Fork seals leaking @19,000 miles on ODO

[flynrider]

After using the Sealmate successfully on both CBs, I often wondered how difficult it would be to make my own, when needed. It's just a thin piece of plastic with a hook shape. I always thought a properly cut plastic playing card should do the trick.

Last week I got a chance to test my idea. On the way to Utah for a meeting with Frulk and Django, I noticed that the right fork seal on the CB750 had developed a substantial leak. Bad enough that I could see a large drop of fork oil form behind the tube every 10-15 min.

At one of my gas stops I was able to buy a pack of cards and a pair of scissors. When I arrived at my destination, I cut a card into the general shape of the Sealmate and gave it a try. That's when I found out that not all playing cards are plastic. These turned out to be plastic coated paper and started to come apart after a half turn around the seal. Not to be deterred, I just cut out several of them and cleaned out the seal a section at a time.

Overall, this experiment in roadside engineering was a great success. The fork was sealed up tight and hasn't dripped for 1,500 miles.

 

[GoldOxide_imp]

" ... That don't bother me at all
Playin' solitaire till dawn with a deck of fifty-one ... "

 

[Bazbro_imp]

Great 'How To", Flyn! Full marks to you.

GO... :rofl:

 

[flynrider]

" ... That don't bother me at all
Playin' solitaire till dawn with a deck of fifty-one ... "

I cut up the Joker and the instruction card for poker. So, at least in theory, I'm still playing with a full deck.

 

[Bazbro_imp]

I stopped "playin' with a full deck" years and years ago...! :rofl:

 

[Rocky_imp]

Nicely done Flynrider

 

[Ben70_imp]

Great tip Flyn! I nominate the clear plastic packaging that many items from Costco are encased in. Haven't tried it but I am going to save any flat pieces I come across for future reference. Thanks for the tip.

Ben

 

[max]

Have not tried the seal mate but when you use it do you remove the top dust seal and have better access, can see what you are doing or just work it round and hope the edge has collected the dirt and has resumed sealing again?

 

[pekingduck]

Have not tried the seal mate but when you use it do you remove the top dust seal and have better access, can see what you are doing or just work it round and hope the edge has collected the dirt and has resumed sealing again?

Yes, definitely pull the dust seal up. You can't access the actual seal lip unless you do. You will probably find a puddle of dirty oil that you want to clean out first.

When you're done, wipe some WD40 or silicone spray on the fork tubes occasionally. That may help keep dried on mud or dead bugs from causing the problem again.

 

[flynrider]

Yep. In the photo above, the thin screwdriver blade of the multi-tool was used to gently pry the dust seal free and slide it up the tube.

It's also a good idea to run the tool between the fork tube and the dust seal. That'll keep any trapped dirt from migrating down to the actual fork seal.

Pekingduck also makes a good point about cleaning out the area above the fork seal before you start. I used a microfiber cloth wrapped around the point of the screwdriver blade and ran it around the top of the seal. This gets rid of any potential contaminants that have already made it past the dust seal.

Great tip Flyn! I nominate the clear plastic packaging that many items from Costco are encased in. Haven't tried it but I am going to save any flat pieces I come across for future reference. Thanks for the tip.

Ben

If you're referring to the clear plastic clamshell type material, I think that might be a bit thick and rigid for this application. The tool has to be thin enough to bend easily and conform to the round shape of the tube as you slide it around the seal.

If you do decide to try it, make sure the edges are super smooth. The last thing you want to do is cut or tear the soft rubber seal.

 

[max]

Thanks for the advice and the hot tip about the clear packaging, i have no problem with any of my seals at the moment but i want to learn about things when the knowledge is available, very difficult to beat first hand experience

 

[SportsterDoc]

Only replaced fork seals on one of my bikes, but I did clean the bugs off frequently.

 

[Bazbro_imp]

This is an obvious area for "prevention is better than cure". A wash down and polish/lubricate after long rides would seem to pay dividends in fork seal life.

 

[pdedse]

Reviving this thread...

Was ready to head out for Christmas Eve day ride, but noticed a few drops of oil on the floor below the left side fork seal. Ruh-ro.

Well, times like these is what I bought the W800 for, so it got the legs stretched instead of the CB1100. After a wonderful 40 degree ride tarnished slightly by a much colder than that drizzle the last 5 miles of 50, I started thinking about the fork seals. I remembered and found this thread, and knew that I had bought the tool, but not the motion pro one, but rather the Rhino Seal Doctor one.

I think it was about $20 5 years ago. I think I bought it instead of the motion pro because it was sturdier...IDK, or maybe because it was red.

I actually bought it for my KLR650 at the time because it had leaky seals. It worked once, but a year later started leaking bad...new seals solved the issue then.

So I'm hopeful the seal doctor device works for the CB leak.

After wiping down the fork and cleaning it, carefully pried up the dust seal


Inserted the hooked end and circled the fork seal 2x


And this is what came out


Yum! Although...does that look like "meant to be there" grease type material to keep the fork oil in?

Or just build-up that was causing the leak?


The other end of the tool is for cleaning the inside of the dust cap


Compressed the forks several times, a bit of residual oil, and did that a few times till all dry


Video of clean check:

[url=https://i.imgur.com/pBhBLP1.mp4]https://i.imgur.com/pBhBLP1.mp4

Did the same for the other fork and the same built-up pasty material was removed. Forks are bone dry. Now I need to test ride to confirm.

 

[peterbaron]

 

[GoldOxide_imp]

Coolio pdedse.

 

[Cormanus]

Good work, pdedse.

 

[The Gecko_imp]

Hi pdedse, the strange "grey matter" you found is simple sludge - not a grease meant to be there. At least color, origin and amount, together mileage and location points this way. Sludge is created by squeezing oil and water through small spaces, over and over and over again. And unfortunately it does neither preserve the desirably properties of either water or oil. Very good that you got it out. It means probably that some water got past the outer seal.

 

[max]

Fntastic work Pdedse, done the same on my upside down forks on the cb1000r, caked-on stuff on the inside of the forks
worked its way in between the seal lips, the front fender has some protecting shields build in and they do a fine job but it still needs some attention from the owner for best results.

First thoughts were to replace the seal, thought about it and decided that a seal does not wear out at 20.000 km!
Did the same thing as you did with perfect result, i could feel something at the back of the fork leg so cleaned both with autosol and maintain a regular cleaning routine, some insects leave a sticky resin like liquid behind which in the wrong place can pose a problem, thanks for the very nice clear pictures!

 

[GoldOxide_imp]

Explains why some modern street bikes have adopted the clunky plastic stanchion protection mechanism from offroad and adventure bikes.