I am setting up for my first fork seal replacement. Just as I pass 10k, it seems like it's time with the right starting to leak a little bit. I am checking out the how-to's and browsing for the parts I will need. One question I have looks to be completely obvious, but curious if anyone has tried it: is it possible to raise the front end but leave the forks attached to the triple clamps for this task, or would that just be setting me up for a huge failure ending in nothing but frustration and injury?
The reason I ask is I wrapped my forks with vinyl, and that was something I don't want to undo and recover when I'm finished. Any FHE would be awesome.
Anything is possible but that would really make it a pain. Make sure you check the tubes for nicks, 10K is not a lot of mileage for fork seals.
As indicated, it may be a pain but I think you could get a way with it. You would want to ensure the bike is secure as you will be yanking on the tubes... I would pick up one of those $10 liquid pumps at Autozone or similar to get as much of the oil out before separating the tubes and make sure you have a pan of some sort under the bike, I've seen them at Walmart.
I think the biggest problem you are going to run into is the oil mess associated with performing the job with the tubes in the triples...
Short version: No
Long, with them in the bike you're not going to be able to accurately set the oil level. The various bleed steps will be a huge pain. Separating the pieces will be nightmarish and possibly dangerous as you're basically using the slider as a slide hammer to force the seal out once the retainer clip is out. Then there's seating the new seal, more slid-hammer like activity...
And the mess... oh my. Even if you did get the cap off and got the seal out it'd be followed by a gush of oil.
Quote from: Slide Panda on May 07, 2012, 10:40:52 AM
Separating the pieces will be nightmarish and possibly dangerous as you're basically using the slider as a slide hammer to force the seal out once the retainer clip is out. Then there's seating the new seal, more slid-hammer like activity...
not too tough to deal with the mess, but the hammering stuff sounds like it would be pretty tough. Thanks for the illustration of the fun ahead of me.
Does 10k miles seem too early to start having trouble with the seals? It's not a significant leak, but enough to collect dirt on the lower bar and draw my attention to one side that looks moderately different compared to the other side. Plus a small spot of oil on the garage floor where that one side sits, all telling me something is leaking out of that area. Unless it's the brake line (pretty sure it isn't), I don't know what else it could be.
10 seems early unless you happen to ride dirt roads a lot and pick up fine abrasive dust. Early... but nothing last forever. Easy test to see if it's oil vs brake fluid. Water will rinse away brake fluid... not oil.
And yeah - the oh so graceful method to draw out the seal is to drain the fork, slide down the dust seal, remove the oil seal retaining clip. Once that's done you grab the upper tube in one hand and the axle/caliper mount in the other and make like a slide hammer. A few of that and POP out comes the oil seal. That wouldn't be so hard to do on the bike, aside from the mess. But the installation of the new seal would be a pregnant dog as would geting the oil in and the internals bled.
Also, how where you planning to compress the legs? You need to get the cap off to separate the two fork sections.
a little leak (enough to keep the sliders "wet" but not dripping) is no big deal imo. Talking with Stuart at AMS about this very thing awhile back: So long as its not "running off" in a substantial way, or flowing into the brake pads (contaminating them), etc, its not really something to be concerned with. Certainly not worth the work/labor to replace the seal at that point.
Your puddle on the floor is something to maybe further investigate, if that's the case then it is something to look into.
Besides dirt/debris and high mileage/wear, blown fork seals can occur from bottoming the forks out and forcing the fluid to go "somewhere" - this can occur from weak springs and rough roads, landing wheelies to hard, or cranking the tie-downs too tight when transporting the bike. Things to think about.
There are some good supplies, tools, and educational materials from RaceTech and Traxxion Dynamics for fork work. I would suggest acquiring a bit of educational material before diving into one of these jobs if you are a diy'er.
I didn't see what bike you had (not in original post or I missed it, and not in your signature or profile info), but this may present an opportunity (to spend money... on something worthwhile). At 10K mi, you are not likely in "need" of new fork oil, but this would be a chance to replace the old with something new and more suited to your riding habits. If you are disassembling the forks, you may want to look into respringing it for your weight (and make sure to set sag - static & w/ rider - once put back together). So that's the short list: Do the seals, look into fork oil weights and spring rates. If you have adjustable forks, you may consider revalving it, but that's not necessary (at all) for most street riders - if you are track-daying and generally a hard rider (objectively hard, not subjectively hard - everybody thinks they are just like rossi to some extent), then maybe consider the valves - they are not cheap. They are also a good deal more complex since there are shim stacks and whatnot to consider.
I had a relatively new seal start weeping and Bruce Meyers suggested a business card slid between the seal and tube would dislodge the debris and put things right.
Worked like a charm.
bcard slides in, then remove it, and voila - no more leak?
one of the things the good suspension shops do when working on forks is polish up the sliders, make sure there are no burrs, etc. After 10k mi, probably not very relevant UNLESS you are going to be pulling things apart...
Quote from: j v on May 08, 2012, 08:24:56 AM
bcard slides in, then remove it, and voila - no more leak?
one of the things the good suspension shops do when working on forks is polish up the sliders, make sure there are no burrs, etc. After 10k mi, probably not very relevant UNLESS you are going to be pulling things apart...
It worked for me.
And yes...the tubes were spotless when the seals were replaced. It's tough to polish TiN coated Showas. The plating is very thin.
I am planning to do springs and change the weight of the oil at the same time if I do have to take them apart. The more I think about it, that seems as good a reason to start the project as any. Searching through race-tech's website, I found 2 different classifications that seemed to work for my bike. Mine is a 2002 Monster 750ie Dark; the options are "750 Monster dark - 1999-2001" or "Monster 750 D-S - 2002". When I called the local shop (not the racetech number) for insight, he told me the 99-01 was my only option, but I thought it was weird.
The Spring part numbers (and I'm sure seals) are different, and the one pertaining to my year has Marzocchi 43U forks listed, whereas the other possibility has Marzocchi 40U listed. Any insight to this? I don't want to get to that point and realize I have the wrong parts.
i'm not certain, but i'd say "very confident" that you want the 43U bits. The numbering on their website (RaceTech's) is wonky and doesn't really match up with the change in forks from my recollection. The small-front axle forks (with 40mm caliper mount) went away in 2000. But the frame didn't change till 2002. They seem to have mixed the data, but perhaps they are using some other figure for reference. Off the top of my head, I do not "know" exactly which parts are the same and which parts are different inside the forks.
'02 M750 is 43mm forks.
Quote from: Speeddog on May 12, 2012, 10:11:21 AM
'02 M750 is 43mm forks.
Thanks for the clarification [thumbsup]
Also, is there a discussion on fork oil weight somewhere? I've seen people mention different values, but not sure which is the normal vs. an "upgrade."
well.... depends on you to some extent. You can search on fork oil weights and see lots. Its hard to compare manufacturer X's numbering to manufacturer Y's, though.
When I did mine I went with a light medium oil, I'll probably never need to be overly concerned with the loss of viscosity with working the forks & hotter temps.
Hey folks! Sorry to reanimate a topic clearly resting so peacefully.
I'm trying to rebuild my forks and am having a beast of a time get this retaining clip out. Any pointers?
Edit: These are the Marzocchi forks from a 99 Ducati Monster 750
Thanks!
ts
Quote from: tshearman on July 10, 2015, 11:40:55 PM
Hey folks! Sorry to reanimate a topic clearly reading so peacefully.
I'm trying to rebuild my forks and am having a beast of a time get this retaining clip out. Any pointers?
Edit: These are the Marzocchi forks from a 99 Ducati Monster 750
Thanks!
ts
needle nose pliers if they're "sutck" . . . shouldn't be sho hard to take them off
Hopefully I'm trying to pull the right thing out of there. On these forks the retaining clip is round and an approximately (5/6th or so) circle with a squarish cross section. No abrupt bends, essentially a smooth partial circle.
Also, this is the case on both forks. Logic then suggests I'm doing something wrong...
Steps so far:
Removed from bike
Removed top bolt
Removed 1/2 ring retainers (by compressing the spring)
Removed spring, spring sleeve and slider
Now I have the fork tube with dust seal removed and am delicately trying to remove the retaining clip. Unfortunately I may have added a bit to the topology of the outer fork tube... Expletive.
Update: Finally got them off. It involved (as recommended) a pair of needle nose pliers, partial destroying the existing fork seal in order to get a good grip on them, grabbing them as hard as possible and yanking them out. It was by no means easy.
On a related note, I bought the wrong sized fork seals (from Ebay... ugh). Does anyone know a reliable place to buy fork & dust seals? RaceTech was mentioned.
Edit: 1999 Ducati Monster 750
Thanks!
ts