Marzocchi Fork Seals, 1 or 2 seals?

[Steve G.]

Redoing my seals and generally cleaning things everywhere. Parts and technical friend Wolfgang Haerter has confirmed 2 seals are not needed, just one.
What’s the consensus out there in the Laverda Family?

 

[martymoose]

One seal with a spacer, to stop it moving. The spacer can be an old seal, with the inside cut out.

 

[Steve G.]

That’s what I was thinking, to leave the lower down seal in place, to prevent a single seal
“Walking” up, down, or banked sideways.

 

[psg]

That’s what I was thinking, to leave the lower down seal in place, to prevent a single seal
“Walking” up, down, or banked sideways.

Somewhere about 25+ years ago I found the correct size pair of twin lip seals, like you're thinking, just took out the top seal, left in the bottom ones. put in the new ones on top. Still dry as a bone and no stiction issues.

 

[henrywillms]

One seal, no spacer, never moved, never leaked. In past used a spacer but found not needed.

 

[Haggis]

1 seal and a spacer for me. For many miles with no issues.
If going into the 'generic seal' shop, get linear rather than rotary seals (i.e. the type for hydraulic rams etc, rather than spinny stuff) you will then get the correct lip layout.

 

[Steve G.]

Actually, it looks like Wolfgang sent me a much more substantial and much deeper double lip seal , than the twin very thin double seals. I’ve installed one already, quite happy with the firm installation. Actually, much caution was given that very minimal “prying “ should be avoided. I decided to take it to my favourite vintage/classic motorcycle shop locally (Shail’s Motorcycles), where they used a nicely set up slide hammer with a hook to safely remove the seals, and used a perfected seal tap to tap the new one in. I shal rebuild it now, very happy so far.

Now I shall have to make the decision on fork oil viscosity!!! Opening up a can of worms I’m sure!!

 

[The Sock]

Now I shall have to make the decision on fork oil viscosity!!! Opening up a can of worms I’m sure!!

Oh! goody, an oil thread!
That'll produce an instant consensus.

 

[Steve G.]

Well, I’m a big guy, 260ib, so thinking of going up to 15w fork oil

 

[Haggis]

Hi Steve
If you want to perfect your fork oil choice then making sure your static and rider sag are correct is absolutely essential. Once the springs are right, the suitable oil becomes very easy. Otherwise there might be a lot of tail chasing

 

[Steve G.]

Good info!!!

 

[Ian Short]

Well, I’m a big guy, 260ib, so thinking of going up to 15w fork oil

Once your spring rate is correct the oil viscosity plays a fairly minor role, 10W vs 15W, you're not likely to notice a difference. Unless you have done signifcant valving changes and have exceptional feel....... Perhaps your real name is Steve Crevier .

 

[Steve G.]

Once your spring rate is correct the oil viscosity plays a fairly minor role, 10W vs 15W, you're not likely to notice a difference. Unless you have done signifcant valving changes and have exceptional feel....... Perhaps your real name is Steve Crevier .

Well, I do live around 5 miles away from Steve Crevier, but barely 7.5% of his skill. Actually here’s a picture of Steve sitting on my Norton last summer!

 

[Tippie]

1. Springs to suit your weight, measured with sag.
2. Oil to suit the springs.
Too light springs and heavy oil is not the way to go.