Marzocchi 48mm CC Forks

[wence]

Just an update,
Spoke to the suspension people that did my forks today and they were very helpful.
The spacer / washer is located at the point where the dampener rod enters the inner cartridge and is meant to be there and meant to be loose as it slides down into a sleeve internally once installed in the outer fork leg.

The reason for only 230-250ml of oil being in the outer tubes is basically because the max they would have put in would be 270 ml depending on what the forks had in them when they opened them up??? I did push this a little further but for some unknown reason they don't put enough oil in there.

The lack of oil caused the clunk and cavitation in my forks and also caused them to have no bottoming resistance.

Not sure why one leg has 16 turns of compression adjustment and the other 24 or why the PFP spring flopped around in one leg and not the other. They said they should both be equal,( obviously they were not).

Hmmmmm

 

[Simmo737]

I reckon that sounds like they just did em like a kyb aoss and assumed its the same. Was that a local bloke or interstate?

 

[wence]

Interstate for me.
I'll PM you if you need to know as I don't want to bag people on here.
Cheers Mark

 

[Simmo737]

yep, i was being discrete as well. cheers

 

[Vindicator]

Just an update,
Not sure why one leg has 16 turns of compression adjustment and the other 24 or why the PFP spring flopped around in one leg and not the other. They said they should both be equal,( obviously they were not).

Hmmmmm

It's because the PFP shaft is not mounted correctly. You need to unscrew it to bring it up a bit. I have detailed pictures on how you can do this, tomorrow will post it as I have finished a complete service on the compression unit .
In any case take a look at the picture below that shows where you can adjust the PFP shaft , you need to unscrew the shaft where the arrows point to :

You need to use the 22 to hold the PFP adjuster on the top and a 14(?) where the arrow is pointing. Backup the compression adjustment rod all the way out and LEAVE THE AIR SCREW ON the PFP adjuster before using the 22 .
If you backup the top of the shaft a little you will gain more compression clicks

 

[wence]

It's because the PFP shaft is not mounted correctly. You need to unscrew it to bring it up a bit. I have detailed pictures on how you can do this, tomorrow will post it as I have finished a complete service on the compression unit .
In any case take a look at the picture below that shows where you can adjust the PFP shaft , you need to unscrew the shaft where the arrows point to :

You need to use the 22 to hold the PFP adjuster on the top and a 14(?) where the arrow is pointing. Backup the compression adjustment rod all the way out and LEAVE THE AIR SCREW ON the PFP adjuster before using the 22 .
If you backup the top of the shaft a little you will gain more compression clicks

Thanks mate,
The PFP spring was really loose so I did do it up a touch.In hindsight it probably was not such a good idea.
On the bright side , I am learning and the forks are now working properly.
I will get back in there soon and change the oil as I want all clean good stuff for this years races.
Cheers Mark

 

[Jakobi]

Was going to suggest the same thing re different numbers of clicks. I'm sure I read a similar post on another site re a set of showas.

Good work Mark. When I do mine I'll use the vac pump to pull as much air from the oil itself before even starting to fill the carts. The rest seems easiest enough (as per the manual), with the trick being the fast compressions at the end. What weight oil did you end up going with?

 

[wence]

I ended up putting in 340ml mate.
One good thing the tuner said re the fast pumping at the end was to gently do the first one or two to expel most of the air and then go for it otherwise air and oil will be mixed ( oil aerated), not sure how true this is but sounded feasible.
Cheers Mark

 

[Vindicator]

It was time to work on the forks again, my arms were telling me so .
First thing I noticed when draining the oil was the highly contaminated outer oil after sitting for 1 week:

The cartridge oil was just about the same:

This observation and the fact that one of the cartridges would not fully compress, even though I had bleed it correctly when setting it up the last time, really puzzles me . After a quick stroke of the damping rod, I could hear oil bursting through the compression shaft recess and full travel of the damping rod was achieved . The damping rod of the 2nd cartridge had full travel but when I tipped it over, oil came out the 2 draining holes on the top . I'm 100% sure I didn't left it there on previous assembly .
The quantity of outer oil drained was more or less the same amount it was filled, the rest was all over the floor

I don't understand how the oil could get such level of debris after only ~30 hours of riding. Could it be just from the bushings ?

 

[Vindicator]

Here's a pic of the PFP/compression unit dismantled:

Did not dismantled the PFP piston, didn't appeal to my curiosity

Picture of the PFP adjuster that also holds the small steel ball and spring that are responsible for the compression clicks. As you can see they are full of grease and I could barely hear/feel the clicks. I cleaned everything and applied a good quantity of Motorex's Joker and the result was quite good, clicks are now evident

 

[wence]

Good write up mate.
How do they feel now?
Cheers Mark

 

[Vindicator]

Had no time yet nor decent weather

 

[Vindicator]

Removed the compression piston and cleaned all the shims:

Backup the compression rod all the way out before removing the PFP adjuster. Used the 22 to hold the PFP shaft on the top and a 14(?) to unscrew it from lower part of the shaft

Compression rod adjuster

 

[Vindicator]

Cartridge/PFP cap :

That circlip on the shaft is what stops the PFP inner top cap from compressing the spring any further. Not a good idea to force the PFP once it reached the maximum of its adjustment .

Remove the circlip and use the octagonal cap tool to hold it and with a wrench on the PFP shaft unscrew it until the inner PFP cap threads are all out

As you can see there is another circlip at the bottom. This one is responsible for holding the PFP adjuster from moving on the cartridge cap . It's very important to have this circlip set straight, besides holding the PFP adjuster it also stops the steel ball and spring from the compression clickers from falling and sets tension on the spring:

Beneath the circlip there's a steel washer, once removed you just need to push up the PFP adjuster :

I did not use any strong grease when putting it back together because this is all fitted with small tolerances and the grease just makes it very hard to adjust all the parts including the compression clickers. Instead I sprayed everything with Motorex's Joker .

 

[Vindicator]

The bushings on the PFP piston are done:

Is there a crossover for this ? I'm having a though time getting it from Marzocchi

 

[Vindicator]

Word of advice:

Whatever you do, do not over-tighten the PFP shaft ! It holds a circlip on the threads that is supposed to act has a stopper when tightening both halves, the threads are very fragile. In theory, when done properly, this should give you the 26 clicks on the compression adjuster, if not, you need to adjust :

I think the engineers at Marzocchi could have come up with a less prone to mistake/damage solution than this...

 

[noobi]

Would it be appropriate to consider the PFP spring to be similar to a top out spring?

 

[Jakobi]

Would it be appropriate to consider the PFP spring to be similar to a top out spring?

Not really noobi.

The PFP is Marzocchis equivalent to Yamaha and Showas ICS Spring, or WP/Ohlins N2 Charge (bladder/piston).

The internal chamber basically follows the same principals as a shocky, using pressure to reduce cavitation. A shock uses a resevoir and nitrogen (either via a bladder or piston). The PFP does the same to thing to the cartridge. Now think of a shock running very low pressure, and then one running a higher pressure. What the PFP does is allow an external adjustment for the fork.

 

[noobi]

Not really noobi.

I thought that too, but it came up in conversation whilst servicing some YZ125 forks.

 

[Motorockr]

Hi everyone, I'm new to the marzocchi cc fork. I have a question. I was messing with my compression clickers to get a feel for adjustment and I realized that my left fork has 27 clicks and my right only has 21. I have done tons of research on this to no avail. Am I overlooking something simple? I am decent with suspension but I am definitely no expert. Any help would be gratefully accepted!!