fork tuning for enduros

Taffy, I still think you are way off the hydraulic sweet-spot, not many compression damping shims, clickers nearly wide open. Maybe I was lucky to fail in the right direction, and ended up on the right slope of the valley of bad damping, had I ended up on the other slope the improvements may have gone in the direction of the plateau of damper goodness (softness) instead of the mountain of damper goodness (plushness). Much of My Fork Struggle is actually condensed in this single post linked. It was added to as the development went on.
Using the compression clickers the sweet-spot seems narrow, one click off and I'm off the peak of plushness. On the peak of plushness the fork is like having ascended to heaven. Not launched.
If it was me I'd throw in more shims on the compression side, both on MV and BV, to dissipate the hits as they occur leaving little energy in the springs for the rebound to deal with, and ride a lot experimenting with clickers finding the narrow sweet-spot of plushness. If only I could give any concrete advice, the good tuners could probably, but I can't because of the lack of experience. Still I hope that this somehow can be of help.

Regards.

The method of fishing out the cartridge for the adjustment of MV speeded up the progress and lowered the threshold of getting in there a lot.
Regards

Deltas in the fork BV a good idea?

Deltas in the fork BV a good idea? Like this for instance:
24d
24d
16
24d
24d
20
18
14
12
9.5x0.3
15x0.25
No it is not a rebound stack, it's intended for the Base Valve. The idea being that deltas wouldn't be in the way for the cartridge refill. The 16 is a large diameter split shim and the idea is that it should give the 1st stage more support so that a 3 shim 1st stage can be avoided. Any thoughts, you suspension gurus?
Regards

Taffy
what works for KTM does not necessarily work for a Husaberg when comes to shocks
problem that I see is that that bulk of the needle comes into play too late to be
a real benefit or improvement over stock that said I have not tryed that set up

cheers Per

I read this subject with facination. I can not feel such small differences in any bike set up. I have ridden same make bikes but with different set ups. I have altered my riding style to overcome handling on the different set ups. I rode 3 bikes from same team during Enduro training. I could recognise that each was set up differently, but could not have specified where the differences where! I adapted to suit each bike, so could not be so precise about various set up alternatives!
I look forward to trying the above variations and then feeling each difference as I alter/adjust my settings.
I tend to train in deep sticky mud! so I should have a reference to work from as I have a stable variant of terrain and lap speed!

Taffy
raise the oil level thats the way to get progression with 48 springs you should be styling
and you dont pac the girth you should not even need 48 springs, with 48 springs fork
tends to too gt heavy handed at the first part of the travel where as raising the oil
level stronger feel at the end of travel so get on with it raise the bloody oil level and
feel the difference and change the rebound as need be when you get a fork that dont use to much travel the stock rebound is not to far off, oil level 125-120mm

cheers Per

Now, if the 48s are heavy handed in the first bit of travel and you think the sag is over the top you would not like the fork to pack since it would make your issues much worse. Maybe the opposite, unpacking it slightly would make it much better. You could try to make it unpack by dialling in more LS damping on the clickers, you'd probably need less rebound damping if you do since you'd get less launching. Unless the BV is too weak to bear the front.

If it was me I'd not remove any of the 24's in the base valve, I'd put back the 16 splitter OR add a LS 24, or even both, BEFORE altering the MV. And only then add to the MV if the HS was not overly harsh and too sharp to the hands. But that's me. And then increase speed to spend less time on the bumps.

You are probably on the right track, generally, having drawn some conclusions riding with 50% of the time on terra firma and 50% in space. Half the time means you have to have twice the force to keep the front up since it is effective only half of the time. Think of it this way: would you fit a twice as strong spring to do the additional job or would you let the hydraulics take care of the extra force needed?
Most people are not all muscle and hard as nails, sag numbers are not everything.
The air spring is a spring too and more oil would rise the spring factor even more, stick to your present level or even remove oil to 130 or 140 to get the thing more linear and add more BV shims instead. If you have added as many to the BV as you can stand when hitting stuff hard and still want to ride with a higher front then decrease the MV float another notch, but I think the 1 mm float is good and adding a 23 while removing the 14 would be an alternative.
This is only an opinion.
Regards.

Try this:

24, 24, 13, 24, 24, 24, 22, 20, 18, 15, 13, [email protected]

zp3 ran .39s, single stack BV and is fairly skinny and on a 200 cc 2-stroke, a lighter bike, a lighter guy. And a .8 mm float on a 4 shim MV too, which bore on a 30 deg tap shoulder.
You could try that float too but I bet you will be better off with more shims in the MV than was used in the zp3's skinny 2-stroke. I like 1 mm.
By all means try the lew-stack above, but keep your 14 splitter. Bring a 16 splitter to try if your smoothbleeding of the BV is smooth enough to allow it. Again just an opinion, the pudding will provide the proof regardless if I'm right or wrong and should be the guide rather than some free advice on an internet forum. But as you previously stated, talk is cheap.

Regards.

Pitching front, yes I agree and think that the rebound is ok too, even though it's hard to tell remotely. Still think the BV too weak.

i don't know smorgy, whether it's the BV or MV or both pistons i should have done this too?

Click to expand...

Sorry, didn't understand that sentence at first..., but it should be better to drill the BV smoothbleeds only, I guess. Can't tell really, haven't done it myself.

i haven't diamond papered the legs, daisy plate - worth it? should try kabooms seals sometime!

Click to expand...

Get some really heavy dielectric silicone grease instead and pack it full inside the scrapers.
regards.

Well Taffy, I've been thinking about the pitching fork...

Maybe it should have been PMed to save me from the embarrassment of being totally wrong, but it may take more than one person to put me right.

Anyway, I think that if the compression stacks are firm enough then you don't need to run a very small air gap to prevent bottoming since the increased damping would allow less travel. You will still have your bottoming cone dealing with the very brutal bottoming that occasionally will happen. The air gap is another spring, only much more progressive.




Here is my kind of way of thinking of rebound, lacking any real knowledge. Do correct me if I'm wrong. Read this several times and try to understand how I meant it.


I think of the rebound as doing two very distinctive opposite rebound damping jobs (and
then everything in between):

* Let's call the "first" job Free Air Rebound Damping.
(Edit: I now call this Drop Rebound damping. End of Edit.)
Rebound damping when the wheel is not in contact with the ground. Like when the wheel is kicked up by a root, the rebound of the wheel will then be in free air until it hits the ground or the fork tops out. This rebound movement should be fast so that the front wheel gets back to work as fast as possible. Too slow rebound will not get the fork ready for the next bump and it would mean hitting next root a lot harder, possibly launching you by bouncing hard on the tyre or, if the hit is not square, deflect badly.
The full force of the spring is on your side to do this fast rebound and you would like
the rebound stack to be weak enough open wide from the pressure created by the spring (and air spring pressure). By the end of travel the spring force will have diminished and (ideally) the rebound stack can catch the rebound movement smoothly.

* Let's call the "second" job Ground Contact Rebound Damping.
(Edit: I now call this Launch Rebound damping. End of Edit.)
Rebound damping from firm ground contact. Like when landing after a jump. The springs are now compressed and will launch you unless the rebound is slow enough to prevent it. On your side is the fact that the full force of the spring is not available to shoot out the fork.
The part of the spring force bearing the weight of the bike and rider will bear the weight of the bike and rider and is now not available to extend the fork. The rest of it will.
How great that "rest" spring force is depends on how far beyond race sag the fork has compressed on landing (with a given spring constant). You'd like the rebound stack to
be firm enough to hold back rebound enough so it won't pitch and launch.




A conclusion regarding pitching:

If you can make the fork resist compression more hydraulically then resistance will be
better higher up in stroke and the less "rest" spring force you will get to launch you
once the fork starts to rebound. If you rely more on the progressivity of the spring and
air spring to resist compression, the resistance will be found deeper in stroke leaving
more "rest" spring force to launch you.




Some conclusions regarding rebound stacks:

If you can make the rebound stack to resist the "rest" spring force on Ground Contact
Rebound well, the fork will not launch.

I try to do this in four ways,
*The springs are not too firm, this reduces the "rest" spring force.
*The rebound valve face is ground concave, preloading the rebound stack which rises the opening threshold to where the "rest" spring force has difficulties opening it.
*Keeping the air gap to where the progressivity is just enough to be comfy, letting the
bottoming cone soak up hard bottoming, which is rare anyway since
*Compression stacks are made as firm as possible while still remaining within the comfy
zone. This prevents the fork from compressing more than necessary and that reduces
excessive "rest" spring force for the rebound damping to deal with afterwards.

If you can make the Free Air Rebound to be fast, the fork will recover and be ready for
the next hit fast and the next hit will not be harsh or deflective. I try to get this by
maintaining a weak rebound stack which the full force of the fork springs easily can open
wide to extend the fork fast. I think I get away with it because of the concave rebound
valve face.
Too much fork spring preload would leave too much spring force near full fork extension
making it difficult for the weak rebound stack to dampen the fast movement and the fork
would top out hard. Same thing if a too weak BV would let out more oil than what
corresponds to the piston rod displacement, harsh topping out would result.

(A voice in the back of my head says "get a life Smorgy, you're at over 200 posts".)
Enough for now.

Regards