[Udi]

And in steeper and rougher courses, wouldn't one need a softer setup to get maximum traction? Of course too soft fork is bad on a steep track, as fork dive isn't desired on those circumstances, but I would think the suspension's ability to keep the wheels on the ground is also very important.

I think there will always be a bit of a trade-off, but in my experience, on some of the steepest tracks out there (at least in Europe) - given the right tyres, traction isn't something that is usually a huge struggle. Wet roots will cause traction issues but technique (followed perhaps by tyres) play a much more important part than suspension here.

What I found was, once I had the right technique and tyres, traction wasn't something I was struggling to achieve - however support was. There were plenty of super steep sections into hard corners / g-outs where the limiting factor wasn't grip, but the worry of flipping / faceplanting due to front-end dive and having to slow down to accommodate this.

I found that increasing compression damping (along with increasing fork A-C height and thus slackening the HA) allowed me to go faster even though it would increase harshness after a certain point (which Steve has detailed above). Holding on towards the end of a run with this setup was a lot more physically demanding, but it definitely meant I could hit steep sections much faster. The fastest setup is never the the most comfortable setup, but don't confuse comfort with traction.

Bottom line - on super steep courses (given the right technique and tyres), you'll usually run out of support before you run out of traction. Running softer suspension setups to address supposed traction issues is probably going to leave you with slower overall times.

 

[Verskis]

Surely the fastest setup is not the stiffest one, there has to be a compromise where the grip and stability are at the optimum level for a given track/rider, otherwise a fully rigid bike (with a proper DH geometry) would be the fastest under a rider that has enough power and stamina to be able to control the bike under horrible hammering.

And how about the "less hanging up" effect of the softer suspension? Wouldn't stiff suspension be slower on a rough, square edged straight, where the only factor of speed would be how much each bump slows you down?

 

[Steve M]

Surely the fastest setup is not the stiffest one, there has to be a compromise where the grip and stability are at the optimum level for a given track/rider, otherwise a fully rigid bike (with a proper DH geometry) would be the fastest under a rider that has enough power and stamina to be able to control the bike under horrible hammering.

And how about the "less hanging up" effect of the softer suspension? Wouldn't stiff suspension be slower on a rough, square edged straight, where the only factor of speed would be how much each bump slows you down?

For sure, you can go too far with any setup philosophy. What we are saying here is that the limiting factor in how much support your suspension can give you is typically your physical strength - you'll never get anywhere near a rigid bike before you simply couldn't hold on at all. What Udi says is correct, suspension is usually more useful for handling and stability than it is for outright grip.

Stiffer suspension will be slightly slower on a rough square edged straight provided you aren't on the brakes at all (surprisingly small amount of time per run - take note of it next time you ride a remotely steep track), but I can safely say that the tested time differences we measured and mentioned previously were taken on some of the rockiest, most hang-up prone sections of track you'll find. The stopwatch shows us that the benefits distinctly outweigh the detriments in terms of outright speed.

Again though, go too far with it, and you'll end up with a setup that you just can't hold onto or ride hard enough to make use of. Firmer setups REQUIRE that you actually ride faster to maintain the same tracking, because otherwise the wheel won't use enough travel in compression to have a sufficient amount of negative/rebound travel available to keep the wheel tracking through dips/holes. However, before you reach this point (unless you have some seriously weird setup), you will end up with a painful setup that you just don't want to punch out runs on because your hands feel arthritic.

 

[norbar]

Again though, go too far with it, and you'll end up with a setup that you just can't hold onto or ride hard enough to make use of. Firmer setups REQUIRE that you actually ride faster to maintain the same tracking, because otherwise the wheel won't use enough travel in compression to have a sufficient amount of negative/rebound travel available to keep the wheel tracking through dips/holes. However, before you reach this point (unless you have some seriously weird setup), you will end up with a painful setup that you just don't want to punch out runs on because your hands feel arthritic.

Either my setup is weird or my hands are but I've reached the point of lower traction in my fork. It was <15% sag if I'm right and it was on a fairly flat track with flattish berms. I'm pretty sure it wouldn't be a problem on the trails Udi rode

 

[DMdh]

Then, in general, you have to set up it firm without going over the point where you can´t create enough rebound to make the tyre track?

 

[boylagz]

Ive read all the inputs here and is real interesting and informative. Thanks to the op for starting this. I have my knowhow on suspension setups and my setup is kind of in line with what Steve and the other guys have said. My local trails are not in general super steep but some sections ARE. After getting a new fork a while back I found it too dive-prone. The lsc didnt help much but it has air volume assist, making my front end stiffer. I love this setup now. I can live with the stiffness in the fork and I like it that way actually. Feels better on those steep sections, and dont bob as much pedaling to regain momentum.
As for my rear, I set it up relatively slow although I change the rebound and hsc from time to time depending on the trail. Having a slower rebound set defo hurts on the rough. I sometimes compensate comfort for the bikes ability to handle smoother lines and of course, speed better.

 

[DMdh]

Ive read all the inputs here and is real interesting and informative. Thanks to the op for starting this. I have my knowhow on suspension setups and my setup is kind of in line with what Steve and the other guys have said. My local trails are not in general super steep but some sections ARE. After getting a new fork a while back I found it too dive-prone. The lsc didnt help much but it has air volume assist, making my front end stiffer. I love this setup now. I can live with the stiffness in the fork and I like it that way actually. Feels better on those steep sections, and dont bob as much pedaling to regain momentum.
As for my rear, I set it up relatively slow although I change the rebound and hsc from time to time depending on the trail. Having a slower rebound set defo hurts on the rough. I sometimes compensate comfort for the bikes ability to handle smoother lines and of course, speed better.

Why putting a slow rebound???

 

[boylagz]

^ I set my rebound fairly slow because Im mostly on jumps/doubles and flowy-ish trails. Im still fairly new and I want more forgiveness when I screw jumps and stepdowns. And Im used to this setup so much I barely change it. The only time sped this up a little was riding in Northstar this past summer. Which was ridiculously short...

 

[Steve M]

Either my setup is weird or my hands are but I've reached the point of lower traction in my fork. It was <15% sag if I'm right and it was on a fairly flat track with flattish berms. I'm pretty sure it wouldn't be a problem on the trails Udi rode

<15% sag is pretty stiff! And yeah absolutely, flatter tracks generally mean you can run softer fork springs and/or stiffer rear springs. It's all about the spring bias relative to the gradient you're on, if the gradient is steeper you need to be held up more at the front than the back.

Then, in general, you have to set up it firm without going over the point where you can´t create enough rebound to make the tyre track?

If by "create enough rebound" you mean use enough travel in compression to give yourself enough negative travel in rebound, then yes, that's a good way of looking at it.

 

[norbar]

I think it has to do with AVY and Craig suggesting I go under 20%. I'm at 20% flat, maybe a tad under now. That 15% experiment was on a very fast track though. Due to 2 injuries I've spent my whole season on faster tracks so that may be one reason why less sag worked good.
Actually this topic and your comments especially encouraged me to play with different setups on different tracks and make some notes. Sportstracker or a stopwatch and I will see what works best where. If only it wasn't -20 to -29C right now.

 

[DMdh]

I think it has to do with AVY and Craig suggesting I go under 20%. I'm at 20% flat, maybe a tad under now. That 15% experiment was on a very fast track though. Due to 2 injuries I've spent my whole season on faster tracks so that may be one reason why less sag worked good.
Actually this topic and your comments especially encouraged me to play with different setups on different tracks and make some notes. Sportstracker or a stopwatch and I will see what works best where. If only it wasn't -20 to -29C right now.

+111111111111111
steve m , you´re a genius

 

[Bronco!]

Very instructing an helpfull information Steve M. Thanks alot.
For personnal information, what are you doing for living, where did you get this knowledge?

 

[Steve M]

Very instructing an helpfull information Steve M. Thanks alot.
For personnal information, what are you doing for living, where did you get this knowledge?

No problem. I'm an engineer with a suspension obsession, but as for what I'm doing for a living, keep an eye out later this year

 

[iRider]

Just curious how you guys measure sag. Are you talking about static sag or dynamic? In my experience a fork or shock can ride lower or higher depending on the lsc and rebound settings although the static sag is the same. But I can't really figure out how to measure it besides 'feel'.

 

[norbar]

Static sag so you measure the spring only. LSC and HSC are separate adjustments and I think they've been covered more. Though some good points about them here too.

 

[Steve M]

Just curious how you guys measure sag. Are you talking about static sag or dynamic? In my experience a fork or shock can ride lower or higher depending on the lsc and rebound settings although the static sag is the same. But I can't really figure out how to measure it besides 'feel'.

Sag refers to static sag - in motion it's usually referred to as dynamic ride height. I just found this vid that shows a fork I built a damper for a couple of years ago, with a very high dynamic ride height. For those who know Whistler, this is one of the flatter trails - the dynamically high setup obviously is more suited to the steeper stuff where it's getting worked more. A few things you may notice:
- More travel used on the lips of jumps than on the landings
- Very good stability (not much pitching or bucking of the bike even in the rougher sections)
- Quite fast rebound (a tad faster than I think is ideal)
- The faster you go, the lower the dynamic ride height!

 

[iRider]

Sag refers to static sag - in motion it's usually referred to as dynamic ride height....

Thanks for the clarification. So how do you measure ride height besides feel (or strapping a camera to your DT)?

 

[Steve M]

Thanks for the clarification. So how do you measure ride height besides feel (or strapping a camera to your DT)?

Data acquisition if you really want to do it accurately, but other than that, it's just by feel. You can set your own suspension up purely by feel, but it's a bit harder to do someone else's with anything other than numbers.

 

[Mo(n)arch]

- The faster you go, the lower the dynamic ride height!

And that's why you can ride a stiff setup faster if you are able to hold on. Ask the pros.

Lars Sternberg from Transition bikes mentioned somewhere that he's riding the next stiffer spring in fork and shock during the race season. For the off-season he goes back to the softer setup.
He said this way he can ride his bike for fun the whole day long during off-season.

 

[dustyyoungblood]

So tuning a bike suspension for FUN, COMFORT, or SPEED is really very different settings for each... I always just figured the "correct" adjustments will give me the BEST performance/comfort/fun/speed period. Sort of a magic equilibrium, where everything is working in perfect harmony regardless of the track. And once I find it I can just glue my adjustment knobs..... Not the case.

 

[Steve M]

So tuning a bike suspension for FUN, COMFORT, or SPEED is really very different settings for each... I always just figured the "correct" adjustments will give me the BEST performance/comfort/fun/speed period. Sort of a magic equilibrium, where everything is working in perfect harmony regardless of the track. And once I find it I can just glue my adjustment knobs..... Not the case.

Pretty much - there is no "ideal setup". Every little detail makes a difference, in the suspension components themselves, the rider and the terrain. It's really a matter of prioritising what you want out of your bike, in terms of stability/handling, comfort and playfulness. Generally speaking, if you're trying to go fast and you're confident on the bike, stability and handling are your first priority, if you want a more playful bike without being solely concerned with speed then playfulness/liveliness is your priority, and if you're less confident on the bike or just happy cruising, comfort is probably your main concern.

 

[Mo(n)arch]

So tuning a bike suspension for FUN, COMFORT, or SPEED is really very different settings for each... I always just figured the "correct" adjustments will give me the BEST performance/comfort/fun/speed period. Sort of a magic equilibrium, where everything is working in perfect harmony regardless of the track. And once I find it I can just glue my adjustment knobs..... Not the case.

No, not really. Therefore the worldcup guys ride a completely different setup than a bikepark weekend warrior. The pros only have to hang on for a 3 minute run where they have to be as fast as they can.

 

[norbar]

So tuning a bike suspension for FUN, COMFORT, or SPEED is really very different settings for each... I always just figured the "correct" adjustments will give me the BEST performance/comfort/fun/speed period. Sort of a magic equilibrium, where everything is working in perfect harmony regardless of the track. And once I find it I can just glue my adjustment knobs..... Not the case.

I tend to stay with my settings for longer periods of time but one setting never works. Even a few years ago I used to setup my susp different for dh tracks and different for park stuff. Now after making my fork firmer I think I will use the fact that it's air sprung to dial it for different tracks. Slow and flat will have to be softer but on full on steep or fast dh tracks I will try even firmer I think I will get enough support in turns.