out from scraping dirt off the chrome 10 billion times.

I'm pretty sure that the term "blown seal" comes from when your bike is tied down in the back of your truck or on your trailer. If the straps are too tight, they put a lot of prusser on the oil and the seals, and after sitting for a while, the seals bust due to the pressure. I'm pretty sure that's it, but not posotive.

Kevin

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Some good news and bad news. The good news is it looks like using the photo negative has stopped most if not all of the leaking. The bad news is there is a nick in the forks. The nick is right in the center of the fork guards. I don't know how I got it or if came off the line like that. I think my time is limited on that seal. Thanks again for the help. :thumbsup:

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I bought my 2001 klx 300 a few months back and the first thing I needed to do was to change the seeping fork seals.

First off, you don’t need a "special tool" to just change the KLX’s oil and/or dust seals other than the seal driver and oil level gage I describe below. The tool that I think someone referred to is used to hold the inner 'tube' in place if you are removing the valves at the bottom of the fork - using a hex socket on the valve turns the inner tube. If you upgrade the valve, you would need a special metal tool. You don't need to touch the valves when doing the seals.

First off, I suggest you order your fork seals from Rocky Mountain ATV. Chaparral has a crappy return policy, and I refuse to buy from them again. RM ATV was very customer friendly. Personally, I refuse to pay dealer prices.

I'll walk you through what I did. To begin, loosen, but don’t remove, the fork caps. I moved my handle bars out of the way and used a large socket after my wrench seemed to be damaging the alumimum caps. You don’t need to loosen or remove the little screws w/in the caps.

Remove the fork from the holder, set upright and loosen the cap, the outer-upper fork will drop down exposing the spring but the spring is retained in the assembly - it doesn’t shoot out. Dump the oil. Remove the caps from the inner assembly, and springs leaving the inner assembly in place.

Lower the dust seal. Remove the retaining clip below the oil seal. Now firmly pull the upper and lower shocks apart. It took me four or five tentative but firm yanks to separate them. On the upper part of the lower shock, you will see two bushings. Slide the two bushings up so you see how they fit together under pressure. FYI: This is what you are creating when you ‘drive’ the oil seal into place. Its good to understand how the bushings interact.

Using a flat head screwdriver, open the flat bushing just enough to pull off the top. Slide the other bushing and oil and dust seal off. Open your new seals and cover the top of the fork with the plastic bag the new seal came in (or any thick plastic) because the top of the lower fork has places that are sharp and that can damage the new seals and cause them to leak if you are not careful. Gently run your finger down the tube, top to bottom, you will know what I mean. Now rub the plastic with oil and slide your new dust seal and new oil seal on. Next slide the bushings on in reverse order in which they came off. Gently push the lower fork into the upper and you need a way to balance the assembly upside-down. Since the spring is out, the upper tube just wants to freely collapse and / or fall off the lower tube. I suspended my shock with a tie down hooked through the axle hole hooked to my garage door support assembly above. The upper fork (larger tube)was supported by a makeshift work table (two saw horses & old door). This stood the shock upside down. (You may want a rag underneath to catch residual oil dripping out). Remember, the upper fork is free to ‘fall’. You can adjust the height by taking up slack in the tie down (pulling the lower fork higher). You want the upper fork (now touching the work table) to be supported by the table so that you can put pressure on the upper fork body without it falling off the table.

For a seal driver, buy a 2 in thick PVC plastic pipe (you will need about 6 or 7 inches of length) and cut down the middle (offset from exact middle so 70% of the original is in tact versus a 50/50% cut). Take the larger of the two PVC pieces and remove any sharp edges on the end that is going to touch your oil seal, and place it into two c-clamps overnight so that it temporarily approximates the outer diameter of the inner (lower) fork tube. It is properly formed when it fits between the inner and outer fork tubes so you can drive the oil seal into place. You are using the smooth end of the plastic to ‘ram’ the oil seal and push the bushings into place (which are behind the oil seal).

Once the diameter of the PVC is correct, by hand, push the oil seal into place and push the PVC around the lower (smaller) fork tube and ram the oil seal into place. You will need to turn the driver after a few impacts so that the impacts are all around the seal, rather than attempting to drive the seal by hitting it only in one place. The seal needs to seat far enough to put the retaining clip back into its grove. Once its in, your almost done.

Next, the oil measurement is done from the top of the fork, fully compressed without the spring installed. Support the fork right side up, and so its’s level and won’t fall. I stuck mine in the corner of my 4x8 utility trailer and strapped it into place.

To measure the oil, I used a turkey basting syringe that had a flat surface at the bottom so that it would sit on the outside of the upper fork (for correct oil level measurement). I stuck a drinking straw on the end of the syringe (in place of the needle) and cut the straw to the desired length, which I think was 100mm. Check your specs to make sure. The length from what will be the top of the fork (bottom of the syringe) to the end of the straw, is your oil level measurement. Pour in oil by eye, and suck out excess w/ the syringe and straw assembly. Repeat this with your other shock, and your oil levels are exactly the same.

Replace the spring over the guide and re-assemble. I had to use a needle nose-vice grip pliers (wrapped with duct tape) to hold the inner guide while I manually compressed the spring. Now that there is oil in it, it can be tricky to not dump the fork over. It took a few tries.

Since you are 200 lbs, which I am too, I would suggest a higher weight (thicker) oil. I went with 7wt oil. I also have a .42 progressive front spring which is beefier than stock. I can't seem to bottom it anymore. I'm conservative though, I am rarely over 4ft off the ground. I haven't tried the set up on rough trails at speed though.

A good cheap upgrade would be the heavier springs (under $100). RM ATV has them. A good time to upgrade is while you are replacing your oil seals since the springs will be out anyway.

Maybe the guys in this post can tell you if a 15w oil with the stock springs and restricted valve setting may also do the trick. Get your oil from RM ATV also. My dealer wanted $9 per quart. You need two quarts by the way.

It took me 3 hours for the first shock and 30-40 min for the second. Most of my first shock time was figuring out that I DID NOT need the special tool to replace just the seals.

This should be enough into, in conjunction with your repair manual, to get the job done. It saved me a few hundred bucks in taking it to someone else.

Good luck. :thumbsup:

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Thanx for the instructions. :thumbsup: I think I'm going to give it shot soon. I'll do the springs at the same time. I know what you mean about paying dealer prices. He's gotten enough of my money this year, and I never feel good about spending my money there.

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Since your bike is fairly new, pull down the dust seals and check check them for cracks etc. If you can, reuse them. Mine were warn or cracked in places. If you do re-use them, just pull them down out of the way and just leave them on the lower fork (would save another $20 or so) and remove only the two bushings and the oil seals when doing the replacement.

Also, take a look at the valve upgrade procedure entitled "Race Tech Gold Valve Install" under "Hop Ups" in the PlanetKLX web site. It shows you pictures of the forks in various stages of disassembly. I'm visual, so this was an immense help. It also has other applicable info.

Just remember that the special metal "cartridge holding tool" is not needed in the seal replacement procedure since you are not removing the valve. It took me a while to figure out this tidbit of important info - it would have saved me a lot of time.

You may want to post a question regarding the proper oil weight. I guessed with 7w. You may want to go with a thicker oil if you are an agressive rider. Also, consider turning down your compression clickers to more restrictive setting so the rate of compression is slower. There is no rebound adjustment.

I'm glad I did my own work and thus far, no more oil leaks from my seals!

FYI, if you don't have a service manual - get one. And post lots of questions on this site. The guys here are invaluable and will save you the headache of stupid mistakes. Trust me, I've made them!

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I've played around with the clickers and I've noticed that if I turn them in even a click or two the front tire pushes out of the turns. It seems to go from really soft to really hard. Anybody else notice this?

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I noticed a big difference with just one click this last weekend at the mx track. Not woods riding, but the front seemed to handle the whoops and jumps a lot better. I didin't notice it pushing out of turns though. I'm not sure what two clicks in would do, maybe it would start to push out of corners. I want to get the bike out in the woods before I mess too much with the valve settings.

Oh, one point of clarification about the disassembly. I looked at the service manual last night to refresh my memory. There is a washer between the bushings and the oil seal. So it goes - two bushings, the washer, the oil seal and the dust seal.

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I've played around with the clickers and I've noticed that if I turn them in even a click or two the front tire pushes out of the turns. It seems to go from really soft to really hard. Anybody else notice this?

Clickers huh....

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Follow this guide to changing your seals.

http://www.mxboards.com/forums/viewtopic.php?t=20

Installing a new seal is not that difficult, but forks usually do require a special tool. There is a socket way down inside that you have to hold, so that requires a tool. I usually make my own by welding a nut to a piece of tubing.

I do my seals every year and I have no idea what this mysterious nut your talking about is.

F2340.Gif

Which # here.

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