[WeylessXPRider]

2004 Marzocchi Bomber Z.1 FR SL fork oil change

I'm currently working on getting the oil in my fork replaced, since I've had it for over a year, I think it's a good time to get the oil changed. What affect will this have on the fork? Since I'm going with a a 10 weight oil instead of the stock 7.5, what does that do for me? Should the fork feel a lot better after the oil replacement? Thanks in advanced.

Also does anybody else but me use a Z.1 FR SL like mine for anything else but trail riding?, I've used mine for, trails, dirt jumping, and downhilling.

 

[fsrxc]

I'm currently working on getting the oil in my fork replaced, since I've had it for over a year, I think it's a good time to get the oil changed. What affect will this have on the fork? Since I'm going with a a 10 weight oil instead of the stock 7.5, what does that do for me? Should the fork feel a lot better after the oil replacement? Thanks in advanced.

Also does anybody else but me use a Z.1 FR SL like mine for anything else but trail riding?, I've used mine for, trails, dirt jumping, and downhilling.

better how? If you are heavy and find the damping currently is too fast (and/or out of range of the rebound adjuster), then yes, it might help.

 

[WeylessXPRider]

The fork has Doppio Air, so it really doesn't have a Rebound adjustment at all, all it has is ECC which adjust rebound and travel.

I current weigh around 185, with no gear, and around 190 to 195 with gear. I'm also hoping this will also help with the very light thud that I feel through the handle bars when I pull sharply on the handle bars, when it extends to full travel really quickly.

 

[chad1433]

Weight is not a good indicator of oil viscosity. Check here:

http://www.peterverdonedesigns.com/bikesuspension.htm

That top out can be tuned out by adding a bit of negative air pressure.

 

[Mr.Whitney]

you should decrease the positive air a tiny amount. that will eliminate the thud.

 

[WeylessXPRider]

I think changing the oil weight was the right decision, lowering the pos air would make me use more travel and sag a lot more which I do not want, I'm also have added a lot of negative air pressure already.

 

[WeylessXPRider]

Air pressure in the leg with ECC

Does anyone know the stock air pressure for the leg with the ECC nob, found out there's a valve that under the nob which needs to be filled with air, but since I got my fork oil changed, the air had to be let out, anybody know the stock air pressure?

 

[WeylessXPRider]

Just looked something up, is that the air assist preload?

 

[rsbaker63]

The ECC side should have about the same air pressure as the other side. Both sides work as positive springs to hold up your weight. For the top out try using higher pressure on the negative side. This side is really a small chamber the pressure changes very quickly as the fork moves but it provides for a cusion at the top of the stroke.

 

[WeylessXPRider]

The ECC side should have about the same air pressure as the other side. Both sides work as positive springs to hold up your weight. For the top out try using higher pressure on the negative side. This side is really a small chamber the pressure changes very quickly as the fork moves but it provides for a cusion at the top of the stroke.

What's the recommend air pressure for the neg air spring, I've heard that you should use around 3 times as much pressure as the pos air spring.

 

[chad1433]

I weigh about 190 w/gear. If I recall correctly, I was using 35psi Pos pressure in each leg and 100psi negative pressure. Start there, see how it feels.

Adding negative air pressure is the way to prevent top out because it brings more of the stanchion into the lowers and resists those upward forces. The thing with the Doppio Air is that it's very sensitive to small incremental changes, so if you can, find yourself a pump with only a 200psi dial. That'll help you know exactly how much pressure you have in there. It's very easy to get the settings into a state of chaos.:madman:

 

[jp3d]

I weigh about 190 w/gear. If I recall correctly, I was using 35psi Pos pressure in each leg and 100psi negative pressure. Start there, see how it feels.

Adding negative air pressure is the way to prevent top out because it brings more of the stanchion into the lowers and resists those upward forces. The thing with the Doppio Air is that it's very sensitive to small incremental changes, so if you can, find yourself a pump with only a 200psi dial. That'll help you know exactly how much pressure you have in there. It's very easy to get the settings into a state of chaos.:madman:

I find it helps to write down different pressure combinations you try, and then note how they feel, otherwise you will get confused. You definately need more negative pressure. Try simply setting the sag by adding equal pressure to the two positive chambers. Then add air to the negative chamber until you don't get any more top-out clunk. Also note that the negative chamber is so small that each time you attach the pump, much of the air for the negative chamber goes into filling up the pump hose, so write down those negative settings in particular!

 

[WeylessXPRider]

Well I've got a marzocchi made pump with the adapter, has 200 psi range too, so I'm set in that range. It seems that I'm going to have to use a low psi the what it suggest, not to sure, since I read the article on oil weights and viscosity. I'm currently using:

Wako's 10 wt fork oil

Not sure if that's about the same or if it runs more viscous than the Marzocchi Factory Fork oil 7.5 wt. Anybody got any ideas about it, I think it's made in Japan, so I don't know where to get the info.