Bottomless Tokens

JGTR

POAH wrote:

however, running it softer will mean more brake dive so its a trade off. when tuning my pikes I started off at 30% sag but while it was soft it bottomed out so put a couple of tokens in which solved the bottoming out but it had significant brake dive. Adding LSC helped but removed small bump sensitivity. I increased pressure and removed a token and the LSC making the fork much better. Couldn't tell you the sag though. Will need to retune it now I'm on a hard tail

LSC????

Antm81

JGTR wrote:

POAH wrote:

however, running it softer will mean more brake dive so its a trade off. when tuning my pikes I started off at 30% sag but while it was soft it bottomed out so put a couple of tokens in which solved the bottoming out but it had significant brake dive. Adding LSC helped but removed small bump sensitivity. I increased pressure and removed a token and the LSC making the fork much better. Couldn't tell you the sag though. Will need to retune it now I'm on a hard tail

LSC????

Low speed compression

Clockworkmark31

All of the above makes sense, so if the damper can take care of it all then why do flagship forks use tokens instead of sorting the damper out?

rockmonkeysc

Damping has a different effect. Air springs have no damping and need dampers to control the speed they move at. Using damping adjustment you can slow the compression of the fork to stop it bottoming but too much damping will make the fork (or shock) unresponsive and harsh.
Ideally you want to be able to adjust spring rates, spring progression and damping.

Clockworkmark31

Ok think I have it now,

So the tokens just basically alter the speed of compression and the damper is used to exploit that, ie speed or slow it up?

rockmonkeysc

Clockworkmark31 wrote:

Ok think I have it now,

So the tokens just basically alter the speed of compression and the damper is used to exploit that, ie speed or slow it up?

No the tokens alter the spring rate curve. They won't effect the speed at which the spring compresses but increase the spring stiffness deeper in the travel.
A linear spring with a rate of 1kN/mm will compress one millimetre for every kN of force applied.
Reducing the volume makes the spring more progressive so while it might still take 1kN to compress 1mm at the start of the travel it could ramp up to say 4kN at the end of the travel.
Damping converts the potential energy (or kinetic energy of moving spring depending on how you look at it) in the compressed spring to heat energy which has the effect of slowing it's motion.

Clockworkmark31

So they give an exponential curve to the travel? The more you compress the harder it will become to compress, alter the tokens and you can alter the curve. And the damper acts as a resistor to this?

rockmonkeysc

Yes

The Rookie

As a thought provoker, the tokens are great for making a fork suitable for riding bigger terrain, so where for example a normal 100mm fork will either be too stiff or dive through its travel at a trail centre like Cannock where circa 120-130mm is probably what you need (would choose), by using Tokens you keep the initial spring rate the same (whatever you do it will always be the same as the pressure when sagged multiplied by the piston area has to equal the force applied by the weight it is holding up) but stop it diving through it's travel so readily maintaining control (you lose suspension control if it bottoms out).

The modern trend for bigger hitting mid travel bikes (like the Mega and Scout) means the tokens are coming into their own so they can cope with the bigger loads these bikes you encourage you to put them through.

JGTR

I needed tokens just to be able to ride on any terrain. Seems an issue specific to the 29" Rebas.

rockmonkeysc

The Rookie wrote:

As a thought provoker, the tokens are great for making a fork suitable for riding bigger terrain, so where for example a normal 100mm fork will either be too stiff or dive through its travel at a trail centre like Cannock where circa 120-130mm is probably what you need (would choose), by using Tokens you keep the initial spring rate the same (whatever you do it will always be the same as the pressure when sagged multiplied by the piston area has to equal the force applied by the weight it is holding up) but stop it diving through it's travel so readily maintaining control (you lose suspension control if it bottoms out).

The modern trend for bigger hitting mid travel bikes (like the Mega and Scout) means the tokens are coming into their own so they can cope with the bigger loads these bikes you encourage you to put them through.

The hard hitting short travel bikes generally have a 140mm+ fork and are best suited to stiffer forks like the Pike, Fox 36 or Marzocchi 350 rather than Revs or Rebas.
Shorter travel forks with 32mm stanchions have quite small air chambers and are usually quite progressive anyway. I think people often can't get their setup right and see tokens as a miracle cure for everything, then theres the placebo effect of fitting them.

Clockworkmark31

Understood thanks

So I understand now that even if you did change the size of the air chamber it would do b*gger all to my old Foxs.

JGTR

I think people often can't get their setup right and see tokens as a miracle cure for everything

But you still have to set your fork up whether you have tokens or not so your point is doesn't really make sense???

rockmonkeysc

JGTR wrote:

I think people often can't get their setup right and see tokens as a miracle cure for everything

But you still have to set your fork up whether you have tokens or not so your point is doesn't really make sense???

People often use them instead of setting compression damping properly thinking it does the same thing.

The Rookie

RockmonkeySC wrote:

The Rookie wrote:

As a thought provoker, the tokens are great for making a fork suitable for riding bigger terrain, so where for example a normal 100mm fork will either be too stiff or dive through its travel at a trail centre like Cannock where circa 120-130mm is probably what you need (would choose), by using Tokens you keep the initial spring rate the same (whatever you do it will always be the same as the pressure when sagged multiplied by the piston area has to equal the force applied by the weight it is holding up) but stop it diving through it's travel so readily maintaining control (you lose suspension control if it bottoms out).

The modern trend for bigger hitting mid travel bikes (like the Mega and Scout) means the tokens are coming into their own so they can cope with the bigger loads these bikes you encourage you to put them through.

The hard hitting short travel bikes generally have a 140mm+ fork and are best suited to stiffer forks like the Pike, Fox 36 or Marzocchi 350 rather than Revs or Rebas.
Shorter travel forks with 32mm stanchions have quite small air chambers and are usually quite progressive anyway. I think people often can't get their setup right and see tokens as a miracle cure for everything, then theres the placebo effect of fitting them.

Not sure what you mean by the first part, Tokens are availble fro Pikes as well.....

I agree with them being used as a substitute for setup, that said I'm looking at getting tokens for my SID as the pressure I need to stop it bottoming at Cannock (as an example) ruins the small bump feel, not helped in my case by the lousy Race compression damper (which is also to be replaced when I find something at the right price).