Revalved Marzocchi Shiver 45 for plushness.

[JTT]

Originally Posted by GMP

lets the stack move more on a fast hit.

You sure about that Glenn? Seems to me that with the cross over you are effectively working with a single stack of
22x10
22x10
11x10
19x15
until the .1 is used up and the 19 comes into contact with the 17. Eliminating the crossover I would envision, would support the whole stack from the bottom up, making it effectively stiffer overall.

Take out the 13x20 and replace with a 11x20 or 10x20 and the whole lot gets softer.

[GMP]

Joe, your right. I got ahead of myself, thinking about my entire HS section being softer. It would be softer, then get stiff, but at what speed? More non-linear. I have to look at the stack in my brother's TE450 fork, that bike is similar in weight to the FSE and works very well in rocks.

[bergerhag]

This weekend I had the opportunity to ride an enduro on the same trails and special stages as one of the rounds of the Swedish Enduro Championship. I can tell you that the difficulty of this was quite a few levels above what I am used to. One of the specials was going up and down a ski slope. On the uphill parts the suspension worked nicely. BUT DOWNHILL!! Man, I felt like a submarine commander yelling "DIVE,DIVE" to my forks... Going hard on the front breaks on a steep ROCKY downhill section was not what my forks were setup to do. I had to go so slow that my springs could take the hits. On the enduro test, some parts were more trials like, and again I felt the forks bottoming on steep downhills. I was going quite slow on first gear.
So, a lot more low speed compression seems adequate. At the first lap I had the comp clickers on -12, went to -9 for the second, but it was still not enough.
Is there any chance that adjusting clickers tighter will do me any good on this, or is it revalving time again? Adding another 22x10 shim on top, will that effect high speed damping too?

[pobit]

bergerhag, fork diving is caused by soft fork springs or too much preload on the rear spring causing the back end to lift up when unloaded. This of course assumes you have the rebound clickers set properly front and rear. If you have more than 10mm of preload on the rear spring, it's going to be a problem. 6-8 is ideal. These zoke forks have an incredible amount of free bleed in them so the compression valving does not come into play until the fork compresses fast enough to open the valving. The adjuster screw on the base valve only controls when that valving starts to engage by increasing or reducing the free bleed. Most of the time you ride around on the springs, oil height and rebound dampening. The correct way to tune this fork is to first get the correct springs for your weight. If your fork springs are too soft, the air spring ramps up too fast and makes for a harsh ride. Make sure the new fork springs are set at 5mm of preload or your rebound won't work. The oil height needs to be at 125-130mm with the stock rebound dampening. If you run a higher oil height like 110mm this also causes the air spring to ramp up too fast causing a spike and also causing the fork to rebound too fast fooling you into thinking the fork is too stiff. Go back to the stock valving with the correct oil height and springs and try using the clickers to dial it in. Dave

[bergerhag]

Thanks Dave, that cleared things up a bit. So, as for springs selection, my current front sag is at ~30 mm, race sag at ~80mm. I haven't actually measured it, just a calculation. My race sag with stock 4,2N springs was 100mm, and with two 4,6N springs it was 65mm, so I guess now with one stock spring it would land in the middle of 100 and 65 mm, ~82mm. Am I all set here?

So, basically what you are saing Dave, assuming my sag is right, is that all my previous problems with spikes and bike deflecting off any kind of rocks, is all caused by high oil level?
Ok, I'll give your formula a go, Dave. It's fun to tear down forks!

[pobit]

What I am saying is you need springs stiff enough for your weight and the oil set at the correct level. How much do you weigh? That will determine what springs to use. The stock rebound stack is valved for the oil level to be between 125-130 mm with .42 springs. If your going to use stiffer springs and the stock rebound dampening, set the oil level lower to compensate. You can go as low as 140mm without problems. Dave

[bergerhag]

Thanks for taking the time, guys. I really want to learn this stuff.
I'm 230 lbs(105kg) in my skin. 255lbs(116kg) in full outfit.

I hadn't seen the connection between rebound and oil level, but now when you say it, it makes perfekt sense. (I think..)

[pobit]

Use both the .46's with 3-5mm of preload. Start with the oil level at 140mm with the stock valving and start with the rebound at 12 clicks out. You shouldn't have to go more than 3 clicks either way to get it right. Rebound is used for stability and compliance. Too tight and the bike will fall to the inside on turns and feel harsh on multiple hits. Too loose, the the bike will want to go over the berm in turns and have an unstable feel. Unlike KTM forks, the Zoke forks are valved fairly close for off road use so many times springs and oil are all you need. The base valve adjuster is used to control how fast the valving engages. Too fast and the fork dives and will feel harsh as the air spring ramps up too fast. Too slow and the fork will also feel harsh and deflect off stuff. Start in the middle range and work both ways to get the best feel. If the adjuster turned all the way in gives the best results, the valving needs to be stiffened up. All the way out, then you need to go with softer valving. Start with the stock valving. Because of the amount of free bleed in these forks, the valving doesn't engage until the fork is moving fairly fast so the low speed valving needs to be stiffer than other forks to slow the fork down once it does engage to get the best feel. Dave

[bergerhag]

Tried your setup suggestion, pobit. [post edited] I'm not happy with it. Maybe I'm having problems describing what my problems are. At a specific part of my favourit track, I'm coming in from sand/gravel flat out in fourh gear, where the terrain transitions to rocks, not too big, mainly fist size ones. The bike feel is very harsh, and every rock seems to give a 'spike'. There is now way I can keep the speed up, I need to shift down to second.
A few seconds later the track transitions again to choppy, granite rock, going uphill. Now, besides of the spikes, the bars are also yanked side to side.

Varying the clicker settings did not seem to make any difference at all at in these conditions.

When I had my previous setup, with the reduced shim stack, 120mm of oil and one lighter spring, the bike flew over all of these sections of the track, I did not even notice the choppy terrain, and I managed to go 15% faster (3 minutes) on the 7km lap.

So, where should I go now? Is there a nice middle way that I can use on my base valve, to make the bike compliant over these rocks in high speed, and still keep the bike high in the stroke in rolling whoops and steep downhills that I mentioned in earlier posts?

[Nick]

On my 05 FSE i used .45 springs, oil at 130 with stock valving. Added a few clicks to rebound and all was good in the front. I weigh 215lbs i did have to tighten the high speed on the rear considerably. I'm on an 07 now and still need to get out some more but its better than the 05 was.