Marz Fork oil change & setting AIR GAP!

[Guest ratchethack]

It's a little different from my experience with the same springs, Ryan.

 

The fully-illustrated instructions that come with Wilbers springs #600-062-01 are helpful, and they guide you through a complete oil change - but they're in German. So Wilbers USA provides a 9-point, one-page supplement. Between the 2, the instructions are pretty good.

 

Nowhere is there anything about a spec for fluid or air gap by rider weight. 'Course you can always vary both of 'em to fine tune the fork. . . . . IMHO, you'd only be inclined to go with higher-viscosity oil and less air gap with higher rate springs for greater loads - but that's just me.

 

The Wilbers recommended viscosity is SAE 7.5 wt. I've tried 10 wt and 7.5 wt, but prefer synthetic CARTRIDGE FORK FLUID, 125/150.

 

The recommended air gap (Luftkammer) is 100 mm.

 

EDIT: Strangely enough, the insert from Wilbers USA has what I have to conclude is a significant misprint. It calls for a huge air gap of 300 mm!

 

Here's my reasoning on the "real" air gap being 100 mm:

 

1. The German instructions and the label on the box both specify 100 mm Luftkammer.

 

2. The hand-written spec by the US Rep on separate paper is 100 mm.

 

3. If you actually used 300 mm, I guess this would amount to only about 100 cc of oil in each fork leg, which is a whopping 300 cc less than the Guzzi manual calls for.

 

4. 100 mm air gap works out perfectly for me at my riding weight. Any change of as little as 10 mm, and it would be obviously too much air spring or too little, depending........

[kanoa]

i just did my forks last night and swapped out the stock springs for a set of Wilbers with a 100mm air-gap above a 50/50 mix of redline 5wt and redline 10wt suspension fluid. this how-to was a great help, thank you.

 

since i was at 3500 miles i chose to take the easy route and pass on the full-rebuild (as suggested) and i did a lot of the work with the forks in the triple clamps. i did waste an hour trying to figure out how in the hell to compress the springs far enough to get the blue jam nuts back on and then realized all you need to do is lift the threaded bit (cartridge) in the fork tube.

 

thanks again this forum is awesome

[Distilled Waters Run Deep]

Does anyone know if 100mm air gap applies to other 'zocchi forks?

-I've finally got around to changing fork oil - non-adjustable dampers- on my 2000 Jackal- it's done about 25000 & I can see the signs of someone doing them previously, by marks on the caps of the bottom bolts which hold the plungers into the legs (marked MA23 936).

I swished & pumped around some very old stinky petrol & flushed with brake cleaner, got some silvery dust out & rinsed til fairly clear. Other than that, not much sign of wear and seals are good.

The manual says to replace .560 litres, which is more than I got out of them.

[tricatcent]

Is there any way that, while the forks are apart, a hole could be drilled and tapped for a plug near the bottom of each leg, so that the next time it is time to change the fork oil, all you have to do is take out the plug and pump the forks up and down a few times.

 

That is the way all motorcycles used to work. Changing the fork oil was about a half hour job.

 

Or is there a way to suck the oil out from the top?

 

Nigel

[Distilled Waters Run Deep]

Is there any way that, while the forks are apart, a hole could be drilled and tapped for a plug near the bottom of each leg, so that the next time it is time to change the fork oil, all you have to do is take out the plug and pump the forks up and down a few times

 

That's how they come, on Calis -screws with 'o' rings. I did what you suggest to a pair of Honda forks I fitted to my V50 once -you have to be good with your tap though, or you'll have leaky legs -and like me end up taking them out to 8mm plugs!

Please note my level of expertise before taking any of my 'advice'

Sucking the oil out through the top with a pump like this should work, though if you've read what comes before on this thread you'll want to flush them to get rid of the swarf.

 

Anyway, whaddya know about oil height?