I noticed SKF makes 35mm inside diameter seals for KTM 65 motocross bikes. Anybody know the outside diameter and depth of these, and will they fit a 35mm stanchion Boxxer? What are the stock seal dimensions of a Boxxer?
SKF seals for Boxxer?
- Thread starter Verskis
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I'm also very interested in this!!!
Found this one on a swiss site:
http://www.fdsl.ch/docs/Bilder/SKF_Web_Liste.pdf
Found this one on a swiss site:
http://www.fdsl.ch/docs/Bilder/SKF_Web_Liste.pdf
I know guys were taking Fox 32mm seals and putting them on their 32mm Boxxers with success. I've got some 32mm SKF seals laying about that I'm considering trying on my 32mm Boxxer to see if there is any difference.
So will 35mm marzocchi seals fit at 2010 35mm boxxer?
35mm Boxxer oil seals are 35 x 45 x 7mm.
35mm Boxxer wipers are 35 x 45 x 8mm.
The closest SKF seals would be the 35mm Marzocchi moto fork seals (35 x 47 x 10mm) and as far as I can tell they would also fit the other 888.
Bummer.
35mm Boxxer wipers are 35 x 45 x 8mm.
The closest SKF seals would be the 35mm Marzocchi moto fork seals (35 x 47 x 10mm) and as far as I can tell they would also fit the other 888.
Bummer.
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i put some in my 32mm boxxer. it made a world of difference!
I always though the 35mm boxxers oil seals were 35/45/7...
You're right, typed that in wrong.
32mm Boxxer with SKF's is just the SKF seal and foam ring. Setup the same way as the Fox forks as well as every other 32mm Rockshox fork except the Boxxer.
I don't see it creating an issue.
I don't see it creating an issue.
I don't see the point in installing an SKF seal in a 35mm Boxxer unless it is going to be the same config/design as the Fox setup (i.e. one seal for both pressure and wiping requirements, thus less lips against the shaft.. *giggle*).
Simply replacing the oil seal with an SKF (even if one did fit) and running it with the RS wiper would likely produce no benefit besides placebo / the improvement in stiction made by a service alone.
Different story on the 32mm obviously, as you can fit the proper seal from a 32mm Fox.
Simply replacing the oil seal with an SKF (even if one did fit) and running it with the RS wiper would likely produce no benefit besides placebo / the improvement in stiction made by a service alone.
Different story on the 32mm obviously, as you can fit the proper seal from a 32mm Fox.
^I'm assuming seal was used incorrectly in the above posts to actually describe the dust wiper opposed to the oil seal.
I recently got a hold of a couple 35mm foam rings (oil seals) to try out on the boxxer. I'm only replacing the spring side seal because the dampening is an avalanche cart. Maybe I'm wrong but my thinking is that the pressure caused by the open bath of the dampening would be too great for just a foam ring and wiper.
I recently got a hold of a couple 35mm foam rings (oil seals) to try out on the boxxer. I'm only replacing the spring side seal because the dampening is an avalanche cart. Maybe I'm wrong but my thinking is that the pressure caused by the open bath of the dampening would be too great for just a foam ring and wiper.
Yeah maybe you're right. Shame the OD is 47mm then, the extra height wouldn't have been a problem.
The only thing that matters in your scenario is the air volume left inside the leg at bottom out (thus the pressure) - the damper itself nor its style of damping will have any direct effect on it - however because open bath dampers usually use a lot of oil, volume at bottom out probably is low enough that it would need an oil seal.
If it's a coil fork, then there is a lot of volume in the spring leg even at bottom out, so it's safe to run a foam ring in place of the pressure seal in that leg. I wouldn't do it on an air spring leg though.
The only thing that matters in your scenario is the air volume left inside the leg at bottom out (thus the pressure) - the damper itself nor its style of damping will have any direct effect on it - however because open bath dampers usually use a lot of oil, volume at bottom out probably is low enough that it would need an oil seal.
If it's a coil fork, then there is a lot of volume in the spring leg even at bottom out, so it's safe to run a foam ring in place of the pressure seal in that leg. I wouldn't do it on an air spring leg though.
I think I would tend to agree with Udi on the open bath/sealed damper, however the one piece of info that plays devils advocate here is that even on Fox's open bath forks, the use only a foam ring and dust wiper.
I've installed SKF seals on 2 pair of the old Talas XXT or XTT(whatever those threshold forks are). They were open bath and the SKF's worked great even at full compression they weren't moving.
I happened to be dropping the travel on a RS fork recently and dropped the pieces. I flipped one of the air spring bits which prevented are from entering the negative chamber. The air was filling the lowers instead of the negative spring. I got it to 100psi before the dust seal started to move(dust wiper/foam ring on that fork from RS). I'm curious how much pressure develops during compression?
I've installed SKF seals on 2 pair of the old Talas XXT or XTT(whatever those threshold forks are). They were open bath and the SKF's worked great even at full compression they weren't moving.
I happened to be dropping the travel on a RS fork recently and dropped the pieces. I flipped one of the air spring bits which prevented are from entering the negative chamber. The air was filling the lowers instead of the negative spring. I got it to 100psi before the dust seal started to move(dust wiper/foam ring on that fork from RS). I'm curious how much pressure develops during compression?
fox seals are both oil and dust seal in one, while rs/marz use separate oil/pressure seal and dust seal, also i don't think fox seals would hold a lot of pressure, that's not what they are designed for nor they have any sort of retainer to hold them in place at higher pressures.
from what i've been reading around the interwebz, it would seem that the rs dust seal is to blame for the stiction. too bad i no longer have my old pike to mess around with. i guess someone could experiment with popping the dust seal and riding with it on top of the stanchion to see if there's more small bump sensitivity if there's not too much dust and other flying crap around.
from what i've been reading around the interwebz, it would seem that the rs dust seal is to blame for the stiction. too bad i no longer have my old pike to mess around with. i guess someone could experiment with popping the dust seal and riding with it on top of the stanchion to see if there's more small bump sensitivity if there's not too much dust and other flying crap around.
One thing that might be worth considering (esp. for the 35mm boxxer crew without Fox seals available) is that there are surplus sealing lips in a twin-seal setup. You can remove the lower lip of the dust wiper safely, and likely the upper lip of the oil seal also - thus halving the number of lips sliding against each stanchion externally. A hobby knife or similar would work, obviously being careful not to harm the useful lips that you want to keep. A little more detail below.
baca262 -
I think most here understand the difference between the seal configuration, and for whatever it's worth, RS don't use any sort of retainer to hold them in place either - thus under excessive pressure they can blow right out of the fork.
I'd be inclined to agree with you that the twin-seal setups would hold more pressure (Marz moreso, with the retaining clip), however the retainer aside, there's no reason that a properly designed single seal couldn't perform both tasks equally as well. If you consider how the seals are built (when using separate pressure/wiper seals), the dust wiper has a surplus pressure sealing lip on the base, and the pressure seal has a surplus wiper lip on its top. The wiper base is attempting to seal an area under no pressure, and the pressure seal top is wiping something that has already been wiped. Integrating the two seals into one should essentially work just as well if done correctly. This also explains my suggestion above.
BmxConvert -
Yeah like I said, I don't think the type of damper itself has any bearing on it. It would all be to do with the volume (and thus pressure) at bottom out, and whether the sealing mechanism can support it. Support actually has to be provided in two ways, one is to stop pressure leaking between the seal and the stanchion, and the other is to stop the seal from blowing out of the casting - both equally important. That could be tuned with seal-to-lower insertion tolerances, internal air volume, and seal design itself.
Because of that, I think it's difficult to draw parallels between different forks / different brands - as the reason "it works" could vary from case to case.
You might find it interesting that greased vs. dry seal installations (outer surface of seal against casting) on RS forks will support different pressure loads before the seals pop out. Tolerances there vary from fork to fork as well.
baca262 -
I think most here understand the difference between the seal configuration, and for whatever it's worth, RS don't use any sort of retainer to hold them in place either - thus under excessive pressure they can blow right out of the fork.
I'd be inclined to agree with you that the twin-seal setups would hold more pressure (Marz moreso, with the retaining clip), however the retainer aside, there's no reason that a properly designed single seal couldn't perform both tasks equally as well. If you consider how the seals are built (when using separate pressure/wiper seals), the dust wiper has a surplus pressure sealing lip on the base, and the pressure seal has a surplus wiper lip on its top. The wiper base is attempting to seal an area under no pressure, and the pressure seal top is wiping something that has already been wiped. Integrating the two seals into one should essentially work just as well if done correctly. This also explains my suggestion above.
BmxConvert -
Yeah like I said, I don't think the type of damper itself has any bearing on it. It would all be to do with the volume (and thus pressure) at bottom out, and whether the sealing mechanism can support it. Support actually has to be provided in two ways, one is to stop pressure leaking between the seal and the stanchion, and the other is to stop the seal from blowing out of the casting - both equally important. That could be tuned with seal-to-lower insertion tolerances, internal air volume, and seal design itself.
Because of that, I think it's difficult to draw parallels between different forks / different brands - as the reason "it works" could vary from case to case.
You might find it interesting that greased vs. dry seal installations (outer surface of seal against casting) on RS forks will support different pressure loads before the seals pop out. Tolerances there vary from fork to fork as well.
Also just a disclaimer / tip if anyone decides to give that a go - when it comes to RS forks, in my experience dust wipers are generally reusable, however pressure seals are not. If you remove the stanchion from the seal and then reinstall it without using a new seal, there will be a tendency for it to leak. Occasionally it might work fine, but often it will not.
Thus, if giving this a go, I'd suggest (at least) using a new set of pressure seals - 35x45x7 or 32x42x7mm 'rotary shaft seal' at your local seal shop.
FWIW - I've only tried removing the lower lip of the dust wiper personally, and it worked great with no ill-effects that I could notice. Theoretically, removing the upper lip of the pressure seal should also be fine but I haven't tried it, if someone does, feel free to post how it went. Keep in mind if doing this, it should be done on a new pressure seal prior to installation.
Thus, if giving this a go, I'd suggest (at least) using a new set of pressure seals - 35x45x7 or 32x42x7mm 'rotary shaft seal' at your local seal shop.
FWIW - I've only tried removing the lower lip of the dust wiper personally, and it worked great with no ill-effects that I could notice. Theoretically, removing the upper lip of the pressure seal should also be fine but I haven't tried it, if someone does, feel free to post how it went. Keep in mind if doing this, it should be done on a new pressure seal prior to installation.
i have the avalanche cartridge in my fork, and no issues. i mixed up and overfilled the crap out of my fork (to the point is would hydrolock at about 6" of travel) and it didn't spit out any seals.
correct me if i am wrong, but on an air sprung boxxer (or most any other air fork), shouldn't the air pressure only be in the upper tube (stanchion)? the negative spring at the bottom should also act as the lower air seal. thus there should be no more than ambient air pressure in the lowers of the fork and no additional risk to popping a seal out...
correct me if i am wrong, but on an air sprung boxxer (or most any other air fork), shouldn't the air pressure only be in the upper tube (stanchion)? the negative spring at the bottom should also act as the lower air seal. thus there should be no more than ambient air pressure in the lowers of the fork and no additional risk to popping a seal out...
you're right but you haven't accounted for the volume reduction when the stanchion goes in, that builds up pressure.
didn't know boxxers didn't have the foam rings, never actually took one apart. i assumed their whole fork lineup used foam rings for seal lubrication.
didn't know boxxers didn't have the foam rings, never actually took one apart. i assumed their whole fork lineup used foam rings for seal lubrication.
descente -
As baca pointed out the difference is that the air sprung stanchion is sealed off at the base (or close to the base) thus the volume in the lowers at bottom out and thus internal pressure is quite high. Compare this to the coil boxxer which is open to air at the base of the stanchion, thus has a greater volume and lower pressure in that leg.
baca -
There's no real benefit to a foam ring above an oil seal as the oil can never reach it to soak it. I know they used one in the Pike, but the Boxxers don't have them. I think it makes more sense to have a foam ring in a single-seal fork as it's constantly hit with oil and helps keep the seal and upper bushing lubed.
As baca pointed out the difference is that the air sprung stanchion is sealed off at the base (or close to the base) thus the volume in the lowers at bottom out and thus internal pressure is quite high. Compare this to the coil boxxer which is open to air at the base of the stanchion, thus has a greater volume and lower pressure in that leg.
baca -
There's no real benefit to a foam ring above an oil seal as the oil can never reach it to soak it. I know they used one in the Pike, but the Boxxers don't have them. I think it makes more sense to have a foam ring in a single-seal fork as it's constantly hit with oil and helps keep the seal and upper bushing lubed.
I understand that, and what you said actually applies to a lot of RS singlecrown forks too - but you're missing the point, without calculating the actual volume of the lowers you can't say "it works in fork x, so it'll work in fork y".
Even little things like a cavity in the casting below the stanchion's bottom out point, or area between the outside of the stanchion and the casting, or the space between bushings. These can all change the final volume at bottom out significantly. Also, given that seals aren't clip-retained in RS forks (and varying tolerances) you might have a blowout in a fork of the same model as another that didn't.
Anyway by all means if you want to try it then go right ahead, the worst that can happen is a leak, and if it works - great!
Even little things like a cavity in the casting below the stanchion's bottom out point, or area between the outside of the stanchion and the casting, or the space between bushings. These can all change the final volume at bottom out significantly. Also, given that seals aren't clip-retained in RS forks (and varying tolerances) you might have a blowout in a fork of the same model as another that didn't.
Anyway by all means if you want to try it then go right ahead, the worst that can happen is a leak, and if it works - great!
So I got some of the new Fox SKF seals (32MM) that came in. I put them in a 2008 boxxer team. they do in fact work but I can't give any opinion of them since all I did was ride around on the road so far. There seems to be a slight noticeable reduction in stiction but expect them to break in a little bit with some actual riding.
I got the right side fully seated but I couldn't get the left fully seated since I was using ghetto tools(an outboard BB installer). Does anyone know what size tube/etc should be used that will contact the outer part of the seal to properly seat it. It is about .5mm from being fully seated in the fork but I couldn't get it all the way. I'm hoping I can get a PVC tube that is the right size so I can pound the seal down a little bit more without taking the fork apart again.
right seal
Edit: never mind I found some PVC that was the right size and everything seated perfectly.
Fork seems to have a great deal less initial stiction than before with the OEM Boxxer seals.
left seal
I got the right side fully seated but I couldn't get the left fully seated since I was using ghetto tools(an outboard BB installer). Does anyone know what size tube/etc should be used that will contact the outer part of the seal to properly seat it. It is about .5mm from being fully seated in the fork but I couldn't get it all the way. I'm hoping I can get a PVC tube that is the right size so I can pound the seal down a little bit more without taking the fork apart again.
right seal
Edit: never mind I found some PVC that was the right size and everything seated perfectly.
Fork seems to have a great deal less initial stiction than before with the OEM Boxxer seals.
left seal
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I am running an Elka cartridge in my 35mm Boxxer world cup. Everything still felt a little sticky running both oil and dust seals so I decided to try running just dust seals with slick honey as lubrication in lowers and bushings. I installed the dust seals with alcohol which evaporates of course and I compressed the fork almost all of the way before tightening the lower bolts effectively reducing the volume of air inside the fork below the seal head(damper side has no seal head with elka cartridge). The initial stickiness is almost gone however the big difference is how it feels going over fast braking bumps and rocks. There is almost no stickiness at all.
I took three runs down the local dh trail and had no issues with the dust seals blowing out. The concern of course is how well the slick honey will do with temperature and with long term lubrication as an oil substitute. I am sure that I will need to pull the lowers after a hard day of riding which isn't a big deal I can just do it after work(bike mechanic). I will probably go back to dust and oil seals I was just curious if this setup would work.
I took three runs down the local dh trail and had no issues with the dust seals blowing out. The concern of course is how well the slick honey will do with temperature and with long term lubrication as an oil substitute. I am sure that I will need to pull the lowers after a hard day of riding which isn't a big deal I can just do it after work(bike mechanic). I will probably go back to dust and oil seals I was just curious if this setup would work.
use fox foam rings where the "oil" seals used to be. soak em with float fluid. your lubrication problem is solved.
hey guy,
any update on this? I wouldn't mind putting together a new fork, and the idea of an avy cart'ed boxxer came up, but I'd like to make sure it has seals that work.
I mounted up the 32mm SKF seals in both my Boxxer Team and my Boxxer WC. I rode them for a bit with no issue. I've since switched back to a 35mm Boxxer WC and sold the 32mm Team and WC. Both forks are still running strong with no issues.
Sounds promising.. I'm wonder if you run the fox foam rings with the green fluid in the bottom would work..
Anyone run the 32mm on a RS fork other than the Boxxer? Thinking about these for the Revelation on my XC bike.
Swapped them out on my pike w/arygle lowers, def. noticeable difference, smooth/plusher..
Are you running the RS oil seals with the fox dust seals or did you take all the RS parts out and just use all the fox parts?
Looks like RS is testing some new seals for the 35mm Boxxers.
http://www.bikeradar.com/mtb/gallery/article/new-suspension-tech-from-rockshox-and-fox-33468/14
http://cdn.mos.bikeradar.com/images/news/2012/03/19/1332150510380-1ayih8aqsh2ae-670-75.jpg
http://www.bikeradar.com/mtb/gallery/article/new-suspension-tech-from-rockshox-and-fox-33468/14
http://cdn.mos.bikeradar.com/images/news/2012/03/19/1332150510380-1ayih8aqsh2ae-670-75.jpg