Suspension setup, plans, thoughts and help ?

After crashing my Meta last week a few of the lads have either sat on it or bounced on it and commented that the suspension wasn’t right. However, it could be argued they don’t know much more than me in all honesty.

So, how on earth do I go about getting it set-up ? or is there a plan I can do ?

There’s pressure of course, which I’m not bottoming out, using 85% of the travel or so. But as for the rebound, where do I go to get that sorted ?

http://locotuning.co.uk/tech-info.html for starters,

if you’re in the area we can do setup with you too.

This’ll sound like taking the piss but I’m a big fan of just fannying around with it to see what happens. There’s loads of online guides but they can be like black magic til you can translate the dials into real world changes.

Assuming it has clicky dials, figure out what your current settings are- ie, turn the dial counting the clicks til it reaches the end, then turn it back the same number of clicks, and note the clicks down. You can never go too far wrong as long as you can undo your last change.

As long as you don’t die, it’s genuinely useful to go too far and see what happens- like turning the rebound really low and really high.

There’s pressure of course, which I’m not bottoming out, using 85% of the travel or so. But as for the rebound, where do I go to get that sorted ?

So reduce pressure so you can use 100% of your travel, there should be some guidance available from Commencal for shock pressure Vs rider weight, try their website…

Rebound wise is it too fast or too slow?

Either way, it should just be a turn of the dial (remember to count the clicks)…

I’m not mate, so I need an easier plan really. I struggle with ‘feel’ in the context that the bike feels fine… I change stuff, it feels fine… but I don’t know if what I’ve changed has helped or made worse.

Rebound wise is it too fast or too slow?

I don’t know…. how does someone gauge which is too fast or too slow ?

I don’t know…. how does someone gauge which is too fast or too slow ?

Does it feel like a pogo stick, or a wet sponge?

OK try describing the suspension’s current movement in your own words if you can…

If you get off the bike and you drop it from say 1 meter up will it bounce or just suck up the impact and sit there?

If you give it a good old bounce, chuck your weight on the saddle then step back and watch, does it spring back quickly, or take a little while to creep back to full extension?

I don’t know…. how does someone gauge which is too fast or too slow ?

This is my opinions, but a good start is:
Ride off a highish kerb sat down like a sack of spuds on the seat and watch the suspension. Does it just dip and return or does it dip, return, overshoot and drop back to the original ride height? Start with it too fast (second option above) and slow it down one click at a time until it just stops overshooting. Usually that click or the one faster than that is pretty much right. You want the forks to rebound a bit faster which is most easily judged by someone else watching while you bounce hard on the pedals as you roll along. Try and keep your weight off the bars as you do this.

If you get off the bike and you drop it from say 1 meter up will it bounce or just suck up the impact and sit there?

This tells you nothing. Very few trail bikes will drop and not bounce like a DH bike often does and depending on the shock valving DH bikes often won’t either. It doesn’t mean the set-up isn’t right. You need a rider on the bike to judge the set-up.

I disagree, if it sucks it up then it could indicate there’s a lot of rebound damping, and/or a soft shock, we’re really looking for it to bounce a bit, couple that with its return movement after a bit more load and you might start to build a picture…

Next I’d ask the OP to try and describe the ride in his own words again…

Seeing as the OP just wants some pointers on setting dials, best place to start is with a bit of diagnosis.

Oh, I meant to add- did you do your own setup on the motorbike? I always feel that on the motorbike, suspension setup was almost all about controlling the bike. But with a pushbike, the hard part is controlling the suspension. Making it so that it’ll splodge up a landing is easy but making it not then ping back up or blob into the travel, not so easy.

Northwind – Member

Oh, I meant to add- did you do your own setup on the motorbike? I always feel that on the motorbike, suspension setup was almost all about controlling the bike.

No mate, I have mates who run BSB teams so I get them to setup any of my motorbikes. However, as above with bicycles I struggle at times to feel the differences

Next I’d ask the OP to try and describe the ride in his own words again…

TBH the bike to me feels I guess ‘plush’ soft and compliant.

Forks rebound:

Once you’ve set the sag, turn your rebound dial/knob to full slow. Turn the dial carefully as some fork internals are quite fragile, don’t force it! Then undo it 3 or 4 clicks or half a turn.

Compress the forks and release them picking the front end of the bike off the floor, the wheel should just leave the floor before the forks extend to their full travel.

Rebound problem solver

Symptoms: Takes first bump in a series well but harsh over later bumps, poor traction in ‘rippled’ corners

Causes: Too much rebound damping

Solutions: Reduce rebound damping

Symptoms: Springs back too quickly after bumps, poor traction in bumpy corners

Causes: Not enough rebound damping

Solutions: Increase rebound damping

Shock rebound:

Again put your rebound to full slow then back it off about one turn or 3 or 4 clicks. What you’re aiming for is for the wheel to track the ground over repeated hits such as braking bump while not being too fast so it kicks the back end upwards when leaving the ground when jumping.

If in doubt set the rebound slower rather than faster when setting up, as it’ll just pack down rather than firing you over the bars. Again it’s trial and error to find the sweet spot that suits you, just increase or decrease a small amount at a time say one click or an1/8 of a turn.

Rebound problem solver

Symptoms: Takes first bump in a series well but harsh over later bumps, poor traction in ‘rippled’ corners

Causes: Too much rebound damping

Solutions: Reduce rebound damping

Symptoms: Springs back too quickly after bumps, poor traction in bumpy corners

Causes: Not enough rebound damping

Solutions: Increase rebound damping

From above link.

I disagree, if it sucks it up then it could indicate there’s a lot of rebound damping,

What it usually means without a rider on the bike is that it has some compression damping. Very few bikes significantly actuate their suspension when dropped under their own weight only. The rider is far too big a part of the overall system weight to discount in this way. Likewise, rebound without a rider on it meaningless, particularly with the advent of commonly available forks and shocks with proper speed sensitive rebound valving (e.g new Pikes etc) since they will control the rebound very well when the weight of a rider is on the bike (i.e recovering from a big compression) but rebound very fast without it (i.e wheel is off the ground and trying to track the back of a bump)

Even at speed? over rough stuff? roots and rocks?

The rear wheel never goes a bit ‘skippy’?

How about when you pedal? how does it behave then?

cookeaa – Member

Even at speed? over rough stuff? roots and rocks?

The rear wheel never goes a bit ‘skippy’?

How about when you pedal? how does it behave then?

see, this is where I’m going to frustrate you…. sorry… it feels good on all components. You do get some occasions where the rear end feels a bit squatty, like it almost feels as though it has a flat when on an XC generic fireroad type trail and it ‘tracks’ a line in the path and feels like it’s squatting/drifting almost. This is from a seated riding position, I don’t do up out of the saddle as much as in the past as it’s an AM bike rather than an XC whippet.

Air volume maybe an issue causing the squatting, reduce air vol and pressure, also too slow rebound will cause it to squat and cause harshness over bumps.
Some propedal settings can make it feel like you have a flat on certain surfaces.

LoCo – Member

Air volume maybe an issue causing the squatting, reduce air vol and pressure, also too slow rebound will cause it to squat and cause harshness over bumps.
Some propedal settings can make it feel like you have a flat on certain surfaces

I’ve got CTD on both ends, 90% of the time I run both on T mode. Only if I’m going down something properly tough do I soften to D mode.

any air spacers fitted?

LoCo – Member

any air spacers fitted?

Bike is as it came from Commencal, so I’d assume not ?

may have one from stock, but maybe worth trying the next size up if one fitted or the second smallest for starters, it’ll make the spring curve less linear so reduce the squat and allow you to use less pressure too.

Basically you are Cole Trickle

Hmmmm, that “Squatty” sensation…

perhaps see Loco’s bit on Shock rebound above, for “Too much rebound damping”…

Symptoms: Takes first bump in a series well but harsh over later bumps, poor traction in ‘rippled’ corners

Causes: Too much rebound damping

Solutions: Reduce rebound damping

How does the rear behave over bumpy bits? anything that could feel like it “Packing down” taking the initial hit but not recovering fully for the next few?

I think before you change any damping settings though, its definitely worth going back to the beginning and checking the shock pressure and sag is set correctly, that you said are only achieving “85%” of the available travel, that isn’t a good thing, too much shock pressure will affect the damping’s behaviour also, so changing the rebound now only to later reduce the shock pressure could just compound things.

Over-sprung and over damped could well lose you grip as you enter corners…

All IMO, LoCo is Far better qualified to advise in such matters, follow the setup guide above and see how you get on…

Northwind – Member

Basically you are Cole Trickle

LOL I’m sure it’s sad… but I actually get that joke 🙂

Basically you are Cole Trickle

ooooooo?

I wouldn’t have thought people were using 100% ?

I have a question though… Do you set your maximum travel in Trail or Descend mode ? I’m assuming that in the different modes, the amount of travel is greater/lesser ?

http://www.imdb.com/title/tt0099371/

Cole Trickle enters the high-pressure world of Nascar racing. He’s a hot driver with a hot temper, and this attitude gets him into trouble not only with other drivers, but members of his own team as well

Plot[edit]

Cole Trickle is a young racer from California with years of experience in open-wheel racing winning championships in Sprint car racing. His goal was to win the Indianapolis 500 but realises that “You can’t win at Indy without a great car and my name isn’t Andretti or Unser”. He is recruited by Chevrolet dealership tycoon Tim Daland to race for his team in the NASCAR Winston Cup Series. Daland also convinces former crew chief and car builder Harry Hogge to come out of retirement and lead Cole’s pit crew. After Trickle set a quick time in a private test at Charlotte, Hogge builds him a new Chevrolet Lumina to drive in the Winston Cup, though the season has already started.

During his first few races, Cole has difficulty adjusting to the larger NASCAR stock cars and communicating with his crew while being intimidated on the track by Winston Cup Champion Rowdy Burns; this results in Cole not finishing the races, mostly due to crashes or blown engines. After discovering that Cole does not understand the common terminology used by NASCAR teams, Harry puts him in a series of rigorous training. This pays off at the Darlington race, when Cole uses a slingshot maneuver from the outside line (something real life NASCAR drivers rarely did coming out of turn 4 on the tracks old configuration (now turn 2) as most ended up out of control and into the wall) to overtake Rowdy and win his first race.

The rivalry between Cole and Rowdy intensifies throughout the season until tragedy strikes. At the Firecracker 400 in Daytona, both drivers are seriously injured after their cars are destroyed by “The Big One”. While recovering from his injuries in Daytona Beach, Cole develops a romantic relationship with Dr. Claire Lewicki, a Neurosurgeon at the Daytona Memorial Hospital who was senior doctor on duty when he was brought in after his crash and who was attending to his health. At the same time, Cole and Rowdy change from bitter rivals to close friends.

As Cole is still undergoing therapy, Daland hires hot shot rookie Russ Wheeler to take over his spot. Weeks later, Cole returns to active duty, with Daland now fielding two teams – the second car driven by Russ. Though Cole shows signs of his old self, he finds himself intimidated by his own team mate. Then, at North Wilkesboro, Russ gets dirty on pit road and spins Cole out to win the race. In retaliation, Cole crashes his car into Russ’s car following the race, resulting in Cole and Harry’s team being fired by Daland.

When Rowdy discovers that he has to undergo brain surgery to fix a broken blood vessel, he asks Cole to drive his car at the Daytona 500 so his sponsors will pay for the year. Cole reluctantly agrees and convinces Harry to be his crew chief again. Hours prior to the race, Harry discovers metal in the oil pan, a sign of engine failure, so he manages to have Daland provide him a new engine. During the race, Cole’s car suffers a malfunctioning transmission after being spun out by Russ, but the combined efforts of his pit crew, as well as those working for Daland, manage to fix the problem and get him back on the lead lap. This sets the tone for a final showdown between Cole and Russ. On the final lap, Russ predicts that Cole will attempt his signature slingshot maneuver from outside, but Cole tricks him with a crossover, overtaking him from the inside to win his first Daytona 500.

Cole drives into victory lane, where he and Claire kiss passionately while they celebrate with his pit-crew. As he looks around to see where Harry is, he spots him sitting alone on a concrete barrier near the teams pit stall. Cole walks up to Harry and challenges him to a foot race to victory lane

I’m just going to add an important note here, which i think is quite important:

Having the perfect “optimum” suspension settings is not actually a lot of use on a bike unless you are actually racing against the clock, and in that case, the settings you will end up with will pretty much be too extreme for most normal riding.

The point i am trying to make is that “optimum” is not one dimensional. We can consider many different factors in the dynamics your suspension, both in the time domain and the frequency domain. And all those factors are inter-related!

For me, simply having a “ball park” set of suspension settings, that on average mean the bike responses in a similar and repeatable fashion to pretty much every kind of terrain i encounter is the most important factor. Unless you are going to use objective measurement techniques then this is what you too will end up with.

Unlike say a motorbike, which in reality only has to deal with a few primary /secondary ride situations, a mountain bike has to deal with a massive variation in riding conditions, from rolling smoothly down a pebble covered wide double track to being hucked off a 4foot tall step down into a root infested landing etc!

Unless you suspension is soo far out that the bike is actually bucking around under you (which tbh, is unlikely, as most forks/shocks simply don’t have a wide enough range of damping co-efficient adjustments) then you certainly shouldn’t be actually crashing because of your suspension settings! (no, you might not be going optimumly fast, but it shouldn’t be taking you off the bike!!)

The worst thing you can do, imo, is to chop and change your settings so much you haven’t got time to adapt and learn how the bike responds. Even with a poor choice of say compression damping, your brain will just adapt and learn to ride around that deficiency, as long as it is repeatable. If you keep changing things you will NEVER learn your bike, which again, imo, is the most important factor of all!

The second point (in this rather long winded post) is that the “best” settings are the ones you are happy with. If someone else sits on your bike and says “your damping is all wrong”, well, so what? If you’ve been riding it fine like that, leave it alone!

Which Meta are we talking about? Mine is a 2013 AM CTD rear although I’ve still to really experiment with the settings. Mojo without asking almost straight away put a spacer in and it made a huge difference – a bit more support, less fidgety and more progressive.

I run it on Decent on anything pointing vaguely downhill with 6 clicks from slow. All I did was roll off a kerb a few times and stopped tweaking when the shock felt as if it was not topping out harshly on rebound. Another way I’ve found useful is to roll down some steps slowly and again stop tweaking when the rebound stopped pogoing the bike upwards. The rear seems fine to me, but I now want to experiment with a faster rebound on fast trails with small to medium hits. In terms of travel I just kept tweaking the psi until almost all is used up on my normal riding, with a bit in reserve for bigger stuff.

EDIT: I set my bike up in decent rather than trail.

Oh, and, in addition (sorry)

iirc, your crash at Swinley was in the jump gulley, persumably after hitting one of the 4 jumps there?

If you are setting a bike up for single, non repetitive large jumps, and want to give yourself the softest easiest landing possible (to help you land successfully whilst you nail your jumping skills) then in reality you simply want to wind on max rebound. Because each of those jumps is individual and separated by a large distance, the landings come at such an interval, with a relatively large “air time” in between that your suspension will have plenty of time to extend to it’s max between the landings. This will make the bike come back up after the landing as slowly as possible, helping you stay on if you make a horrible mess of the landing etc!

In terms of air pressure, because of the effective “square law” in airsprings, just about any landing hard enough to actually fully compress your suspension is probably going to have you off the bike if your core position and technique is not nailed, no matter what static pressure you run with.

In this case, when jumping, it’s 99% technique, 1% bike & suspension………. 😉

AM2 29 mate on a 2013 also.

maxtorque – Member

Oh, and, in addition (sorry)

iirc, your crash at Swinley was in the jump gulley, persumably after hitting one of the 4 jumps there?

If you are setting a bike up for single, non repetitive large jumps, and want to give yourself the softest easiest landing possible (to help you land successfully whilst you nail your jumping skills) then in reality you simply want to wind on max rebound. Because each of those jumps is individual and separated by a large distance, the landings come at such an interval, with a relatively large “air time” in between that your suspension will have plenty of time to extend to it’s max between the landings.

But again, in this case, when jumping, it’s 99% technique, 1% bike & suspension……….

Don’t get me wrong mate, this wasn’t relating to the crash, nor any other incident/accident etc, this was purely because I’d been chatting to a couple of people who’d bounced on it when recovering the bike for me etc

It’s not really relating to the jump settings being right or wrong, just generic riding stuff.

With the CTD shock?

oh, ok, cool, i just read the “after my crash” bit in your original post and wondered if you were thinking about that 😉

maxtorque – Member

oh, ok, cool, i just read the “after my crash” bit in your original post and wondered if you were thinking about that

Sitting in bars over the last week in Morzine while my mates were out riding, yeah I’ve been thinking about that crash quite a lot.

More along the lines of “why didn’t you bloody wait until you got back from Morzine before practicing jumps more you complete spazzo”, rather than “my bike tried to kill me…”

lol! Well, if you never try something, how are you going to learn to ever do it?? 😉

I suspect, knowing where you ride, you probably need to try to work out two basic setups:

1) an XC set up, that runs a soft initial pressure setting, lots of sag for comfort (especially at the front, for those horse cutup bridleways), but where you don’t need the suspension to deal with big single impacts or stay “high” in it’s travel to maintain geometry when descending steep terrain etc

2) an “AM” setup, that is going to keep the bike higher in it’s travel, resist brake induced sag, have a harsher initial ride but keep the bike more active through big repetitive hits (roots, rocks etc)

In reality, unless you have a shock/fork with sufficiently wide range of damping co-efficient adjustment then you are limited most probably to changes of the static air pressure in those elements as the biggest factor.

Idiots guide to suspension (devised by me – a suspension idiot)

Disclaimer: The following guide isn’t even close to perfection but it works ok and wont kill you 😀

Rear:
Flick switch to descend mode as that’s when you need need the suspension to work.

Set air pressure to what’s recommend for you weight. Adjust for desired sag.

Set rebound to middle and push your weight onto the saddle then release.

Note how fast the rear returns – then slow it down a couple of clicks – you want the rear to return slightly slower to stop you getting bucked about*.

HSC/LSC – if you have them set these to middle and leave alone (we’re idiots remember 😀 )

Front:
Again set air pressure and sag.

Set rebound to middle and compress the forks. Slow it down a bit if you want – do not speed it up – even an idiot knows this.

Again set any compression setting to middle and leave alone.

You are done.

Go ride it a see how it feels on a trail (street/curbs will tell you nothing useful). You may want to adjust the air pressure a little (i run mine firmer than recommend with about 25% sag). You can also tweak the rebound a bit too.

If you still aren’t happy with how the bike feels then take it to loco to get it set up properly 😀

* Here’s what can happen if the rebound is too fast (new bike using previous owners rebound settings)

And after a bit of idiot fiddling (just slowing it down really)

Much betterer 😀

One interesting and quick test you can do to help get rebound settings matched is to just get into the normal “centered, pedals level” position whilst slowly coasting along in a straight line at low speed (what ever speed is low enough for you to feel balanced and stable on the bike), then pump down hard into the pedals(crouch->standup, do not lift the bars!) and check that the bike bounces up into the air level.

This is because a “matched speed” of rebound front/rear is more important generally than the absolute value of that speed.
It’s an interesting and quick exercise to deliberately set one end of your bike to max rebound, and the other to min and repeat the test, then swap which end is max min. Doing that helps you to feel what those changes are actually doing to the bike and how it responds.