[thaflyinfatman]

Just wondering if anyone (most likely Vitox) knew what kind of shaft sealing the Roco runs? Is it just an o-ring?

Also, how hard is it to get at the piston shims? Can they be swapped out without needing special tools or what?

 

[vitox]

yup yup it has an oil seal, the part description is "ANEL.TEN.12,7 MA25 N66803 DICH" for whatever thats worth.
to get to the shims you wont need any special tools, except for a sharp clip tool, for the ones in the compression valve you will need some pointy tool also to get an oring out is what i can remember offhand. be prepared to see some fancy machining and LOTS of shims. lemme know if you need any more info.

 

[thaflyinfatman]

Cheers mate - so it has a proper pressure seal on the shaft, not just an o-ring like Manitou and 5th run?

 

[vitox]

check what i found

i had lost the pictures i snapped when i went exploring for the first time inside a roco, but found em just now, maybe someone will find them interesting?

and to tffman, yep proper pressure seal.

 

[Arena_Swe]

Nice picture. .. i'll save that for future references .. U have any more photos of the disassembly?

 

[thaflyinfatman]

Ah sick, you're a legend Vitox! Thanks heaps.

 

[toodles]

Talk about resurrecting the dead but what the hell...

Has anyone used an off-the-shelf hydraulic seal to replace the shaft seal? My Roco is starting to leak and I'm not confident the Australia Marzocchi distributor will sell the shaft seals. Actually, I'm not even confident they will know what a shaft seal is.

 

[dhkid]

they are off the shelf hydraulic seals. give your local seal and bearing shop a call, just tell the them number of the seal you need.

 

[toodles]

they are off the shelf hydraulic seals. give your local seal and bearing shop a call, just tell the them number of the seal you need.

Cheers.. that is what I was hoping.

 

[davep]

If you have not seen it yet, there is a rebuild 'how to' here:
http://www.windwave.co.uk/documents/techinfo/rearshocks.html

There are also exploded shock diagrams showing all parts.......unfortuantely as this IS marzocchi, they do not give any actual part #s or specs for the parts. Only part 1, part 2, etc.

Idiots.

 

[toodles]

Yeah they're halfway helpful, but some details/info would be nice. It's a handy guide however.

*edit* for future reference the seal is a NAK UNP 12.7 x 19.05 x 3.96 MA25
The dust wiper is a NAK 12.7 x 18 x 3 - 4.5

 

[jamesdc]

Does anyone know of any online distributor that I could order a couple of the main roco oil seals from? I cant seem to find them anywhere.

 

[davep]

I cannot find anything when searching for those numbers as provided, but NAK is a Euro seal mfg, the numbers are the ID OD and thickness, 'UNP' refers to a cup seal type, but 'MA25' i dont know, maybe a material spec...

Anyway, I am sure if you pulled them out and took them to a seal suppler they could match them. I have alwasy been able to match seals like this here locally in Seattle...

 

[rewster]

check this site...they have exploded diagrams of the roco, and basic rebuild/bleeding instructions http://http://www.windwave.co.uk/documents/techinfo/rearshocks.html

the diagrams are not to scale (as far as the shims).....what are you trying to acheive? i run a roco on my sunday, which i had to totally retune for the leverage ratio. twas overdamped on compression and rebound sides badly. all you need is a 6 pack, bowl pack, and a dremel.

 

[rewster]

sry for multiple link...just saw davep's post above.

oh, and btw, don't bother calling marz........they haven't a damned clue what they're talking about. i called to ask a simple question, and the only answer they offered was "send it to us and we'll tune it for 125 bucks". finally pm'd marzocchitech on mtbr, who was actually pretty helpful.

if you're planning on messing with shims, the only thing to consider is maintaining the overall heigh of the entire stack. you can reduce shims or remove them....if you remove one, be sure to put a washer elsewhere in the stack to account for it's thickness. i took some old shims out of a 5th and dremeled them down to washer status. hope this helps

 

[miuan]

I rebuilt my Roco yday. Other than the rebound being too slow (removed one of the 3 HSR shims and put a bit thinner LSR shim), I set the IPF depth to 35mm (was 40mm) to better suit the shock to my Izimu. Big thanks to the monkeys for explanation of how stuff works, plus to Windwave for accurate and complete instructions (though they forgot to mention that oil must be spilt out prior to disassembly).

I couldn't however get to disassemble the HSC stack. The black nut holding the shims just wouldn't come loose. Actually there wasn't much I could do to keep the whole assy from turning, it just slipped in my hands as I tried to undo the nut. I did try to insert a 1.0mm and 1.5mm allen keys through the bleeding holes below the coil sprung shim to help hold the assy, but it just couldn't come loose anyway while the 1.0mm actually bent a little under the torque. I don't plan to mess with the shock again for at least a year or so, but for future reference and for others, can anyone advise how to tune the HSC shims? I recall Push make their own stack for Roco, so the whole thing may be sealed just like 888 carts.

 

[davep]

I assume you are talking about the shim stack on the main piston??

You need to clamp the shock shaft in proper vice jaws. Something like this: http://www.universalcycles.com/shopping/product_details.php?id=8555&category=746 with the correct sized holes to clamp the shaft in a vice without crushing/damaging the shaft. You can make you own out of some wood/drill/saw.

 

[miuan]

Nope, the HSC piston is located in the piggy.

The Main piston bolt was no problem to undo, I could easily reshim both HSR and LSC. I just find the HSC shims (in the pic) are too heavy for my weight, bike and ride style. What I'm trying to achieve is undo the nut on the left. Any suggestions??

 

[Marzocchi USA]

I rebuilt my Roco yday. Other than the rebound being too slow (removed one of the 3 HSR shims and put a bit thinner LSR shim), I set the IPF depth to 35mm (was 40mm) to better suit the shock to my Izimu. Big thanks to the monkeys for explanation of how stuff works, plus to Windwave for accurate and complete instructions (though they forgot to mention that oil must be spilt out prior to disassembly).

I couldn't however get to disassemble the HSC stack. The black nut holding the shims just wouldn't come loose. Actually there wasn't much I could do to keep the whole assy from turning, it just slipped in my hands as I tried to undo the nut. I did try to insert a 1.0mm and 1.5mm allen keys through the bleeding holes below the coil sprung shim to help hold the assy, but it just couldn't come loose anyway while the 1.0mm actually bent a little under the torque. I don't plan to mess with the shock again for at least a year or so, but for future reference and for others, can anyone advise how to tune the HSC shims? I recall Push make their own stack for Roco, so the whole thing may be sealed just like 888 carts.

Ciao!
You need a 1/2" shaft soft jaw to hold the body of the HSCV assembly. We actually have them available at Marzocchi USA, Part # R5171.
There is lock-tite on the nut to keep it from coming apart. You might even need to heat the part up a little to loosen up the bond. Careful not to melt the o-rings when you do that.

Cheers,
Marzocchi USA

 

[miuan]

Thanks Tom, wonderful that you registered at RM just to give me a reply! guess it's been beneficial for all
so if I understood right, I should clamp the 2 flat areas near the o-ring with a 1/2" jaw, possibly with the o-ring removed...

 

[Marzocchi USA]

Thanks Tom, wonderful that you registered at RM just to give me a reply! guess it's been beneficial for all
so if I understood right, I should clamp the 2 flat areas near the o-ring with a 1/2" jaw, possibly with the o-ring removed...

That's the spot. You don't even need to remove the o-ring. Make sure you don't damage that area though. If that o-ring or either side is damged the shock could leak.
Before they didn't put any loc-tite on the nut and it was a bit easier to remove but now they aren't taking ay chances with anything coming apart, as it should be!

If you are doing a lighter setting, a good way to go is to remove one of each size shim. Right now stock is;
2 - 22's
2 - 20's
2 - 19's
1 - 17
1 - 15

A good light setting is just 1 of each shim. That's what we use for bikes like an Iron Horse Sunday. It is also good for any coil shock that has a 350# or lighter spring. Less spring force equals less damping needed.

You would want to do the same thing with the main piston, just go with one of each shim on compression and remove one shim from the rebound.

Cheers!

 

[Transcend]

So...Chris or Ronnie? TR?

 

[William42]

So...Chris or Ronnie?

Tom, I think

 

[Transcend]

Tom, I think

It's one of the 3! Although last time I was at the office, I saw ronnie lookin' at the monkey.

 

[Marzocchi USA]

It's one of the 3! Although last time I was at the office, I saw ronnie lookin' at the monkey.

It's TR. Ronnie is too scared, and too busy with our website to post here. I'm not scared though. Peace!