Suspension tuning quiz.

[Tim29]

Here a quiz i have for those who actually tune on there bikes suspension,
Keep simple answers. Example. If i turn the compression in 3 clicks does it affect rebound, if i open rebound clicker does it affects the compression.
Please don’t be shy, those that have no clew how to answer those would be helping me the most

1- rebound clicker what does it affect when you open it several clicks.
2- If i add air to fork how does it affect mid stroke comp and rebound.
3- If i add a volume spacer how does it work, what affects will it have.
4- coil over -If i install a stiffer coil spring will it make the bike stiffer or softer in first part of the stroke
5- coil over, will my rebound have any affect with a stiffer spring.
6- If i speed up rebound on front forks what will happen on jump
7- If i stiffen rear shock comp what will happen on a jump face/ take off
8- If i speed up front rebound will i put more or less pressure on front tire in turns.
10- front end is nervous at speed and feels like i have no traction. What do i do.

 

[Tim29]

I give a little start.
Some may not know that when you adjust the rebound on your fork or shock you actually make a change to the compression in equal amounts.
The rebound clicker works by opening a bleed port, the more you open it the more oil bleeds through that port and bypasses the valving and piston flow.
But there only a couple model shocks that have a check valve that only allow oil to flow in one direction.
So if you close your rebound knob two clicks you also closed your compression to clicks.
So if you want to speed up your rebound and open it 3 clicks you need to close your compression clicker 3 clicks to maintain the same compression settings and truly only adjust the rebound. This is why your bike feels plusher in chowder when you only open the rebound, because you actually opened the compression and rebound

 

[eFat]

I think we will need some diagrams...

 

[Doomanic]

Or a Shockwiz...

 

[Dax]

1. Speed of the rebound stroke. Open means faster rebound.
2. No idea
3. Volume spacer will firm up the bottom end of the travel, so you can run less air and have more small bump sensitivity, without bottoming out.
4. Stiffer
5. Yes. Damper adjustments are independent of the spring.
6. More risk of getting spat on the landing.
7. No idea
8. More, the spring is returning quicker and loading the front more.
10. Check sag, check compression isn't too hard, check rebound isn't super fast, let some air out the front tyre.

 

[Tim29]

Or a Shockwiz...

They actually work quite well for basic setup guide.

 

[Al Boneta]

Here a quiz i have for those who actually tune on there bikes suspension,
Keep simple answers. Example. If i turn the compression in 3 clicks does it affect rebound, if i open rebound clicker does it affects the compression

1- rebound clicker what does it affect when you open it several clicks.
2- If i add air to fork how does it affect mid stroke comp and rebound.
3- If i add a volume spacer how does it work, what affects will it have.
4- coil over -If i install a stiffer coil spring will it make the bike stiffer or softer in first part of the stroke
5- coil over, will my rebound have any affect with a stiffer spring.
6- If i speed up rebound on front forks what will happen on jump
7- If i stiffen rear shock comp what will happen on a jump face/ take off
8- If i speed up front rebound will i put more or less pressure on front tire in turns.
10- front end is nervous at speed and feels like i have no traction. What do i do.

This is awesome,
But maybe what would be more helpful, instead of a quiz, would be to go through your ten questions and explain the answers to the riders on the forum.
Maybe then have a quiz

 

[Doomanic]

Some may not know that when you adjust the rebound on your fork or shock you actually make a change to the compression in equal amounts.
The rebound clicker works by opening a bleed port, the more you open it the more oil bleeds through that port and bypasses the valving and piston flow.
But there only a couple model shocks that have a check valve that only allow oil to flow in one direction.

A list of shocks would be good here.

 

[Tim29]

1. Speed of the rebound stroke. Open means faster rebound.
2. No idea
3. Volume spacer will firm up the bottom end of the travel, so you can run less air and have more small bump sensitivity, without bottoming out.
4. Stiffer
5. Yes. Damper adjustments are independent of the spring.
6. More risk of getting spat on the landing.
7. No idea
8. More, the spring is returning quicker and loading the front more.
10. Check sag, check compression isn't too hard, check rebound isn't super fast, let some air out the front tyre.

Nice, thanks for reply. With such great detail.
4- stiffer spring will actually make the bike softer in first part of the travel as it will have less preload on spring.
But to your defense i should of said at the same sag setting for your weight

 

[Tim29]

A list of shocks would be good here.

Basically any shock that doesn’t make a clicking sound when you bounce it slightly like doing rebound test. If t has a checked rebound you can audibly hear the valve close.
Pretty much everyone has gone away from it. Unfortunate there a few models that came both with and without a check valve depending on what it was spec for. Unfortunately i can’t give you a list of that, sorry.

 

[njn]

1- rebound clicker what does it affect when you open it several clicks. returns to full extension faster.
2- If i add air to fork how does it affect mid stroke comp and rebound. blows through both faster.
3- If i add a volume spacer how does it work, what affects will it have. increased ramp up at end of stroke, makes the air spring more progressive.
4- coil over -If i install a stiffer coil spring will it make the bike stiffer or softer in first part of the stroke coil springs are typically linear, so stiffer throughout the entire stroke.
5- coil over, will my rebound have any affect with a stiffer spring. yes, may have to go to a higher tune for it to be effective.
6- If i speed up rebound on front forks what will happen on jump loop out, worse case.
7- If i stiffen rear shock comp what will happen on a jump face/ take off bucked forward, worse case.
8- If i speed up front rebound will i put more or less pressure on front tire in turns. less, wheel should recover faster from bumps and follow the terrain better.
10- front end is nervous at speed and feels like i have no traction. What do i do. speed up the rebound and lower the compression to prevent stack up. If the fork is too low in the travel, stiffen the spring.

 

[Tim29]

This is awesome,
But maybe what would be more helpful, instead of a quiz, would be to go through your ten questions and explain the answers to the riders on the forum.
Maybe then have a quiz

I wanted readers input as they see it working, didn’t want to change there way of thinking or sway them from the general consensus of how it works. Once i get he info i need i will post a tuning chart and. Maybe a few dyno graphs on how it all works and explain there affects on the tail.
But keep in mind some people will feel they hveba different affect.
What we have learned is every human has a different firing order.
Meaning there instinct and reaction muscles all fire and different rates and intensity. This is why we have so many different suspension setting and people prefer different settings on same bike and course.
Example your brain and body may fire your forearms then back muscles and finally your legs.
Mine may fire legs arms back. So we both load the bike completely different so we would like totally different settings.

 

[Al Boneta]

I wanted readers input as they see it working, didn’t want to change there way of thinking or sway them from the general consensus of how it works. Once i get he info i need i will post a tuning chart and. Maybe a few dyno graphs on how it all works and explain there affects on the tail.
But keep in mind some people will feel they hveba different affect.
What we have learned is every human has a different firing order.
Meaning there instinct and reaction muscles all fire and different rates and intensity. This is why we have so many different suspension setting and people prefer different settings on same bike and course.
Example your brain and body may fire your forearms then back muscles and finally your legs.
Mine may fire legs arms back. So we both load the bike completely different so we would like totally different settings.

We need a suspension tuning thread and you are the best man for the job.

 

[Tim29]

We need a suspension tuning thread and you are the best man for the job.

Al, once i get info from readers i do something that might be able to help put a lot o people

 

[Dax]

I thought 6-10 were quite interesting, because they made me realise that while I understand the concept of suspension and at least some of the effects of the individual adjustments, I don't understand how they add up to behaviour on the trail. Usually I would only adjust suspension if it feels harsh, is blowing through the travel, bottoming out or spitting me off. If it feels nervous around corners I would assume it's the tyre pressure at fault.

 

[Tim29]

So if you look at the picture, the big heavy red arrow on the shaft is actually indicating the internal needle that opens and closes the bleed port.
The arrow on the side is one of two ports, there another on opposite side.
Then the arrow on the end point at the nut that retains all the valving and piston assy.
So the shaft has a hole from the tip to where the side arrow is and that’s what you call a free bleed. Meaning it allows oil to bypass all the internal valving assembly. This is what your able to adjust with your knob. Open port up and more oil flows through the hole giving you faster rebound.
But it also allows oil to flow faster on compression as well,
It’s also why you can use the rebound adjuster to make your forks feel better on chatter as it allows lighter dampening and adsorbs more of the chowder.
1- volume spacers, they work great for ramping the spring rate and giving users easy quick way to hold the bike up in the stroke and reduce the amount of travel used, but they also cause a balance issue.
Meaning when you add volume spacers your making the spring rate climb fast and your actually using air pressure to keep from blowing through the stroke and not shock dampening. So with a heavy spring you need heavy rebound. Or the fork becomes bouncy in the middle and deep in the stroke as the air spring is very stiff and the rebound is very light. So if i add more then one volume spacer i then go into the fork and add rebound dampening to the valving to control the mid and deep stroke rebound. This way i can keep my rebound adjuster open further and the bike will react to chowder and be super plush in first parts of the stroke but on steep jump faces, rough high G corners, and chunky monkey boondocking the bike doesn’t deflect, bounce, or get loose and tuck front wheel.
Do a test on glass or hard surface table.
Take a empty plastic 99cent water bottle, put one finger on top and press down fairly hard, then slowly try to roll the bottle to one side. Soon as the base of the water bottle looses grip the bottle will shoot off your finger and out from under your hand. Then take the same water bottle and squeeze half the air out of it and do the same test. You find the bottle no longer shoots out but rather just slips.
So when you have high fork pressure or more volume spacers your front end soon as it looses the slightest of traction the forks extend shooting the tire out from under you causing those violent front wheel tucks. ( this why i would ride a ridged huffy over poor setup enduro bike)
Th problem here is 90% maybe more blame this on, the dirt, rider or front tire.
Good suspension can make a shitty tire feel good, and a great tire can help cover up shitty suspension.
This is also why hard tail riders are so much faster through the turns, as they don’t have rear suspension unload when front slips and they don’t have nearly the number of violent front wheel tucks.

 

[Tim29]

Jump face, on some feature enduro/DH courses there seems to be a growing trend to put really steep faces or even kickers. Most riders first exp going off them the find there ass pucker as there front end quickly drops and they feel the slow panic of I’m going over the bars. 90% of the people i see this happen to when i aske then what happen they respond i didn’t pull up hard enough or lean back far enough.
Well not a lot of truth to that. Yes you can do that and prob solve the problem but it’s not the fast easy way!!
1- bike usually to soft in rear, 2- the rear rebound to fast, 3- front rebound to slow.
The way i setup my personal bike i am 2-4ft lower off these jumps then a factory setup bike and that allows me to hit jump fast 5+mph faster and still nail the landing. A lot of these jumps when i pass there pedals are around head high on me and i was going fast enough to go from 1-1/2 bikes behind to past them.

 

[Rob Rides EMTB]

Al, once i get info from readers i do something that might be able to help put a lot o people

This would make an excellent article that could be stickied.

 

[Dusty]

I think an idiots guide to set up your suspension would be beneficial to a suspension idiot like myself .
As everyone's size and weight is different there probably is some generic way of basic set up without being over technical for us mere mortals
Am guessing Terrain will dictate most set ups so this could be a good starting point as reference guide to use out on the trails?

 

[Tim29]

I think an idiots guide to set up your suspension would be beneficial to a suspension idiot like myself .
As everyone's size and weight is different there probably is some generic way of basic set up without being over technical for us mere mortals
Am guessing Terrain will dictate most set ups so this could be a good starting point as reference guide to use out on the trails?

I find once i have my bike dialed the different places, Sumer to winter, it’s just a click here or there.
I say my biggest setup change would be from a steep lipped feature park to a chunky enduro.
I will slow my rear rebound 3-5 clicks in a feature park to keep the bike flying low and flat without needing to feel as to pull the front up. This way i can stay low and turn down on the face that way i can attack the jumps at such higher speed without the sacrifice of hard over jump landings.
But i way the options how much time do i gain staying flat and low, vs how much speed do i loose in the corners? The slow rebound in rear keeps the slack head angle and the bike turns in a little slower.
If i was gonna setup for a race and it had a lot of jumps and sharp turns i would bring the front down to 32-35% sag from my normal 25%.
On a 180 i keep sag at 25 front 35 rear to reduce pedal strikes. But in a DH run not a lot of pedaling in chunk to worry about pedal strikes.
But i usually to lazy to want to do all that sag changes, so just click here there is where i usually stay and compromise.

 

[Tim29]

Suspension is best done in a bracketing format, meaning you narrow it down.
If you change clicks and really notice nothing chances are your bike to far away from ideal setting to make a solid improvement.
But to learn how to make changes don’t make tiny little ones.
Example, find a comfortable jump where your always having to pull up on the bars to keep level flight.
Test the jump, pedal back up and stiffen your rear shock and slow the rebound all the way, ten go of it again half pace and slowly work back to full pace. Then go the other way, full soft and as fast rebound, again go quite slow first few and see how you have to compensate for the two extremes.
Then do the same with the forks.
You find it quite interesting how different the flight path of the bike is.