[macker434172]

I've got a 1993-1995 Stumpjumper (not quite sure on year) with a Pro x cartridge Manitou front shock.

I'm trying to find a rebuild kit but not having a lot of luck. Do you guys have any suggestions? I'd really appreciate any advice you can give. The bike has been used quite a bit and needs some work to get back in good shape. I am trying to decide if it is worth fixing up or buying a new bike.


Thanks

 

[tenbsmith]

wow, that is a pretty ancient rig you're trying to fix up. You could contact Manitou support and see if they can help you.

Seems there are a couple of variables which affect the fix-up versus buy-new decision. For example, if budget is not an issue and ride quality is important, definitely buy new. If money is tight and there aren't too many things to fix, you may want to fix it.

Probably better to put money in a new bike unless you are rebuilding for senti

 

[Dougal]

You won't need a "rebuild kit", you won't need more than orings and oil. Most likely just oil.

There are manitou cartridge rebuild instructions on my www.dougal.co.nz website. The manitou cartridge dampers first arrived in 1995 with the EFC, the Pro C fork was a 97 model with a non-adjustable damper cartridge.

 

[macker434172]

Thanks for getting back to me. The parts to fix most of the issues aren't that much but fixing or replacing the fork is where the real money potentially lies. The shock hardly compresses. Dougal: what do you think that could mean? Would o rings and oil fix that?

 

[Dougal]

Those were mainly MCU elastomer forks with a short spring in them. If they don't move the first thing is to pull the lower legs (undo lower bolts, legs pull off) and see how everything looks/feels. The lowers are grease lubed so there should be no mess involved with that.

Then undo the caps and pull out the MCU/spring stacks, see how they look. Any MCU's that have distorted out of shape will return if you microwave them for 1 minute in a cup of water.

 

[TNC]

macker, as much as I still appreciate some of the old stuff out there, I think you'll be much better served by buying a closeout fork for a low price with 2-year old technology than trying to resurrect that dinosaur...or buy a decent, more modern, used fork on the cheap. That fork will never perform nearly as good as most low end modern forks. Even a lowly Suntour or such might be better, but I wouldn't touch one of those. I had some old Specialized full suspension bikes from that era, and I wouldn't waste time trying to resurrect one for actual riding...nylon pivot bushings, steep head angles, etc. If you have a vintage reason for pursuing this, OK. I'm just now resurrecting an old 2000 Specialized Big Hit Enduro...an odd model that was quite a bit better than some of the stuff available then. And while it has a Risse full-bearing rear triangle with a very good Z150 Marz fork on it, it is just barely worth reviving for actual riding use. You can wind up sinking a lot of money into a sow's ear trying to make a purse of it before you know it.

 

[macker434172]

suspension work

Dougal: Thanks for the advice. I took the shock apart to take a look at it. Looks like it could use some work. How should I proceed? Cleaning it all up and replacing o rings?

 

[macker434172]

TNC: I agree that in the long run I am much better off buying a new bike. I am probably going to do that in 6 months to a year. I have had this bike for quite a while and my brother before me. I am hoping for around $100 bucks or so to get it back in decent shape. I priced some of the parts that it needs and it comes out to about $80. I know that it won't perform like a new bike but it gives me a decent riding experience for 6 months to a year then I think its worth it.

 

[Dougal]

Start by polishing the end of that tube with a wet rag and see how it comes up. If that's okay there's no reason you can't just refill the oil, grease it and ride away happily.

Get some slick honey grease and 5wt fork oil. There's no reason to replace orings unless they're damaged.

 

[macker434172]

Dougal: I'm about to put everything back together. Do I fill the oil from the bottom or the top and how much should I put in? I really appreciate all your help. If this works this is going to save me a lot of money. Thanks again

 

[Dougal]

Dougal: I'm about to put everything back together. Do I fill the oil from the bottom or the top and how much should I put in? I really appreciate all your help. If this works this is going to save me a lot of money. Thanks again

Follow the instructions on the dougal.co.nz site below.

Manitou through shaft dampers can be found on the first oil damped manitou, the 1995 EFC through to the 97 manitou Palmer Stroker (FS Ti).

The designs differ in small degrees throughout the models. The 95 EFC and 96 Mach V SX use one way pistons (on rebound all the oil must return through the adjustable freebleed). The 97 Pro C uses a non adjustable damper based on the 96 Mach V SX design.

All the other 96 and 97 through shaft damper manitous use two way pistons which handle the rebound forces of coil springs and preload better than the one way pistons and are more tunable.

Once the lowers are off loosen the 24mm damper endcap and take the left staunchion out of the crown.
Unscrew the endcap, see how much oil you've got left. The through shaft damper needs a small air gap to buffer the pressure changes which occur in use, 10-15mm down from the end is where most seems happy, about the bottom of the threads.
Pour out the old oil and stroke the damper a few times to get the last out.

The lower seal in the endcap is the only critical one and can be replaced with a TPC style endcap and seal with better spring tensioned seals.
Excessive weeping or leaking like the type that'll leave a ring of oil every stroke is too much and must be dealt with.
The top seal isn't critical, any oil which escapes that way is returned by gravity and the forks action.

Push the damper shaft right down before you refill it with oil, sometimes it can come unseated when stroking out the old oil. A symptom of this is a clunk on bottomout before full travel is reached.
Fill the damper with oil to the bottom of the threads and stroke the air out. Repeat until most of the air bubbles are gone.
Refilling the damper totally and bleeding all the air is pointless. The through shaft dampers need a small air gap to buffer heat and pressure changes, leaving no gap will only increase the initial amount of weeping.

Reinstall the endcap, snug it up, not too tight and reassemble the fork.

 

[macker434172]

bike put back together

Dougal, I just wanted to thank you and everyone else for all the help. I took the shock apart and cleaned it all up and put it back together. It is working great so far. Everyone else had told me that it wasn't salvageable. Apparently they were wrong. I can tell a huge difference now riding on the trail. Thanks again, Ryan

 

[Dougal]

Happy to help.