Marzocchi Dampener Rod Length & different internals

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MartinMille BANNED
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Marzocchi Dampener Rod Length & different internals

Post by MartinMille BANNED »

Hi All
I took the SS forks apart ready for paint and overhaul, when I noticed that the rod dampeners where 20mm longer when compared to SD forks
The SS uses a tube length of 580mm while the SD uses 600mm , both fork legs are the same high and both forks when reassembled are also the same high

Here is my question for Steve (US) or Dave
As both forks take roughly the same amount of fluid, would the longer rod of the SS have better dampening as more fluid would have to pass through it at each up or down damping stroke ???
Or is the internal valving different eg; more or less bleed ?

There are also a few differences with the rod valving as well
the SS rod has its scraper ring towards the top and on the later versions this is lower, all they have done is reversed the piston , next to the rod spring on the SS it is more of a cone shape when compared to the other that is now your normal type spring , the SS spring is much heavier and also has one extra washer,the rod length it self is longer on the SS and the lower retaining locking block is steel in the SS and aluminum in the other

The thing that I noticed straight away was the piston, on the SS the piston would expose the top side rod holes this was not the case with the other rod where the piston was inverted thus covering the hole

Here are some comparison pictures

This first picture shows the different rod length , the longer one is and SS rod
Note the relation of holes between each rod and the position of the piston ring

Image


The pic shows the parts that each rod contains note the progressive spring in the SS rod

Image

This last pictures shows the modded rod that I have made using parts from both rods , SD rod with SS spring and base locking block from an SD, has enabled me to use a 600mm SD tube, that I have 4 brand new tubes of anyway by doing so all the rod holes are now lined up allowing be to use 600mm tubes, from the outside both re-assembled fork legs look identical

the top rod is SS rod
the middle is the SD/SS modded rod
the last is std SD rod

Image

I may yet remove my listing on the rod dampeners so that I can do this ,why spend $$$ when I have all the parts for the job , hard chroming my original 580mm tubes @$150 each is the other option modding the rod cost to me is Zero

Comments anyone ???

Cheers
MartinMille BANNED
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Post by MartinMille BANNED »

Pictures now added
Aussiess
Parallel Twin
Posts: 144
Joined: Sun Oct 31, 2004 6:51 pm
Location: Blue mtns, NSW, OZ

Post by Aussiess »

Martin, this is very interesting, I will be interested a little more with the ride report on the action /dampening performance etc.

Theoretically I could only see provided the oil pathways are constant the performance coming back to the spring rates?
Regards,
Grant
79 900SS , 82 MHR and 78 NCR Replica
MartinMille BANNED
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Post by MartinMille BANNED »

'
The thing is Grant I wont be riding the bike til later in the year as I still have lots today before I'm anywhere near ready ,
I have to get the engine working with the new ignition system first (( Hi Dave :lol: )) and after that I will bolt everything on it and take her for a spin

BTW like my new plates ???

Can you believe that they were was still available


Image
Last edited by MartinMille BANNED on Tue Mar 31, 2009 9:03 pm, edited 1 time in total.
Aussiess
Parallel Twin
Posts: 144
Joined: Sun Oct 31, 2004 6:51 pm
Location: Blue mtns, NSW, OZ

Post by Aussiess »

Martin its amazing what you find when you look.
I own MHR 82 and NCR 78 and the SSD plate (on bikes now)! I was blown away they were available too.
Me thinks the secrets out now
Image
Regards,
Grant
79 900SS , 82 MHR and 78 NCR Replica
MartinMille BANNED
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Post by MartinMille BANNED »

SHHHHHHHHHHHHHHH

Image
Aussiess
Parallel Twin
Posts: 144
Joined: Sun Oct 31, 2004 6:51 pm
Location: Blue mtns, NSW, OZ

Post by Aussiess »

Very cool
Regards,
Grant
79 900SS , 82 MHR and 78 NCR Replica
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