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Discussion Starter · #1 ·
After I ride my left fork ends up with this black/brown sticky stuff on it. This bike is 7 years old and has lots of miles. I just serviced the fork myself last year with Enduro seals and Fox oil (it's a fox float 32 RL).

The stuff comes off pretty easy but I don't know what it is... Here's some pics (hard to take without getting a reflection)

View attachment 888316

View attachment 888317
 

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It's dirty oil/suspension fluid being left on your stanchions.
It holds on to dust and dirt from the trail.
Looks like oil is leaking past your seals.
If your change to Enduro seals was the first service and seal change the fork has had, it may have gone too long between service intervals.
Also, the pictures look like you have vertical wear marks from the leg bushings showing on the stanchion. The lower pic has a mark that looks like bushing wear.
Look just to the right of the reflection in the lower pic-darker vertical mark extending a few inches above the seal.
 

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Discussion Starter · #3 ·
It's dirty oil/suspension fluid being left on your stanchions.
It holds on to dust and dirt from the trail.
Looks like oil is leaking past your seals.
If your change to Enduro seals was the first service and seal change the fork has had, it may have gone too long between service intervals.
Also, the pictures look like you have vertical wear marks from the leg bushings showing on the stanchion. The lower pic has a mark that looks like bushing wear.
Look just to the right of the reflection in the lower pic-darker vertical mark extending a few inches above the seal.
Yeah the Enduro seals was the first. There are no wear marks it's just the way it shows up on the pic... That is the first thing I checked for.

Is it OK to keep riding?

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You can keep riding, but your fork is likely due/overdue for service.
FOX specifies 30hr ride time intervals for fluid changes.
Seal replacement can vary greatly, sometimes they need replaced in 30hrs, sometimes they last months/years.
That residue you are seeing is an indicator that fluid is leaking past the seals.
If it's dark and dirty looking, it's likely your suspension fluid is dirty as well.
If you ride a lot, a year can be too long to go without basic suspension service.
 

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Discussion Starter · #5 ·
You can keep riding, but your fork is likely due/overdue for service.
FOX specifies 30hr ride time intervals for fluid changes.
Seal replacement can vary greatly, sometimes they need replaced in 30hrs, sometimes they last months/years.
That residue you are seeing is an indicator that fluid is leaking past the seals.
If it's dark and dirty looking, it's likely your suspension fluid is dirty as well.
If you ride a lot, a year can be too long to go without basic suspension service.
That's odd because this didn't start until after I serviced it. I ride about 2 times week.

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Did you install the seals upside down?

I'm in the suspension service business so that black gunk looks like money to me!

I'd open that sucker up right away and check it. Most wear occurs below the waterline so is usually invisible from up top.

mk
 

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I have similar problem.

I installed Enduro seals to Manitou Tower. I used Fox green oil for stanchion lube and Rock'n'Roll Super Slick as assembly lube. I've used this combination of oils earlier on the same fork with stock seals and also on Fox fork without problems.

After second or third ride I noticed some black sticky stuff on stanchions. It makes the fork really sticky. I cannot rub it off with finger, but I can clean it easily with Brunox Deo.

One difference between stock Manitou seals and Enduro seals is lack of foam rings. Before the last ride I turned the bike upside down as recommended by Enduro instructions to let the stanchion lube to get into upper bushings, but that didn't stop the black stuff to appear.

My current theory is that the lack of foam ring leaves stanchions dry at seals/upper bushings and the black stuff I see is rubber from seals. Another alternative is that it is Rock'n'Roll lube that has black color, but I do not find this very likely, because it has not caused similar problems earlier.

Any other similar experiences? What was the solution? Should I go back to original Manitou seals?
 

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I recently had a similar experience with Enduro seals. The black rubber seals you put in after the foam rings are dry.

Fixed mine by putting the bike upside down, lowering a few psi and cycling the fork up and down a bunch of times. Let it sit there and did it again. This gets the oil to lubricate the internal black oring seals. The oil doesn't reach them otherwise.
 

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Time to service the fork ASAP. I'd also prise up the blue scrapers and clean out under them. They are tough enough to do that without damage. During the service make sure you get oil into the foam rings before assembly and you clean/grease the seals too. The Enduro seals for FOX do have foam rings. The Enduro seals for Manitou don't.

I've run Enduro seals on Manitou forks for years without issues. Oil does get up the top without problems. If your seal ever leaks that becomes obvious.
 

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Thank you for suggestions. I will definitely open up the fork and see how it looks like inside, even though it has less than 12 hours of usage after complete servicing.

This is Manitou fork, so I do not have foam rings under the Enduro oil seals. Since the bike was standing couple of months after the fork servicing, it is likely that all the oil is in the bottom of the fork legs. I'll try the procedure that norcom suggested and cycle the fork in upside down position.
 

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I have similar problem....
My current theory is that the lack of foam ring leaves stanchions dry at seals/upper bushings and the black stuff I see is rubber from seals. Another alternative is that it is Rock'n'Roll lube that has black color, but I do not find this very likely, because it has not caused similar problems earlier.
I can't say what it is, but I'm pretty confident on what it's not:
1) Very unlikely it's material from the oil seal. It would take very little oil seal material to wear away before oil was flooding out. The sealing lip has a very defined shape and wearing it down with the loss of that much material would ruin that sealing edge.
2) Not likely it's the Super Slick grease. If it were, it would be greasy, not gummy.
In the pic, I see a lot of fine dust on the back of the white arch. Is there any possibility that it is fine dust sticking to the stanchion tube? Maybe the tube is exceptionally dry and the wiper is not scraping it off?
Definitely follow Dougal's recommendation to remove the blue wipers and look inside.
Be sure nothing as accumulated between the oil seal and wiper.

Other posts on this thread have referred to the black oil seals as being dry. During assembly, it's important to pack Super Slick grease (or Slick Honey) into the "pocket" of the inside surface of the oil seal.
 

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I rushed home and opened up the fork. Here are the findings:

1) oil: https://home.cyber.ee/arne/towerlegs/oil.jpg

More on the right side, less on the left side. I think the grease on the spring side swallowed some of the oil. Oil seems ok (Fox Green). It is not clear because some of the Super Slick grease is dissolved in it. The small dots are also Super Slick. There seems to be no hard particles in the oil.

2) stanchions: https://home.cyber.ee/arne/towerlegs/stanchion.jpg

Stanchions were clean. So it is possible that the black residue was realy only on the outside of the seals. There were some circles on both legs - they were barely visible and seemed to be aligned with the location of inner oil seals. I'm not sure if they were there already before I switched the seals.

3) left seals https://home.cyber.ee/arne/towerlegs/left1.jpg

There was no dirt inside the seals. There was small amount of Super Slick between oil seal and blue wiper.

4) right seals

https://home.cyber.ee/arne/towerlegs/right1.jpg
https://home.cyber.ee/arne/towerlegs/right2.jpg
https://home.cyber.ee/arne/towerlegs/right3.jpg
https://home.cyber.ee/arne/towerlegs/right4.jpg

There was much more Super Slick between oil seal and blue wiper. But no dirt was visible. The right stanchion was also in much worse condition than the left one. You can also see some dark stuff on bushings. Most of it came off easily and seemed to be Super Slick. But even cleaning with isopropanol alcohol left some dark patches. I do not remember how the bushings looked like before I switched the seals.

Is it possible that some of the Super Slick that was between oil seal and blue wiper moved out, mixed with dust and formed this black stuff. We have had dry weather for almost a week and there is lots of very fine dust everywhere.

Should avoid putting the Super Slick between oil seals and blue wiper?
 

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Should avoid putting the Super Slick between oil seals and blue wiper?
The wipers you have are what we call "next generation." That means the blue wiper has no sealed "pocket" between an upper and a lower lip. There is only a leading/scraper edge at the top. We used to recommend packing some extra grease in that "pocket" on the older style wipers. We now only recommend in the oil seal pocket. The blue wiper will keep junk out of the fork, but has no mechanism (by design) to keep anything in the fork (that's the oil seal's job). So, yes, on the one side that was heavily loaded with grease, small rings of grease could have been mixing with the fine dust. According to the pics, everything inside the fork looks great other than excess Super Slick. As far as the grease that got into the splash bath oil, it's not a serious problem (would be a bigger deal in a damper).

Not every stanchion coating is the same. Ideally, the pores of the coating retain some of the oil they contact while inside the lowers. Sometimes this property can even vary between batches. In cases where the stanchions seem to be particularly dry, you might want to use a bit of Stanchion Lube by Finish Line. This is essentially a liquified Teflon that does not leave a dust-attracting coat like greases and suspension oils do. I recommend using it at least during the initial break-in period of your seals.
 

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I would say your oil is too thin also and not suited for bath use. I get far better results with oil that is much thicker and clings better. Current favourite is Motorex SuperGliss. However I haven't tried that oil with the Enduro seals.

The Manitou Semi-Bath oil (also made by motorex) is excellent too.
 

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I would say your oil is too thin also and not suited for bath use. I get far better results with oil that is much thicker and clings better. Current favourite is Motorex SuperGliss. However I haven't tried that oil with the Enduro seals.

The Manitou Semi-Bath oil (also made by motorex) is excellent too.
Thanks, Dougal, that is also a good point. Fully synthetic motor oil like Mobil1 has worked very well in splash bath applications for us and is another good choice to consider.
 

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Thanks, Dougal, that is also a good point. Fully synthetic motor oil like Mobil1 has worked very well in splash bath applications for us and is another good choice to consider.
That one gives some regional headaches. The Mobil1 I can buy here is completely different spec and viscosity to that sold in the US.
I also couldn't find it in small enough or cheap enough bottles to consider experimenting with, so I've never actually tried it.
Almost every other motor oil I tried from my own stock was awful. The exception being the Motorex fully synthetic that was rumoured to be close to Manitou/Motorex semi-bath. That was very good, but Supergliss was even better.

I do have a drum of Supergliss arriving any day now (420L of oil all up). That should see me and my customers right for a few years.
 

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That one gives some regional headaches. The Mobil1 I can buy here is completely different spec and viscosity to that sold in the US.
Wow. That makes no sense. Whatever the reason, if the formulation is different from region to region, I guess I will quit making a blanket recommendation for the Mobil1. I've personally had very good results with Amzoil fully synthetic motor oil. Similar to what you said about the Motorex Supergliss, the synthetic motor oil sticks to the moving parts much better than regular fork oil. I would like to add the Supergliss to products I recommend, but it appears it is only available in 5L or larger containers. If that's correct, it's not going to be a practical recommendation for for most end users.
 
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