How do you tune out harshness in a fork?  Is it in the base valve or mid valve?  Taking a guess I would say mv.  

Where on the shim stack would it pertain to?

Not sure but I have stiffened up the comp so much that it's getting harsh and deflecting.

Thanks fellas

What year? What bike? Rider weight & skill level? MX or Woods? Springs correct for rider weight. Shock valving overloading forks?

I'm trying to figure out what is causing the harshness on top.  What is the action that is making it harsh?  If there is not one answer to this then I will understand.  I have dialed in the compression so much that it wears me out on top of the stroke.

So which is more responsible mv or bv?

Not sure why you need a year,skill level, weight what ever.

That was a good point about the shock

Edited by eotrampman, 24 May 2012 - 06:26 PM.

OK. Good luck!

KTM-Lew, on 24 May 2012 - 06:28 PM, said:

LOL...knew that was coming.....

doc

Yup

shockdoc, on 24 May 2012 - 06:38 PM, said:

Getting predictable in my old age, huh?

KTM-Lew, on 24 May 2012 - 06:28 PM, said:

eotrampman, on 24 May 2012 - 06:16 PM, said:

It's called a mass spring damper system.

I get it.  I was a bit annoyed and frustrated yesterday before I got on tt. then trying to explain what I wanted answered was pissing me off, then Lew...(no offense Lew)

So apologies

Through my frustrations and later cooling off I am simply going to back off the rear Comp to see if it helps.

Got pissed and the obvious wasn't so

eotrampman, on 25 May 2012 - 10:25 AM, said:

The 07-08 fork tubes are about as smooth as a cheese grater. Also have issues with cartridge seal drag. So asking what year bike they are from is a valid question.

This board software sucks dog balls...I HATE trying to post more than a few words here. So that explains my frustration?

Edited by KTM-Lew, 25 May 2012 - 11:36 AM.

For starters, here is my thread all about this problem and trying to fix it: http://www.thumperta...arshness__st__0

I have not posted on it in a while (I will today) but sadly I have yet to find a good solution to the problem.

There are many things that cause fork harshness. We removed the midvalve on my forks and put in a check plate, same harshness. We went with a softer spring and less oil in the chamber, same harshness. We lowered the front, raised the rear to put more weight on the front, same harshness. We did all sorts of things to the rear end, from valving changes to bladder pressure changes, same harshness. Yet when I ride my friends 2012 350SXF, it has NO harshness at all, feels like a motorized couch!

I think part of the problem is the PDS system in general, how it likes to sag a great deal and that sag generally speaking, removes a lot of weight from the front. So the fork is basically chattering over the bumps when on the throttle because its at the top of the stroke all the time. When I put a heavier rider on my bike, some of the problems are masked because his weight pushes the forks into a different part of the stroke where they work better. So the premise is to get as much weight on the front of the bike as possible during the throttle application process. This means, less sag, lowering the front end a bit (tubes higher in the clamps) and adjusting the compression shim stack so it sits lower in the stroke on its own.

To get rid of the mid-valve harshness, I went with a check plate mid valve. The 06 SXS forks use a checkplate and then they went back to a mid valve in the 07+. Its much harder to tune a mid valve, but they DO work better in a lot of ways.

I have all the tools now to build my forks myself, so I'm focused on coming up with a solution to this issue. Even if it requires me to go back to a progressive spring and/or a stiffer rear end to keep the front pushed down, I will make it happen.  

So the answer to the question is, no there is no holy grail.

KTM-Lew, on 25 May 2012 - 11:35 AM, said:

Pretty much all the WP forks up to the 2011's have the same issues with the stiction. So for sure, stiction plays a pretty big role in these issues.

If you polish the living crap out of the fork tubes, they do work a lot better. My tubes have some stiction, but nothing crazy. With the fork apart (just the bottom/top tubes no cartridge or spring), if you compress the tube and grab the whole assembly compressed, hold it in the air and let go of the bottom part, it will free-fall straight down. The cartridge rod seal is for sure one big stiction part, but I've been told by pretty much every tuner, its not worth it. Maybe I'll try it for shitz and giggles because its cheap...

tye1138, on 25 May 2012 - 12:19 PM, said:

Oh dear!

so little knowledge

so much to learn

Good luck!

EDS, on 27 May 2012 - 12:47 PM, said:

Yep. I've steered clear of that one.

KTM-Lew, on 27 May 2012 - 02:36 PM, said:

If you know something, why don't you say it? Its responses like this which are infuriating. This is a place to get help and set the record straight. You aren't helping at all, why post something at all if its not adding to the conversation?

EDS, on 27 May 2012 - 12:47 PM, said:

Yea, when your stuck on the side of the road and nobody pulls over to see if you're ok... you know the reason why, they're just like you.

I don't understand people these days, they have no interest in actually helping anyone, they just ignore ya and keep on doing their merry thing. Its just like the suspension tuners I know. They just wanna take your money and send you back out to pasture, which is why I'm trying to absorb as much information as I can through  the internet on these subjects because nobody is willing to impart any knowledge today. I impart the little bit of knowledge I have, to help people go in semi the right direction.

If I said something that is incorrect, please correct. It will take you three more seconds to write something that imparts knowledge, then it does to write, OHH DEAR.. bla, bla, bla.

Edited by tye1138, 27 May 2012 - 06:45 PM.

eotrampman, on 24 May 2012 - 04:33 PM, said:

To try and answer the original question:

You cannot just tune one or the other.  And even if you're just using the mv and bv as your only ways to tune out harshness, you're missing out on a lot of other variables that can aid in reducing harshness.
It's nothing but a balancing act vs the mid and base regarding damping in the cartridge.
The WP CC fork def. has some shortcomings when compared to the latest Showa and KYB offerings.  
With a lot of work, you can make the WP come really close to being as good but of course that's all subjective.
And it MATTERS a lot what year bike, your weight, and a ton of other variables.
For all we know you're trying to ride an 07SX fork with all .15 BV shims in slow, rocky, terrain at a snails pace.
And if you're tuning them yourself just post all of your shimstack details along with cst of fluid you're using, spring rate/preload, outer quantity, what year forks, 2t, 4t, tall guy, short guy, fat, skinny, you get the point.  The more details the better.  People on here are really helpful if you are nice about it AND are very specific.

Thx ds1434 and everyone else

I have a 11350sxf.  .49kg in the front and 5.8kg in rear.  I'm weighing 195lb and ride Mx and woods about 50/50.  I have smart valving in front and rear.  DaveJ has been in good contact with me in solving some minor issues.  

It seems this system is not much of a plug and play setup.  Since I ride a lot of different tracks/terrain I spend a lot of time dialing in for each ride.  Usually takes 2 or 3 laps for me to get each track right.  I need to write it down.

Mostly I was wanting to learn of different ways a system can feel harsh.  Overloading forks is good one, stiction, tire pressure, air in forks etc.  Fork alignment?

If the valving is causing harshness, what are the common reasons.. And so on.

One thing I am currently troubleshooting is a lot more air pressure in the right fork when bled off.  Oil comes out and it's messy.
Dave is actually sending me some sxf seals to try out, so we will see.  He also said I should try rotating the tube so the bleed hold is in rear.  I'm willing to try any and all things.  I have been getting a crash course on this stuff going back just a couple months ago when I installed the kit.  I enjoy learning and have been really happy with his product.

eotrampman, on 27 May 2012 - 10:22 PM, said:

The front wheel is completely off the ground when you do this right?

Usually built up pressure like this is just a simple over-filling of chamber oil. I'd dump the outer chamber oil out and see how much is in there. If you have a lot of harshness, that would be FOR SURE the first place I'd look as I've ridden a few 2011/2012 350SXF's and they're brilliant stock.