Compression/Rebound Settings - Confused?

[gasIdaho]

I see different terms used when adjusting the shock and fork clickers. Some use the amount of clicks away from completely shut. Other use terms like "slow down" or "speed up " compression.

By increasing the number of clicks, this is a positive adjustment in terms of what the arrows on the shock show. Does this mean I'm increasing the speed or damping..or both. Seems like if you are increasing "damping" then your slowing down the action of the fork

Chime in...cheers

 

[GMP]

The closer an adjuster is to closed (fully CW), the less oil flows through the bleed circuit therefore there is more damping. More damping slows the relative action, whether it is compression or rebound.

 

[KicksonR66]

I too am alway's confused and have to read someones instructions or tips every time I want to make an adjustment, here is an article by Ricky Johnson on this topic but there are several out there. Hope link works.

http://dirtbike.off-road.com/dirtbike/article/articleDetail.jsp?id=264361

 

[jeffd]

Adjustment should be done with "full in" being the reference. I usually make it clear what I am doing and where I am at by saying " X clicks out" as a reference versus using clockwise or counterclockwise or more or less. An increase in compression - I would say "I went 2 clicks in".

A few random thoughts...

The amount of change with one "click" depends on "where you are at". For example - If you are at 6 clicks and you go to 8 - it will change things alot. While if you are at 18 clicks and you go out 1 click it won't change things much.

Some things not mentioned in the above article...

Symptoms of too much rebound at either end, at least for me, is a feeling that you are not "connected" to the ground - over slightly choppy terrain the bike will skip across instead of tracking across the ground "staying connected". For my tastes and riding terrain, good low speed rebound is the ability to stay hooked up over rolling whoops, whereas good high speed rebound is the ability to stay hooked up over roots and rocks (must return quickly when the shock is totally unloaded to stay on the ground).

If I am not sure the bike is "packing" or not - I run through the same set of whoops repeatedly and play with the rebound clickers - if it bottoms on the third or fourth big whoop then it might not be returning fast enough. If I go 'too far' in backing of the rebound - it will feel "springy" and it might kick me in the butt on the first whoop. I use the term "springy" to differentiate it from the feeling when the compression is too hard and it doesn't give on the bump - for me, this is more like "hitting a wall".

Also, one symptom of insufficient fork rebound is that the bike will "push" through corners or not hold the line part way through the corner. This is because the fork is compressed as you brake into the corner along with centripetal force - this tightens up the fork geometry. (less fork angle and less rake). If the fork rebounds quickly while you are in the corner, it has the effect of "raking the bike out" - make it steer more slowly. I check this by repeatedly taking the same corner and check for "pushing". I suppose it depends on where you are at - but it seems like I will feel this at, or slightly after, the apex of the turn.

First off, I am a 47 year old rider - Les reminds me that I am no longer an "A rider" (expert) - I used to be one... . These days, I like to dial my suspension in for comfort on long trail rides at a brisk pace and I like my suspension soft. I enjoy tight and twisty stuff and am not much of an adrenaline junky as far as really high speed terrain goes. So I don't mind it bottoming hard in whoops and I will slow down for them. Given this, I will sometimes just adjust my suspension soft on compression until the bike wallows a bit (when braking or hitting something moderate in size) - then I go a couple of "clicks in" until it is stable.

I suppose that someone with different terrain, preferences or "testosterone level" might go about it in a totally different way...

jeff

p.s. Sorry for the long, long post!

 

[gasIdaho]

Excellent information. I appreciate the time and effort! I ride mostly sandy/rocky/hilly desert right now until the snow melts up high. I like the way my bike handles in the washes and whoops at high speeds. My settings are very close to Les's baseline settings on a stock fork

The one area I need improvment on is when jarring bigger rocks, sharp dirt edges or rock strewn washes. My front end is all over the place and feels like I'm hitting a sharp curb with a flat tire (rim to rock feel)....it's scary! I'd like to 'butter' through this stuff a little more. I realize this suspension stuff boils down to repeatitive testing. I'd like to understand the mechanics behind the adjustments I make as much as possible. Cheers

 

[GMP]

Thats an excessive high speed compression damping issue, classic problem. Unfortunately the clickers only alter bleed which affects low speed compression. You need to send it out to Les for a shim shuffle, very few if any stock valving setups work well in rocks.

 

[KicksonR66]

I enjoy your posts and am going to copy, paste, print. More long posts please!

 

[bergerhag]

Any 'universal' shim fix I can do myself to setup for real serious rock and root bashing?

I understand now, thanx GMP, that clicker is only slow speed. I went from fully closed to fully open in compression clickers, but it still feels like the bars are being ripped out of my hands when hitting large roots and rocks.

I even tried to use 5wt oil, no difference. Still hard as h*ll on my hands. I want a smooth rinde over logs, andr rocks an all kinds of loose debris.

I dont do any big jumps, so an occasional bottom out is ok.

So help me. please.

I'm 116kg in full outfit, I run one 4,2N and one 4,6N spring in front.

I have the '05 zokes fork on the FSE450.

 

[OhlinsUSA_tech]

Skinny:

Modern suspension has come a long way. In the old days you did not have any external adjustments. The internals were not all that sophisticated either. It was a hydraulic system with a hole in a tube & a certain amount of oil was forced through these holes. Nowadays, there is a lot more stuff going on inside your forks & shocks. Basically it is like this: your shocks & forks hit bumps & dips on the trail & they move in & out with a certain amount of resistance to keep your tires on the ground which gets you good traction. Suspension is always 'compressing' & then 'rebounding'. Ideally you want the suspension to compress easy enough so you don't get beat up by every little bump on the trail. But you don’t want it so soft that is wallows or bottoms out everywhere. After you pass the bump you want the suspension to rebound & stick to the ground & be ready for the next bump. So the suspension is compressing & rebounding fast or slow depending on the obstacles you are hitting. When somebody says “high speed” or “low speed” they are talking about the suspension movement (in & out). Not the speed of the motorcycle. It is the speed of the suspension. If you are in the garage pushing up & down on your suspension, this is “low speed”. When you are out on the trail & you hit a log or root, the suspension moves very quickly. This is “high speed” damping. Inside your suspension oil is being forced through many different channels, holes & past small steel washers called 'shims'. The holes can be large or small but will ultimately flow only as much oil as can fit through that particular hole. Oil flowing through a hole is usually low speed action. As the flow of oil reaches its limit it will then open up a secondary shim stack and/or spring loaded shim ‘pack’. Inside modern suspension systems there are damping pistons. These pistons have holes or slots which are covered up by a set of stacked steel washers or shims. With different forces of oil against these shims they will flex back a certain distance & allow oil to flow through. The arrangement of these shims, their stacked height & individual thickness all dictate how much oil will flow. Many companies have sprung up that will “re-valve” your suspension. These companies are rearranging the shim stack inside to better suit the individual rider’s taste. MX, off road & street bikes all use different shim packs & the changes are infinite. Beyond this internal damping system most modern suspension systems have external adjusters. These are (for the most part) convenience items intended to allow the user a broad choice of movement control. MX riders like stiff settings, off road riders like soft suspension, etc. Theoretically with the simple turn of a knob both riders can ride the same bike.