Marzocchi M1BB fork curiosity

discussion about the 750 Sport and '89/'90 900SS, which share many mechanicals with the Paso series
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Kiwi Rider
Posts: 50
Joined: Thu Sep 05, 2024 6:47 am
model: 750 Sport
year: 1988
Location: Southland, New Zealand

Marzocchi M1BB fork curiosity

Post by Kiwi Rider »

I pulled my forks apart today to change the oil and fit new seals. I discovered there is a cylindrical weight fitted inside the bottom of the fork stanchions held in place by an internal circlip. (Item on the left in the photo)
I've never seen this in a fork design before. Anyone know what its purpose is? The racer in me wants to throw it away to lighten the forks up a bit :lol:
I'm going to use 10W oil and will try the airgap of 150mm as spec'd in the workshop manual. It's not hard to add more oil at the track if I need. Feel free to offer any opinions on this.
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Mc tool
paso grand pooh-bah
Posts: 1984
Joined: Wed Dec 05, 2007 12:35 am
model: 906 Paso
year: 1990
Location: Riverton New Zealand

Re: Marzocchi M1BB fork curiosity

Post by Mc tool »

I think that sleeve is part of a cushion dampner that comes in to effect just before the fork bottoms out . Maybe the lower part of the dampener tube just fits inside it ?
I wish I was young again............Id be heaps smarter than last time
Kiwi Rider
Posts: 50
Joined: Thu Sep 05, 2024 6:47 am
model: 750 Sport
year: 1988
Location: Southland, New Zealand

Re: Marzocchi M1BB fork curiosity

Post by Kiwi Rider »

With thought, I think it provides the correct length for the top out spring underneath the damper rod piston head to hit against at full extension. Yes the damper rod slides inside the ID. I've decided to keep it!
Mc tool
paso grand pooh-bah
Posts: 1984
Joined: Wed Dec 05, 2007 12:35 am
model: 906 Paso
year: 1990
Location: Riverton New Zealand

Re: Marzocchi M1BB fork curiosity

Post by Mc tool »

Ooooh , I think it could stand a wee wizz on the lathe :evil: :lol: :lol:
I wish I was young again............Id be heaps smarter than last time
Kiwi Rider
Posts: 50
Joined: Thu Sep 05, 2024 6:47 am
model: 750 Sport
year: 1988
Location: Southland, New Zealand

Re: Marzocchi M1BB fork curiosity

Post by Kiwi Rider »

Mc tool wrote: Fri Jan 17, 2025 12:05 am Ooooh , I think it could stand a wee wizz on the lathe :evil: :lol: :lol:
It's either that or attack it with the battery drill and give it the swiss cheese look! :mrgreen:
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