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  1. #1
    Senior Member TimJ's Avatar
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    1997 Manitou forks rebuild HELP

    I need help putting some old Manitou shock back together. Here's a couple photos:





    As you see they're pretty darn old, they were made for canti's. What I'm trying to do is just a simple rebuild, not refurbishment, just clean it up as best I can and put it back together. These are going on a bike I don't want to spend money on that has even older forks that are completely busted.

    Let me describe the situation: I took these apart and a good amount of oil came out of the lower leg in the photo. The upper leg, someone put in something caustic or something because the bumper on the bottom there has disolved quite a bit. There was a bunch of black gunk around it and the bumper isn't solid any more. Inside the lower leg is a spring and another bumper or two, like the upper leg's insides, but a shorter stack. What I mean is that bare metal rod on the lower assembly, if it would have come out altogether would have a spring and a bumper on it like the upper assembly, but it's not as long.

    I have a maintenence book that shows an example of a sprung fork being rebuilt and basically the directions are to grease the springs, inject oil into the bottom of the legs, screw in all the screws so it doesn't leak out, then inject oil into the upper part of the legs and seal everything back up. So what I was thinking I'd do is this: try to get a new bumper that will work well enough to replace the disolved one (it seems to be the bottom-out bumper). Grease the springs, put the assembly's back in the legs, put oil in the bottom, put oil in the top, put back together, lube the stanchions with a teflon lube, call it good.

    Does that sound about right? But- if I grease the springs with say Phils, if oil gets through won't it thin out the Phil's too much? So should I grease with a synthetic grease?

    Help would be appreciated. It's an older bike but actually pretty nice- chromo frame, LX components, but this isn't going to be my permanent ride so I just want to get it going with the fork I have on hand. Thanks.
    Last edited by TimJ; 06-27-07 at 04:42 PM. Reason: clarification
    fun facts: Psychopaths have trouble understanding abstract concepts.
    "Incompetent individuals, compared with their more competent peers, will dramatically overestimate their ability and performance relative to objective criteria."

  2. #2
    Non Tribuo Anus Rodentum and off to the next adventure (RIP) Stacey's Avatar
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  3. #3
    Senior Member TimJ's Avatar
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    It's older than everything listed there. The only indication of model I've seen on it is on the bottom of one of the cartridges "comp pro" is written. I've looked at a couple older ones but unfortunately the script on the exploded views is illegible, so I don't completely understand the directions (can't see what they refer to).

    Basically if someone could give a best guess as to the appropriate way to reassemble these that'd be enough. Reading through different service guides it seems that the lower assembly is probably the damping assembly, and the upper is the spring. I just don't know if oil is used in both assemblies or just the damping, or if the damping gets oil at the top and bottom and the spring just gets it at the bottom... do I grease the damping assembly or just use oil? How much oil? Different guides I've read say different things and I don't know what is right for this fork.
    fun facts: Psychopaths have trouble understanding abstract concepts.
    "Incompetent individuals, compared with their more competent peers, will dramatically overestimate their ability and performance relative to objective criteria."

  4. #4
    Senior Member TimJ's Avatar
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    OK, so I found this:

    http://users.actrix.co.nz/dougal.ellen/forkfaq.html

    Which is some dude's page about older Manitou forks. I'm going to go off of this for putting these forks back together. But I don't understand all the lingo. For instance:

    Manitous first dampers arrived in 95 and were through shaft cartridges built into the lower part of one stanchion tube. They use one piston on a shaft which enters the bottom of the damepr and extends through the other side. The result is speed sensitive (through shims on the piston) and rebound adjustable.

    In 1998 The TPC (twin piston chamber) damper was introduced in the SX and Xvert forks.
    The TPC damper occupies a whole stanchion tube. The lower (rebound) piston is fixed to the damper shaft which moves through the oil. The damper shaft displaces oil which makes the oil surface rise and moves oil through the stationary upper (compression) piston.
    I don't know which type my fork has, I can't tell from the description because I'm not famililar with all the lingo. He has directions how to rebuild the non-tpc dampers and then for the TPC dampers just says all you need to do is put fresh oil in.

    So... does anyone know which type of damper is pictured above?

    Again, if someone could give me some general directions as to how much oil I ought to put in and where (I still don't know if I'm supposed to oil the spring assembly (the upper assembly in the photo) or just the damping assembly.
    fun facts: Psychopaths have trouble understanding abstract concepts.
    "Incompetent individuals, compared with their more competent peers, will dramatically overestimate their ability and performance relative to objective criteria."

  5. #5
    Senior Member TimJ's Avatar
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    More info, I think I know the model. From some website a short description:

    1997 Manitou FS ...the FS, (white, 76mm travel, two way oil damped, oversized bulge legs).
    Sounds like my forks since they say FS bulge cartridge on them (I thought that was a description, not the actual model name).

    So two way oil damped... I guess this would not be the TPC system and I ought to follow the directions on that guy's site for the older shocks. Still, I have no idea what to do with the spring side except grease the springs.
    fun facts: Psychopaths have trouble understanding abstract concepts.
    "Incompetent individuals, compared with their more competent peers, will dramatically overestimate their ability and performance relative to objective criteria."

  6. #6
    Non Tribuo Anus Rodentum and off to the next adventure (RIP) Stacey's Avatar
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    Tim, I can't be much help to you here. My experience with telescopic forks is limited to motorcycles. Plain old coil & oil forks that you drained, disassembled, cleaned, reassembled and rode. The gimmicks that these bike fork companies are spoon feeding the bicycle consumer are unbelievable.

    Each fork is speced differently for oil viscosity and levels. 7.5 wt fork oil would be a good place to start, the amount is anyones guess. A bit of grease on the outside of the coils wouldnt hurt, I guess. We never did it on motos.

    Good luck with it.

  7. #7
    Senior Member TimJ's Avatar
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    Thanks for the input anyway.
    fun facts: Psychopaths have trouble understanding abstract concepts.
    "Incompetent individuals, compared with their more competent peers, will dramatically overestimate their ability and performance relative to objective criteria."

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