Fork Seals Leaking

Lew · Jan 18, 2003

Well There I was all proud. My nice freshly washed KTM all ready for its first Harescramle tomorrow. Then, What do I see....BOTH fork seals are leaking. Man I did not need this. I read through Mikeb's thread on his fork seals and I have downloaded the WP service manual, and was considering tackling this myself. Does anyone have a "home built" tool for seating the seal or do I need the specific tool. Also any specific brand of seal that will last a bit longer. I am definately putting on some seal savers since I will have it apart. Afterall This bike has 10.5 hours and 175 miles. Seems a little premature for the seals to give up so soon.
Thanks
Lew

mkuriawa · Jan 19, 2003

Lew,

Before changing them make sure they are clean, could be possible they just have some dirt in them causing the leak. In addition to putting the seal savers on take the spring off the dust seal and shorten it, it will create a tighter seal to help keep dirt out.

I had the same issues on my 99, it would go through seals every few months until I shortened the springs and installed fork booties - the last set of seals that I replaced were in the bike for 2 years and still going strong when I sold it.

I picked up my 03 200 SX a few weeks back and did not even consider riding it without the springs shortened and the booties installed. Some people do not think the seal savers (booties) work but I like them and so far for me they have proven to be a cheap fix. Don't forget you still have to get under the dust seals and clean every few rides - do not take the seals for granted!

Mike

JTT · Jan 19, 2003

Lou, before you get carried away and tear the forks down, try this simple fix:
-take a piece of 35mm camera film
-lift the dust seal and clean out all the debris
-take the film and slide it between the fork tube and the oil seal rotating in a scooping motion. It might take a few tries to get it.
Most times a fork seal leaks it is because of a small speck of dirt trapped between the seal and tube, as mkuriawa just mentioned. Rarely is the seal damaged, particularly one as new as you are talking about.

Look at it this way...it can do not harm and may save you some work before your event :think:

CR REV · Jan 19, 2003

When you do decide to tear down your forks there are homemade seal drivers. Take a PVC coupler and split it in two. Next grind/sand down the ridge on the inside. Now clamp the two halves around the fork leg with large hose clamps. Now use the entire leg like a slide hammer. I had a hard time finding a pVC set up for the 43mm on my old Husky but 46mm and 48mm are easy. I can't remember the size. I bought several couplers and even took the tubes into home depot to find something. My KTM shops claims that on most of the newer bikes the seals go in quite easy. This proved true on the 48mm WP's.

For more ideas on seal drivers do a search on homemade seal driver. That is where I got my ideas a couple of months back.

The film trick can buy you some time but eventuly you will need to breakthem down, clean, cahnge oil, etc.. I learned the hard way on some tempoaray fixes. Don't try electrical tape!! I was told to wrap tape around the fork leg and compress the forks to clean them out. I ended up with alot of oil on the ground and the tape stayed up in the fork tube!!

socal scott · Jan 20, 2003

The seal spring on the oil seal is to loss.
After you clean both dust and oil seals, remove the oil seal spring from the tube. Find where the ends join and unscrew. Now cut 4mm's off the small end then install.

Lew · Jan 21, 2003

Thanks for the tips. I used a film negative from some pictures and scooped out some grit, but the right fork continued to leak. I think it has stopped now because there is no more oil left. So, I think I will break them down and attempt to change myself. I have had KDX forks apart before and I have the wp service manual I downloaded. Anybody have a preference on oil height, and I assume I will measure the oil with the spring out and forks collapsed?
Lew

Fred T · Jan 22, 2003

135mm-140mm Lew. Bel Ray 5 wt. Spring out, forks collapsed. I just went through "fork training" class from my expert suspension guru last weekend. He showed me how to change the oil in them.

tightwoods · Jan 22, 2003

My '03 450 EXC, with only 75 miles, has a leaky left fork seal. Air has been bled from forks. This is inexcusable for any new bike, especially for one that costs this much. The factory fork seals are junk as far as I'm concerned. It's very rare for a Japanese bike to have this issue. Does anyone know of a better grade replacement?

tightwoods :(

Fred T · Jan 22, 2003

Originally posted by tightwoods
My '03 450 EXC, with only 75 miles, has a leaky left fork seal. Air has been bled from forks. This is inexcusable for any new bike, especially for one that costs this much. The factory fork seals are junk as far as I'm concerned. It's very rare for a Japanese bike to have this issue. Does anyone know of a better grade replacement?

tightwoods :(

This is where having a good dealer comes into play. Mine would have taken care of me no questions asked. I've ridden with a pack of KTM's on my past few rides and no one has any leaky seals. I think you're situation is some what unique. Did you clean them? Do you wash your bike after each ride? I'm clueless as to why you are having these problems. I've got just about 1000 miles on my '03 and she's just perfect. Sorry I can't be of help other than to suggest you cantact your dealer.

JTT · Jan 22, 2003

Originally posted by tightwoods
It's very rare for a Japanese bike to have this issue.

...there are many who would disagree :ugg:

marcusgunby · Jan 22, 2003

KTMs have fork seal problems-however so do jap bikes(especially YZs for some unnown reason)The KTMs do seem to be prone to this-they have gone to jap bushes in 03, maybe in 04 they should buy the seals as well?

socal scott · Jan 23, 2003

tight, as I said above...shorten the oil seal springs, they provide little tension in stock form. No teardown required, can't hurt to try it. My latest seals are living.

agitt73 · Jan 23, 2003

I BOUGHT THE K&S SEALS AND DUST SEALS ON EBAY FOR APPROX.
$26 SHIPPED AND LET ME TELL YA THEM DUST SEALS ARE ALOT
BETTER THEN STOCK FOR SNUG FIT BY THE WAY MY BIKE HAD ONE
SEAL START LEAKING ON MY SECOUND RIDE (RIGHT SIDE) BLEED THE
AIR AND IT WOULD STOP FOR ABOUT AN HOUR OF RIDING ANYTHING
LONGER THEN THAT IT WOUL START LEAKING AGAIN SO FAR NO LEAKS ON MY NEW SEALS IM RUNNING 110MM OIL LEVAL BEL-RAY
5 WEIGHT RACE TECH SAYS RUN 95MM MX TECH SAYS 120MM

^SQUID^ RACING · Jan 24, 2003

Leaky fork seals are a fairly common problem on alot of bike's. Last year, during the Malcom Smith ride @ Williams Lake, B.C., just about all of the new '03 KTM's had leaky fork seals. I had a '02 400 EXC, and my seals leaked on several occasions. Try removing your dust caps, clean the forks with a rag, and spray them with Slick 50. This seems to help.

Lew · Jan 24, 2003

Well it turns out that I am a big chicken. I have decided to take my fork legs to a shop and have them rebuilt. I found a tuner about 50 or so miles from my house (euro cycle). He seemed pretty knowledgeable on the phone, stated he will use a better quality dust wiper than stock. This is also where my nearest KTM dealer takes their suspensions for work.

Is anybody using "popper" valves to bleed the air from the forks. The idea seems positive to me as there are no tools involved to bleed, just push on the cap. This would be very quick and easy when out on the trail.
Thanks again for all the help/ advise
Lew

tightwoods · Jan 24, 2003

Yes, any bike can have a bad seal from the factory but that should be an exception, not a systemic problem as seems to be the case with KTMs in particular. My dealer has been a KTM only dealer for many years and he tells me that it is quite normal and common for any of the brand new KTMs (never ridden) to leak fork fluid on his showroom floor. Again, I maintain that this is inexcusable for any modern motorcycle, regardless of brand. 21st century seal technology is well developed. The only way a new fork seal could leak is if it's damaged during installation, poorly designed (seal lip spring tension, seal lip shape), or poorly manufactured (cheap tooling, inferior materials, poor quality control). Maybe the bean counters are to blame. In my 20 years as a mechanic in a Honda shop I don't recall leaky fork seal issues with any new bikes except for the occasional factory fluke.

tightwoods

mike rue · Jan 25, 2003

A bud of mine told to get seals for a 02 sx 250. a ktm rep. Told him that in 03 they changed the the seal and lessened the spring tension to remove some fo the stiction in the fork but now they are pron to leaking. Also shorten the spring on your on your dust cap and install seal savers. He has been through two oil changed with the same seals and no leaks.

btullberg · Oct 14, 2005

KTM Leaking Fork Seals

I've done the recommended "fixes" and I still have leaking fork seals. Who can recommend an aftermarket seal that won't leak, and what brand/weight fork oil? Also, where can I find the simple procedure to refill the forks to the proper level? Thanks.

cliwar · Oct 15, 2005

I have just installed a set of Synergy Seals (http://www.synergyseals.com/) on my '03 200 EXC. They were easy to fit without any special tools except a thin strip of plastic to guide them into the fork leg. So far I have only ridden for a couple of hours in a hare scramble since fitting the them, but they appear to be working well so far.

Yamadad · Oct 18, 2005

The tip about shortening the spring is the real deal and is a must. IMHO

My understanding is the WP seals are designed to have ultra low stiction and thus leak. Since KTM are essentially race oriented bikes, a single race is all they need to get out of the seals.

john hubbard · Nov 1, 2005

I had the same problem too on my 98 KTM 300 MXC. I replaced the seals, put on a pair of seal savers and presto, no leaks in 9 months! Rebuilt my Maico forks, added seal savers for insurance...again no leaks noted. Some people don't like them on the inverted forks, but they work well on the conventional forks -- at least in my case. Checkout KTMtalk's suspension section and you'll find all the answers you need.

John

Fork Seals Leaking

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