suspension gurus

gg3

Silver Level Site Supporter
I am getting my suspension dialed in & have the shock sorted.But I am crap at interpreting fork feed back so need you guys to tell me what to adjust for this behavior- sits up nice through whoops & choppy stuff,handles roots & rocks nice but through berms/rutted corners it enters nice but then want to run wide or climb out of the berm?It really is fine tuning as it generally works great.Correct springs & sag have been done.Any suggestions welcome except get fit or eat healthy.
 
Incorrect mid stroke valving can produce the symptoms you described.
Rear sag maybe too soft, also.
 
Sounds like a geometry issue rather than springs/ valving. Before going back inside the forks, you might try sliding the forks up in the clamps to the next "ring" (lowering the front of the bike.) What is your rear sag? Raising the forks will have a similar affect as running less sag in the rear.
 
Thanks Guys,that makes sense with the geometry.I don't want to make it unstable on open stuff like my KTM ride mates,it is really stable at speed .
Sag figures- 34mm & 120mm
It is a 2014 model so how do those figures look?I have my forks 5mm through the clamps at the moment.I assumed the sag is correct as I had a shop set it up to my weight.Should know better.
 
Valving is speed sensitive, so to say mid stroke valving is kind of void. Spring can play a huge influence deeper in the stroke though.

Work with your rebound a bit before you get too carried away gg3. Slow it down a few clicks (close the clicker) and see if it improves. Sometimes if its rebounding too fast it won't 'settle' mid corner and will try to stand up or run wide. Same goes for climbing out of ruts. If you slow it too much it'll pack down in the whoops and trail trash so always a compromise. Often a click or two is all it takes once you're in the working zone.
 
That is exactly what it is doing in corners.Also occasionally I hit a whoop & do a 'bounce' wheely-too fast front rebound? Feels pretty cool when you power on & hold the wheely though.
How do these Sag figures look? - 34mm & 120mm
 
Definitely start by reduce/slow front rebound(bottom of fork clicker).screw in 2 or 3 clicks at a time and ride over same bump,same speed so you can feel the difference. Or stand on pegs and bounce bike,pay attention to which end rebounds faster and try and get them balanced roughly with the clickers.you can add rear rebound also but too much and the rear will 'kick' off logs and square edges.once you get rebound close finetune with compression.based on that sag you may well benefit from a stiffer spring or increasing the preload a turn or two.
FWIW heres my 13 with ohlins 88 shock,zokes 48,me 75kg
on the bounce test(stock)front was down and back up the stroke noticeably quicker than rear.

front rebound 13 from full in(stock 20)7 slower
rear rebound 21 from full in(24)3 faster

front compress 16 from full in(14)2 faster/softer
rear compress 13 from full in(15)2 slower/firmer

pfp 1/2 turn in from full out,less preload! (stock 2 turns in from full out)
race 97mm/static 39mm(im bordering on light for this spring i think)

bike used to kick front up over jumps and try and wheelie hillclimbs too,now its much more balanced.also way less tiring on the arms!initially i liked the shock action but found the fork too firm/harsh so concentrated on fork,slowing rebound/softening comp,reducing preload(external pfp).eventually found i had too stiffen comp,quicken rebound,tighten sag on shock also to get to where im happy enough.next step fork would be internal tweaking of rebound and less seal stiction,maybe less preload
 
Great info guys,looks like I need to reduce the sag & slow the front rebound a couple of clicks.Understand the principle now of why it is behaving like it is.Will try it out this weekend.Awesome forum as usual.
 
Definitely also address the back end gg3. You may find you want a heavier spring.
The static looks good, but the race sag at 120mm is far too much for the new chasis.

On my 2010 I could get away with anywhere from 105-120mm race sag but did prefer to run it less than more. On the 2013 chasis I set it at 98mm using a 5.4 rate spring which nets me 32mm static. With the Ohlins 888 the comp stack wasn't bad, but the rebound circuit had to be closed up which in turn reduced bleed on the comp stroke. After a couple of changes to the rebound stack I'm now at a point where I feel I can run the rebound open enough to keep the back end up in the stroke, allow enough bleed to have the initial comp movements supple, and yet still provide damping to stop the shock unloading quickly off the sharper hits.
 
After I got it back from the shop the rear settings & spring rate felt much better.After following me, a friend suggested opening up the rebound.We eventually went 6 clicks out & it transformed the bike in stability,traction & cornering. Unbelievable difference,I was a friken legend for the rest of the day(in my mind). So there may be more gains to be had with rear adjustment as well.
I was running the same sag figures on my 2010 as well.
 
I think Mr Jakobi nailed it...

I would add the following to discriminate between sag being off and rebound being off...

If it starts "pushing through the corner right away" then it might be sag. Your steering geometry is off from the get go.

If it won't "hold a line' and tries to push through in the manner described - then it can indicate your rebound dampening is off. I bought WP 4054s upside down fork kit back in the late 1980s to put on an xr250r (it was from white brothers) - it came with a great manual and a description of this symptom and the cure. If you have too little rebound - what is happening is fork comes up as you are in apex of turn (for example) - this rakes bike out loosening the steering geometry as you are mid-turn (or there abouts...)

From my experience, I would add one additional thing to Jakobi's most excellent response. In the past I would find a section of trail or track where there was a section of whoops and a corner(s) that exhibited the issue - I would repeatedly take this same section while adjusting the fork rebound to dial it in. Ensure fork doesn't bottom on whoop section as you are making adjustments - to ensure the fork isn't "packing" as Jakobi described.

Jeff
 
Brilliant description thanks Jeff.
Entering the corner is fine but from mid corner/apex is steers wide or wants to climb the berm- Rebound! Will start there.
That manual with the symptoms & cures sounds interesting.Any chance of scanning it & posting up?
 
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