Stock shim stacks for the Marzocchi Shiver 48 on 4Ts

[Leon_RR250]

Hi!

I did finally test the PFP with half turn in on preload and started with 6 clicks out on comp. I went out until 9 clicks but it was really active with some jarring to the hands. So I ended the practice with 6 clicks out on comp which was generally ok. Not much time to try stiffer on the comp clickers. Anyway, the previous setting was more consistent at 1 turn in for PFP preload, 12 out on comp and 9 out on reb.

Leon

[celler]

Are you back to the stock shim stack or do you have the bleed shims removed?

[Leon_RR250]

Hi!

If you check earlier posts you will see that I am on almost stock stacks except some thinner base shims and a bit less float on the mid.

Leon

[GOT2MOTO]

Leon,

I've been reading through your post. I just bought a 2014 350RR Factory Race Edition Beta with the same forks you have detailed in this thread. With about 12 hours on the bike now I decided it was time to service the suspension. I took the 48mm Marzocchis apart and did a thorough inspection. None of the problems that GMP has experienced. My internals looked as if new and no aluminum bits or anodize was rubbed off. I removed the base valve and measured all the Comp. shims. I found my stock base valve stack to be identical to yours. The only diffence was the (3) 30 x .15 that you substituted with the (8) 30 x .10. This valving was very similar to what I found in my 2008 45mm Zoke shivers. I was shocked to see such light valving because when I ride my bike it feels harsh everywhere until you get going and speed and hit things. The bike does weird stuff up front in the small rock and roots but takes square edge very well. I left the base valve as is, but was curious if you think changing just the Mid Valve float is all this fork needs to get rid of the mid stroke spike I encounter? I currently have the .48 springs set at 5mm preload, PFP at 2 turns in, comp. clickers at 18 out and rebound clickers at 16 out. Using Spectro 125/150 7.5 wt oil 26.1 at 40C, as was stock.

Curtis

[GMP]

Valving is light on paper because cartridge pressure is high. You can stack face shims like a deck of cards on a KYB with softer ICS and its a lot softer than a Zoke 48. What you may be feeling is a high speed rebound spike, not a compression spike. Remove the bleed on the mid and rebound and try it. PFP at 2 turns in is a bit stiff for general woods at least on my 300. These forks have a firm, confident feel about them. Not what I'd call plush but no bad habits either.

[celler]

Leon,

I've been reading through your post. I just bought a 2014 350RR Factory Race Edition Beta with the same forks you have detailed in this thread. With about 12 hours on the bike now I decided it was time to service the suspension. I took the 48mm Marzocchis apart and did a thorough inspection. None of the problems that GMP has experienced. My internals looked as if new and no aluminum bits or anodize was rubbed off. I removed the base valve and measured all the Comp. shims. I found my stock base valve stack to be identical to yours. The only diffence was the (3) 30 x .15 that you substituted with the (8) 30 x .10. This valving was very similar to what I found in my 2008 45mm Zoke shivers. I was shocked to see such light valving because when I ride my bike it feels harsh everywhere until you get going and speed and hit things. The bike does weird stuff up front in the small rock and roots but takes square edge very well. I left the base valve as is, but was curious if you think changing just the Mid Valve float is all this fork needs to get rid of the mid stroke spike I encounter? I currently have the .48 springs set at 5mm preload, PFP at 2 turns in, comp. clickers at 18 out and rebound clickers at 16 out. Using Spectro 125/150 7.5 wt oil 26.1 at 40C, as was stock.

Curtis

With the same exact oil, stock springs (.44), stock valve stacks, I'm running PFP 1 (2 is also Ok) c 10 and r 3 on a 250 rr. I would also say that I have properly bleed cartridges (Good write up on this at GG forum) The bike was busy until I slowed the rebound down. I run in a lot of small rocks in Missouri and it also worked well in Colorado.

[GOT2MOTO]

Valving is light on paper because cartridge pressure is high. You can stack face shims like a deck of cards on a KYB with softer ICS and its a lot softer than a Zoke 48. What you may be feeling is a high speed rebound spike, not a compression spike. Remove the bleed on the mid and rebound and try it. PFP at 2 turns in is a bit stiff for general woods at least on my 300. These forks have a firm, confident feel about them. Not what I'd call plush but no bad habits either.

Glen,

The forks are far from plush and do allow me to hit stuff at speed, I just want them to be just a little less busy in the rocks and roots. So once I have the damper rod out, the Mid Valve will have a rebound and compression stack that both have free bleed shims? That seems odd allowing oil to flow both ways with little resistance using shims. I am not use to this fork setup at all. I've worked on my sons KX450F KYB's for years and they are much more straight forward to tune. This free bleed shim stuff is a different animal for me. I'm use to the free bleed in the piston setup with different diameter holes that keep the free bleed fixed. Using shims would seem to make the free bleed vary and harder to tune. What will removing free bleed shims from the mid valve stacks give me? More rebound damping and compression damping only? More adjustment with the clickers?

Thanks,

Curtis

[dirtbird]

Curtis, before start shimming try less oil on the outer chamber and 1 turn in (from fully out) on the PFP.
Moreover, I think that the Spectro you've used is actually the same that Marzocchi uses from the factory.
If that's true, my personal op. is that this is clser to a liquid grease than to a fork oil.
I have tried Marzocchi oil and apart of its viscosity, one thing that I've noticed was how sticky it was.
I am using most of the time a RACE TECH's tube to measure oil quantity and with this thing I had always oil sticking to the bottom.
If I wanted to clean the tube, I had to leave it upside down for half an hour.

So -IMO- try also a different fork oil that you are familiar with and has a close viscosity.
Personally I am using NILS ForFork 7.5w (23cSt) but In the next oil service (or sooner) I will use NILS For Shock High (15.7cSt) which is 100% synthetic and I am using it on my shocks. What I have noticed with the latter is that when servicing and bleeding the shocks, I get no foaming at all (equals no cavitation=no loss of damping). If you combine that with a very brave and accurate observation that Glenn did recently* and see what happens. Truth is that in CC you don't get any foaming (or you get very little - difficult to access accurately) but still I want to try it.
NILS oils are not available in US but they are top quality (and also are tech sponsors of the factory Honda MX1 team).


*In other words, in the past with OC forks we always thought that we need some riding time to get the oil hot to start being plush, however the truth is closer to that while you are riding you get more and more bubbles and the inevitable loss of damping - no OC fork gets really hot.

[Leon_RR250]

Hi!

Now that I have changed the 400 to the new 350 EFI 2015 and having ridden the stock Sachs forks for 5 hours (and then the WP Cone Valve for the last 1,5 hours until I hit badly my right shoulder and starting to ride again next Saturday after a total of 4 weeks break), I have to say that my settings on the Marzocchi 48 were not as good as the 2015 Sachs in small sharp rocks and roots (especially when wet) with 2nd gear. It was better everywhere else but not there. It was kind of busy and almost deflecting but I got used to it somehow and my late results before changing the bike were actually good. Then I hit the jackpot with my latest compression revalve on the cone valve and I was really flying (for my standards) until I hit the wrong braking point on a long straight on rocky and wet surface falling badly. Good that the bike got only some scratches on the right plus a new grip waiting for the next ride.

Anyway, from my previous setting on the Marzocchi 48, I would continue by removing the bleed shim from the rebound stack and making the Mid float exactly the same as stock (as you have it now). And try to find the new clicker settings with PFP at 1 turn (it was still very good in soft sand, fast whoops, MX, ...) in or max at 1 and a half turn in. Oil in the outer chambers still the same as stock at 370 ml.

Leon

[GOT2MOTO]

Thanks for all your replies guys. At this point I think I'm going to try just the new amount of Spectro 125/150 oil at 370ml in each outer chamber with the 200ml @ 140mm in the inner chamber. I will put the PFP at 1 1/2 turns and give it a try in this weekends enduro. I ordered some Redline Full Synthetic 10wt and 5wt to mix at 2 to 1 ratio on the next tune. I almost bought Silkolene 7.5wt RSF but saw how high the viscosity was @ 40C and passed on it. The fork is easy to disassemble so I think I will have to try different things one at a time to see if I get some improvement. First change is oil amount in outer chamber and lighter PFP setting. I will post how it feels after Saturdays event. Thanks again.