Dammit I can't...
 

[Closed] Dammit I can't set up my rockshox revs

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Got some new rockshox revs on the bike. The fork is supposed to have low sp compression damping but the dial that controls it is fastened to a pop loc, and is either fully open or locked. The online guide suggests the compression damping can be changed dialled so what am I doing wrong?

Cheers
rich


 
Posted : 17/06/2010 5:05 pm
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On mine, there's a blue knob on the poploc lever - that controls compression damping when 'unlocked'.

Compression when locked is governed by a tiny allen key under the brass knob on the top of the damper leg.


 
Posted : 17/06/2010 5:09 pm
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I thought the idea was to lockout the compression and use the floodgate to control low speed bump threshold?


 
Posted : 17/06/2010 5:19 pm
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Well for lockout, yes. But I think the OP was talking about compression when riding, no?


 
Posted : 17/06/2010 6:02 pm
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My revs confuse me! I think I'm going to take off the on-of handlebar lever thingy and change it for a fork top adjuster


 
Posted : 17/06/2010 6:04 pm
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What's confusing about it?

Blue knob on handlebar is compression damping. Flick the lever for lockout.

Simples.


 
Posted : 17/06/2010 6:14 pm
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Having leg-top adjustment doesn't make much difference. It's basically just the same but further from your hand. I only ever flick mine fully open or fully closed, and even then, not that often.


 
Posted : 17/06/2010 6:18 pm
 ton
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i too am having trouble with my new revs.
the lockout is not locking them out.

i know it does not lockout totaly but with the compression dial all the way to + or - it is just the same.

the cable is nice and tight and i have used 5 sets or revs in the past, and never had this problem.

how hard is it to fit a fork leg type lockout knob?


 
Posted : 17/06/2010 6:20 pm
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I think PP had a guide for it. You just need the knob and then to disconnect the return spring for the lockout iirc.


 
Posted : 17/06/2010 6:28 pm
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Right. How locked out the lockout gets is dictated by the brass knob on top of the leg marked 'gate'. On mine, at least.


 
Posted : 17/06/2010 6:58 pm
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How locked out the lockout gets is dictated by the brass knob on top of the leg marked 'gate'

nope. maybe not so simples 😆

the flood gate adjuster determines the size of the force required to override the compression damping.


 
Posted : 17/06/2010 7:13 pm
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... but only when locked (right?).


 
Posted : 17/06/2010 7:20 pm
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...if you have the crappy bar lever as they only do on or off. If you have the fork top dial, floodgate overrides whatever compression setting you decide to use.

Or so I'm led to believe by my friend who works in the service dept at Madison. I don'y think anyone really knows how they are suppoosed to be set up!


 
Posted : 17/06/2010 7:24 pm
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Right, the floodgate only has an affect if the compression is locked-out.

I've just got a set of revs myself and been playing around with the setup, running them with compression locked out and a very light floodgate (4 clicks from -). Seems to work pretty well.


 
Posted : 17/06/2010 7:32 pm
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Right, the floodgate only has an affect if the compression is locked-out.

no, that's not true

Or so I'm led to believe by my friend who works in the service dept at Madison. I don'y think anyone really knows how they are suppoosed to be set up!

Kapusta does:

http://forums.mtbr.com/showpost.php?p=1498056&postcount=13

I run his '2' settings. Works really well


 
Posted : 17/06/2010 8:10 pm
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The lockout simply puts 100% compression damping - with a blowoff if you hit a really big bump. The level at which the blowoff activates is adjustable.

this is not the same as adjusting compression damping.

Teh floodgate only comes into play if the lockout is on.


 
Posted : 17/06/2010 8:15 pm
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That's not how mine work, TJ. When the lockout is on, and the gate is adjusted, they do move when locked out but very slowly ie lots of damping. Not the same as a blowoff afaik.

I have them set to move a reasonable amount when the lever's pressed, so that I can use it on say steep drops and they won't dive and chuck me over the bars. Although I know there is another adjuster in there somewhere that I've not played with yet.


 
Posted : 17/06/2010 8:57 pm
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Blue knob only does anything when cable is tight on mine. I think.


 
Posted : 17/06/2010 9:03 pm
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I have 2 sets and thats how mine work - one with an adjustable blowoff and one without.

Mind yo I never use them anyway. I have no need.


 
Posted : 17/06/2010 9:04 pm
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Yes, cos all the blue knob does is wind in the cable a little bit...

TJ - does the lever flick back when you hit a bump?


 
Posted : 17/06/2010 9:12 pm
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Not on mine molgrips.


 
Posted : 17/06/2010 9:14 pm
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What, the blue knob doesn't wind in cable?


 
Posted : 17/06/2010 9:16 pm
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I can't set up the dual air properly 😛


 
Posted : 17/06/2010 9:16 pm
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nope molgrips - the cable / lever pulls the poploc on locking out the fork by maxing out the compression damping. Teh blue knob adjusts the blowoff that lets the fork move if it hits a big bump.

the lever is either on or off - the blue knob adjusts the blowoff valve

Teh blue knob has no effect on the cable at all. It is a totally separate mechanism adjusting a blow off valve. The blow off valve only comes into play when the lockout has maxed out the compression damping


 
Posted : 17/06/2010 9:18 pm
 ton
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i am gonna go back to full rigid, sick of fettling bike.

infact bikes are rubbish, i am gonna start playing darts............ 8)


 
Posted : 17/06/2010 9:21 pm
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Edit - I think there may be quite a variation in specifications

In the 'Lock' position, the Motion Control limits the fork to a small amount of controlled fork movement. This small amount
of movement enables the front tire to continue to track the terrain without deflecting off obstacles. To set your fork to the
'Lock' position:
• Crown mounted - rotate the blue compression adjuster knob fully clockwise.
• Remote equipped - press forward on the PopLoc or PushLoc lever located on the handlebar.
Floodgate Adjustment (Fig. 4)
Some forks with Motion Control damping allow for fine-tuning of the 'Lock' setting. You can choose the point at which the
'Lock' setting can 'blow-off' and respond to inputs such as bumps or rocks. This adjustment is made by the Floodgate
and is either adjusted internally with a 2.5 mm hex wrench or externally with the gold 'Gate' adjuster knob.
When in the 'Lock' position, the maximum (+) Floodgate setting results in a fork with the most limited movement,
while the minimum Floodgate setting results in a fork with slightly limited movement. Heavier riders may find better
performance with maximum Floodgate settings, while lighter riders may find better performance with minimum Floodgate
settings. With the Floodgate tuned properly, the Motion Control will resist rider induced "bob" but provide compliance to
medium sized bumps in rough or aggressive terrain. You should experiment with the Floodgate settings while on the trail
to optimize the fork for your riding style.
the floodgate is intended to adjust the blow-off threshold while in the 'lock' setting only. ensure the motion control
system is set to 'lock' before adjusting the floodgate. for crown mounted adjusters, hold the blue compression
adjuster knob in the 'lock' position while adjusting the internal floodgate.
for maximum fork movement and compliance return the fork to the 'open' position.


 
Posted : 17/06/2010 9:26 pm
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To me, blow-off means that the lockout is released completely when you hit a big bump. That's not what my forks do. The lever just increases the damping a lot.

Also on mine, the blue knob is on the bar-mounted lever, and it does just adjust the cable - there's nothing else linking it to the fork, sot hat's all it has to do.

I suspect your forks are different to mine.

EDIT: having re-read that, TJ, rockshox idea of blow-off is also different to mine 🙂


 
Posted : 17/06/2010 9:28 pm
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TandemJeremy - Member
this is not the same as adjusting compression damping.

Teh floodgate only comes into play if the lockout is on.

just not true


 
Posted : 17/06/2010 9:36 pm
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retro - it is true on my forks. Without the lockout on the floodgate is irrelevant. Read the link to the manual.

Lockout / poloc off then you have minimal compression damping annd the blow off / floodgate has no effect. It can only come into play once the lockout / poplock

RTFM

the floodgate is intended to adjust the blow-off threshold while in the 'lock' setting only

Molgrips - yours is obviously a different set up. There seems to be more variations than I thought. Mine the adjustment is on the fork leg


 
Posted : 17/06/2010 10:13 pm
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Molgrips we are on about a different blue knob.

TJ's is as mine. There must be differing models. Or some folk here are numpties.


 
Posted : 17/06/2010 10:16 pm
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TandemJeremy - Member
retro - it is true on my forks. Without the lockout on the floodgate is irrelevant. Read the link to the manual.

Lockout / poloc off then you have minimal compression damping annd the blow off / floodgate has no effect. It can only come into play once the lockout / poplock

RTFM

the floodgate is intended to adjust the blow-off threshold while in the 'lock' setting only

The manual is wrong. Plainly obvious in usage, and if you open them up and have a close look at the damper it's clear why this is the case.

Lockout / poloc off then you have minimal compression damping annd the blow off / floodgate has no effect. It can only come into play once the lockout / poplock

You have the normal Poploc, there is also one which allows the compression to be set to any position between fully open and almost closed.
I think this is called the "poploc adjust" I believe this is what molgrips is talking about:
[img] [/img]


 
Posted : 17/06/2010 10:18 pm
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So how do you alter the compression without Spanking £60 on the remote-with-blue-dial, with the lockout off? Sounds like you can't. Maybe reducing negative air pressure? Is there anyone out there with 'the knowledge'?


 
Posted : 17/06/2010 10:56 pm
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You can't. ( unless there is an internal adjuster which I think some have)

I don't know why you would want to alter compression damping anyway. The more you have the less responsive the fork is. Air pressure only affects spring rate.

First set sag to 25% or so using the air pressures. Then set rebound damping to suit - usually the least that you can have without the fork being bouncy. Then ride.


 
Posted : 17/06/2010 11:06 pm
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rnewell1973 - Member
So how do you alter the compression without Spanking £60 on the remote-with-blue-dial, with the lockout off?

you can use a thumb shifter in friction mode, or get one from Merlin - they occasionally do them on ebay for £25

TandemJeremy - Member
You can't. ( unless there is an internal adjuster which I think some have)

I don't know why you would want to alter compression damping anyway. The more you have the less responsive the fork is.

Because you can control fork movement without affecting the spring rate. You then set the floodgate sufficiently soft to open up when needed and prevent the fork spiking.
I like this because it stops the fork compressing too much during hard cornering, or on slow techy descents and changing the head angle too much.

I have my LSC (blue dial) set to about 60% and the floodgate set to about 7 clicks from fully open. Personally I really like MoCo setup this way, PUSH'd MoCo with this is even better. So much more composed at speed


 
Posted : 18/06/2010 7:45 am
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you can use a thumb shifter in friction mode

I am starting to wish i had kept my coil pikes rather than getting some new revs off Merlin now...all seems very complicated.


 
Posted : 18/06/2010 8:36 am
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Retro83 - that's what I have, yes 🙂

TJ - compression damping is so that you don't blow through all the travel on big hits. The bigger hits you are expecting, the more compression damping you need. It also helps to stop the fork diving too much on steep drops and steps. The people who run the most compression damping are dirt jumpers or freeriders throwing themselves off cliffs. Increasing the spring rate would also help this but the fork would then be rock hard in normal riding.


 
Posted : 18/06/2010 8:53 am
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So how do you alter the compression without Spanking £60 on the remote-with-blue-dial, with the lockout off? Sounds like you can't. Maybe reducing negative air pressure? Is there anyone out there with 'the knowledge'?

If you have no remote, just a fork top lever dial, compression can be adjusted by not turning that lever all the way round. It has nearly 1/2 a turn from fully open to fully on. Roughly speaking, the first half of the movement available controls compression in small incremenets, then after that you're into lockout territory. The thing is, as soon as you lock the fork out, you've moved the dial from your chosen compression setting and you've got to find that setting again when tou unlock the fork

This is how the Poploc Adjust in the pic above works: The lever pulls the cable all the way and activates the lock out to whatever level is set by the Floodgate Adjust (Small screw/knob in the centre of the fork top) but the blue dial on the lockout remote lever just pulls the cable a small amount and holds it there, to adjust compresstion. When you unlock the fork, the lever returns the cable to the level set by said blue dial, effecively 'remembering' your chosen compression setting.

Phew!

That said, personally I never thought the compression adjustment range was much good, or really did much, and I only think a bar mounted lock out lever is much use on a singlespeed or for racers. Which is why I converted mine to a fork top dial.

Does any of that help, or indeed, make any sense?
🙂

EDIT
Reducing negative air can be a good idea. It makes the action more progressive and stops the fork blowing through it's travel too easily. Especially usefull for steep stuff or jumping. It's better to do that than to increase compression damping, which just results in an unresponsive fork 🙂


 
Posted : 18/06/2010 9:08 am
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I am starting to wish i had kept my coil pikes rather than getting some new revs off Merlin now...all seems very complicated.

It doesn't matter what spring you've got (Air or coil) the damping still works exactly the same. 🙂


 
Posted : 18/06/2010 9:10 am
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I am confused. I have the remote switch but don't use it, I just keep the damping "on" with a cable tie. The blue knob at the crown adjusts floodgate but not really compression.


 
Posted : 18/06/2010 9:12 am
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Al, do you mean that the bar lever is pushed in all the time, or that you haven't fitted the lever at all?

EDIT
Where exactly is your cable tie?

I'm trying to work out what you're doing, so I can maybe help out 🙂


 
Posted : 18/06/2010 9:13 am
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As an aside, I reckon RS forks are too adjustable, too complicated for most people. They are a faffers delight, but there's so much BS and mis-information around about how they work, it just confuses people. I worked it out for myself.....

My advice? Get Vanilla Rs instead: Hardly anything to adjust at all, so you can't get it wrong. That's what I have on my bike. 🙂


 
Posted : 18/06/2010 9:17 am
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PeterPoddy:
It doesn't matter what spring you've got (Air or coil) the damping still works exactly the same

I meant in as much as I had crown adjustment on the pikes rather than just an on/off lever like i have on my new revs. Might try and source a second hand poploc with adjuster off the classifieds.

...or failing that how much would you want to install the [url= http://www.tftunedshox.com/catalogue/image.aspx?img_id=435318f7-9469-4ce2-b59e-9c2000eed0db ]crown adjuster[/url] Peter? 😉


 
Posted : 18/06/2010 9:23 am
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PP - the zip tie is at the crown, replacing the cable and holding the damping in the "on" position.


 
Posted : 18/06/2010 9:28 am
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As an aside, I reckon RS forks are too adjustable, too complicated for most people. They are a faffers delight, but there's so much BS and mis-information around about how they work, it just confuses people.

Sounds about right from what ive just read...

However I do have a setup question, I have always been of the opinion if you got your spring rate right, be it coil or air, that really you dont really need to have any compresion damping on.. Right or wrong?


 
Posted : 18/06/2010 9:36 am
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replacing the cable and holding the damping in the "on" position.

OK, that's roughly what I thought. Not taking the pee, but what's your reasoning behind this?

I'm assuming the dial will spring open if you remove the cable tie. If you want to be able to adjust the compression a bit and still use the lokout as intended, you need to release the spring inside the Motion Contol unit. It's best to fit a proper crown mounted dial/lever as well (Because it's easier to see where it's set, and easier to use), but it'll work just the same with the cable pulley.

[url= https://docs.google.com/fileview?id=0B1AoGIWBz4H1YWNhYWRkODYtNzRiNi00YTA1LTlmMjctNmQzOWQwMDdiZGFl&hl=en ]CLICKY![/url]


 
Posted : 18/06/2010 9:47 am
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However I do have a setup question, I have always been of the opinion if you got your spring rate right, be it coil or air, that really you dont really need to have any compresion damping on.. Right or wrong?

How long is a peice of string?

To a certain extent I agree, yes, that's the correct way to go about it:

A good spring rate is waaaaaaaaaaay better then trying to prop the fork up with more compression damping, and 95% of the time on the RS forks I've owned, I've run compression at minimum to be fair.

But some people like to slow the compression a bit for whatever reason, which is fine. Others people get carried away and I disagree with trying to compensate for crap set up with more damping. But that's just me.

Get your spring rate spot on and everything else is secondary. 🙂

(And rebound is more important than compression, but can we not go into that right now please? 🙂 )


 
Posted : 18/06/2010 9:53 am
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Ah well - having set my spring rate, oil levels and weights and damping correctly I have no need for the lockout so all my forks with poploc have had the lever removed if remote or ignored if fork top.

I have no issues with excessive dive nor with bob. I get full travel , good small bump sensitivity and a plush ride.


 
Posted : 18/06/2010 10:21 am
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Ok folks, listen up. The revs are not at all complciated really.

There's two settings - normal, and 'locked', via the lever. Compression damping in normal mode is set by the blue knob on the lever, and how 'locked' it is when you flick the lever is set via the brass knob on the fork. Simple.

I have always been of the opinion if you got your spring rate right, be it coil or air, that really you dont really need to have any compresion damping on.. Right or wrong?

Wrong. Imagine riding along on a flat piece of road, and then you hit a rock. If you had no compression damping, the wheel would rise up and swallow the rock, and you'd carry on. But what if the rock is bigger than 140mm? You'd bottom the fork out with a hell of a slam, hitting the rock effectively with no suspension at all. Compression damping is there to slow the fork down, so that when you hit a big rock you still have some travel left to work.

Some forks have not much damping in the first part of the stroke, but it ramps up as you compress the fork.

PP, if you think damping is not important, empty the oil out of your forks and go ride something rocky. And film the results, I could do with a laugh. You ride your forks on minimum damping, that's fine, but it's still damped!

Setting spring rate is the easiest thing in most forks, especially ones with a single chamber like my Revs - 25% sag and off you go. So if your forks are badly set up it's not the spring rate that's the problem. Damping is the key.


 
Posted : 18/06/2010 10:21 am
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Wrong. Imagine riding along on a flat piece of road, and then you hit a rock. If you had no compression damping, the wheel would rise up and swallow the rock, and you'd carry on. But what if the rock is bigger than 140mm? You'd bottom the fork out with a hell of a slam, hitting the rock effectively with no suspension at all. Compression damping is there to slow the fork down, so that when you hit a big rock you still have some travel left to work.

Some forks have not much damping in the first part of the stroke, but it ramps up as you compress the fork.

PP, if you think damping is not important, empty the oil out of your forks and go ride something rocky. And film the results, I could do with a laugh. You ride your forks on minimum damping, that's fine, but it's still damped!

Point missed, matey. You need to read what I type!

Me -
[i]I've run compression at minimum to be fair. [/i]

By that I mean the damping is set to minimum. It's very easy to understand! NOT that I [i]don't have any damping[/i]

As long as there's oil in the forks, no matter what you do with the adjusters, you've got damping. Fact.

And your +140mm rock theory doesn't work either. Even if you did have no damping AT ALL, no oil in the leg, the tension of the spring will still perform a rudimentary compression daming effect. What you WON'T have is any REBOUND damping to slow the return of the spring, so it'll extend at maximum speed and feel very pogo-stick-like!
Which is why I wrote [i]"rebound is more important than compression"[/i]
Because it's more important to have control of rebound adjustment than compression

And this bit -
[i]PP, if you think damping is not important[/i]

Shows you really have tken some words I've typed, added some more random ones, shaken them about a bit, and then read them! Because nowhere did I say that! 🙂

Go back and read again my child, because you're coming up with more of this BS and mis-information I refered to earlier, mostly because you've not taken the time to read and understand..... 🙂


 
Posted : 18/06/2010 10:30 am
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Setting spring rate is the easiest thing in most forks, especially ones with a single chamber like my Revs - 25% sag and off you go. So if your forks are badly set up it's not the spring rate that's the problem. Damping is the key.

*Cough* Revs have 2 chambers: +ve & -ve *cough*

And you're wrong. Spring rate is more important. Change to 50% sag or 5% sag and see if it's not.....

Spring rate is what you set FIRST with any series adjustments.
Then damping after that.
Why?
Because a different spring rate requires different damping settings to control it properly, for a given weight of rider.
Simples. 🙂


 
Posted : 18/06/2010 10:40 am
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PP I hate handlebar clutter and never bother switching lockout/damping on/off. I like a little lockout though to stop bobbing and diving.

The blue dial on the lever only adjusts how far the cable is pulled when you puch that lever - therefore gives a % of lockout rather than full lockout IIRC.


 
Posted : 18/06/2010 10:40 am
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all this thread demostrates to me is how little many folk understand how to set up suspension. PP is pretty good with this stuff - listen to him if you don't want to listen to me.

Cynic al - correct


 
Posted : 18/06/2010 10:44 am
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Easy now PP. The story with the rock was aimed at Tinsy, hence the tinsy quote at the beginning of it. I was explaining why we have compression damping. And it is a valid point. If there was no damping and you hit a 145mm rock you might get away with it, but then when you hit another 30mm rock immediately afterwards you'd be in serious poo. Even more so if you are say riding through a trough on a downhill - you'd be over the bars before you can say 'Argh I should've listened to Molgrips and his clear and concise explanations!' 😉 You might get away with one rock if you had no oil in your forks because there is intrinsic frictino based damping in the fork seals and whatnot.

But please note the above (and most of the original post) is aimed at answering Tinsy's reasonable question about why we need compression damping. So we all need to read posts carefully, don't we? 🙂

I have fully read and understood your post PP, I don't get why you are dishing out aggro to me. I am merely after a cheerful Friday morning chat, I don't want to be slagged off... If I may be allowed to make my point a little more competently than I did last time, I believe that damping is equally important to spring rate, not secondary to it. As anyone who's lost damping on a ride should be able to testify.

TJ - some of us like to adjust damping on a ride for a variety of reasons. One is for road sections - I rode hard home with my bike mostly locked out (despite having been not keen on the idea in principle) last night and it made it more fun and entertaining I think - felt a lot more positive when doing the urban warrior thing. Also, as mentioned above, with the adjustable rate motion control thing on RS, you effectively have two modes available at the flick of a lever - one for normal riding and one with lots of compression damping for say tricky steep bits. Not essential, but nice. I like to examine all the possibilities that my equipment gives me, which is why I have gone for this setup.


 
Posted : 18/06/2010 10:47 am
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Molgirps - Sorry if it came over the wrong way, it was menant to be slightly light hearted, hence the smileys. Apologies if I sound a bit blunt! 😳


 
Posted : 18/06/2010 10:50 am
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molgrips - but you don't understand what the various things do - hence you seem to think that compression damping does something it does not.

If there was no damping and you hit a 145mm rock you might get away with it, but then when you hit another 30mm rock immediately afterwards you'd be in serious poo.

Is just complete rubbish. if you have no damping at all the fork will just bounce up and down - what you need in that instance is not much rebound damping to stop it packing down and minimal / zero compression damping to allow the fork to adsorb the bumps. All having a lot of compression damping will do is prevent the fork from absorbing the bumps. You might as well have a rigid fork or a 60 mm travel one.

Get your fork set up properly and you don't need the lockout unless you are a low cadence stand up on the pedal rider when it might be useful to prevent bob.


 
Posted : 18/06/2010 10:56 am
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TJ, you clearly don't understand damping, and we know from experience that it's IMPOSSIBLE to get you to change your mind, so I'm gonna leave it, with one final thought: Why do you think suspension designers (car, bike, motorbike etc) give you the option to change and tune your damping, and why do so many expert riders/racers/technicians spend so long tuning it?

Actually no, don't answer that. Never mind.


 
Posted : 18/06/2010 11:02 am
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Merlin ones here aswell, pushloc works fine but they blow through the travel pretty quick. Sag is Ok but too easy to get full travel, more air to stop blowing through travel = 10% sag ffs. Can I put heavier oil in?

Suppose I coudl bodge the cable so the are alway on *a bit * damped with blue dial.


 
Posted : 18/06/2010 11:05 am
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Molgrips - I have been adjusting and setting up suspension on motorcycles as well as bicycles for decades including stripping and rebuilding dampers to my own spec. I have read widely round the subject. You are confusing rebound and compression damping. Of course tuning your damping is very important. its just you are confused about what adjustments do what - as are most folk.

Edit - motorcycles back in the 80s used compression damping lockouts activated from the brakes ( antidive) soon discarded as a useless idea as locking out your fork stops the suspension from working


 
Posted : 18/06/2010 11:07 am
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Why do you think suspension designers (car, bike, motorbike etc) give you the option to change and tune your damping

And if you work up from the bottom of the range, why is the first damping adjustment that becaomes availble always [i]rebound[/i] damping? 🙂

And that certainly applies to motorbikes as well as MTBs......


 
Posted : 18/06/2010 11:11 am
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TJ I know exactly the difference between rebound and compression damping, I'm not the retard you think I am 🙂

And you can bang on about motorbikes all you like, most of them are ridden on surfaces that are very consistent ie road.

I understand the requirements of MTB damping to a fair extent, so I'll continue to tune my bike the way I like it, and analyse the results and adjust where necessary.

In any case - you said 'I don't know why anyone would want to adjust compression damping on the fly', and I am telling you why I like this ability. Why on earth did you then start telling me how wrong I am?


 
Posted : 18/06/2010 11:34 am
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Sag is Ok but too easy to get full travel, more air to stop blowing through travel = 10% sag ffs. Can I put heavier oil in?

You do not need heavier oil. Your compression damping is not important. It is all in your imagination. TJ knows best!

(In reality, does sound like you need a bit more compression - heavier oil can work but bodging the cable is a good idea. If you were feeling brave you could tap the cable stop hole on the fork or the lever and fit a barrel adjuster off a mech, that would be an DIY compression adjust knob)


 
Posted : 18/06/2010 11:37 am
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Molgrips - I tell you you are wrong because the example you gave about compression damping and hitting large rocks is simply incorrect. What you described is the behaviour with too much rebound damping "pack down"

You were the first one to mention motorcycles.


 
Posted : 18/06/2010 11:46 am
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Sag is Ok but too easy to get full travel, more air to stop blowing through travel = 10% sag ffs. Can I put heavier oil in?

What forks are these? Rockshox?

If so, I'd hazzard a guess that dropping the -ve air pressure to around 10psi lower then your +ve pressure will help. Propping it up with more compression damping will just result in an unresponsive fork, and changing the oil will also affect the rebound.

It's rather hard to do diagnosis like this in the internet, it's a lot easier to DO IT than talk about it.

Your compression damping is not important

Again, you're not paying attention, that's not what he said. 🙂


 
Posted : 18/06/2010 11:47 am
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Propping it up with more compression damping will just result in an unresponsive fork

Not necessarily. You can up the compression damping reasonably without making the fork too unresponsive. Remember, this is an MTB not a limousine, and it's not really worth chasing the ultimate plush ride over small bumps. I am of the opinion that you can put up with small bumps, but what's really important is taking out big hits and controlling dive and bob. I would suggest that, if the lockout cable is affixed to the damper via a grub-screw like mine, to try loosening it off and taking in a bit of cable to give you more compression damping. You might like it 🙂

PP do me a favour, I was clearly taking the mickey with that post! I do read these things carefully, trust me.

TJ - *sigh*.. I am not talking about pack-down, you completely mis-understand my posts. I was talking about what happens when you HIT a series of big bumps, accompanied by a change in gradient too perhaps. Hitting things is where compression damping is important, as I am sure you understand. And I seem to remember you first mentioned motorcycles when citing your years of experience.

Why does everyone on this forum automatically assume everyone else is stupid? I'm a pretty skilled bike mechanic, and I'm also very intelligent, analytical and observant. So when presented with a fork I explore all its options to see how it can help the kind of riding I do, by fettling it and examining how it affects the feel during riding. I've experienced forks blowing through travel too quickly, along with pack-down, bouncing off stuff, too plush of a ride, not enough etc etc. So I do know a little bit about this. I'm sure there are people who know more, but from what you've posted on here TJ you don't appear to be one of them.

The two original questions that sparked this were a) do you need compression damping (asked by Tinsy) and b) why woudl you want to adjust it whilst riding (asked by TJ). I've tried to answer these.

I like to adjust compression damping sometimes whilst riding because the terrain can change dramatically in the kind of riding I do.


 
Posted : 18/06/2010 12:07 pm
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scruff - Member
Merlin ones here aswell, pushloc works fine but they blow through the travel pretty quick. Sag is Ok but too easy to get full travel, more air to stop blowing through travel = 10% sag ffs. Can I put heavier oil in?

Suppose I coudl bodge the cable so the are alway on *a bit * damped with blue dial.

What sort of weight are you scruff? Not ridden my new Revs yet and ideally don't want to be blowing through the full travel!


 
Posted : 18/06/2010 12:14 pm
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*bangs head on wall*

Pack down is what happens when you hit a series of big bumps with too much rebound. If you are using too much travel then you have too low a spring rate. More compression damping will stop it travelling over bumps but you loose all small bump sensitivity.

if you are running out of travel on a series of big bumps then you need a mix of higher spring rate, decreased rebound and increased [b]high speed [/b]compression. ( which is very rarely adjustable)

Using the lockout and blow off valve to control the multiple hits is simply stopping the fork from working and absorbing the bumps.

Downhill forks do not have lockouts . They hit big multiple bumps often. They will run minimal compression damping so as to absorb the bumps.

Teh lockout is to prevent bob when honking uphill in a low cadence


 
Posted : 18/06/2010 12:24 pm
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Why does everyone on this forum automatically assume everyone else is stupid

I'm not. But I know from what I've read here and in other places that there's a lot of misinformation and BS written about suspension in the MTB world. I've seen some truly terrible comments in mags over the years for instance. And that's what I think you've been influenced by. 🙂

Now, if your personal preference is to have a fork set up in a certain way, then fine, fill yer boots! But trying to pass on something to someone else that isn't really correct isn't a good idea really. More misinformation, more confusion. 🙂

Suspension is very simple. Approach it logically and methodically with the right info to hand and it's the work of minutes to sort out. Get confused by BS from 1001 sources and you're screwed.

Not necessarily. You can up the compression damping reasonably without making the fork too unresponsive. Remember, this is an MTB not a limousine, and it's not really worth chasing the ultimate plush ride over small bumps. I am of the opinion that you can put up with small bumps, but what's really important is taking out big hits and controlling dive and bob.

See, that's easily the best bit you've come up with so far. Your preference is for a tauter (Sportier? 😉 ) feeling fork and you're willing to loose some sensitivity for that. Great! And that's not propping it up with compression damping as has been alluded to elsewhere in this thread.
But trying to tell someone it's the right way to set THEIR suspension up is wrong. Because they might not understand your thinking and assume you're trying to stop the dive on a too soft spring with compression damping. Which then confuses them because it then doesn't feel like they think it should. Hence more misinformation, even if you don't intend it 😀

I try and tell people the basic, correct way of doing stuff, and try and help them [i]understand[/i] what the adjustments do, so they can then go about it in a logical way, aware of what they are doing, not just randomy twiddling dials 'because someone says it does so-and-so' 😀


 
Posted : 18/06/2010 12:29 pm
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If you have the choice of low and high speed compression, then you are in a better position because you can tune separately for small trail bumps and big hits. However the revs do not offer this I think. But yes, you are right about needing more damping, and this is what I have been saying all thread.

Using the lockout and blow off valve to control the multiple hits is simply stopping the fork from working and absorbing the bumps.

That's not what I was saying at all. I am using the lockout/blowoff to provide very high compression damping when negotiating very steep step downs and whatnot, where fork dive can tip you over the bars. So it'd only be on for a few seconds.

More compression damping will stop it travelling over bumps but you loose all small bump sensitivity.

Only if you go overboard. A *bit* more compression damping will help with stability and blowing through travel, at the expense of a *bit* more plushness. But as I said, we're not speccing luxury cars here, these are MTBs and we have suspension to tame big hits. I think that stability is more important than perfect small bump plushness.

They will run minimal compression damping so as to absorb the bumps.

I am not a downhiller, but I don't think this is the case. DH courses tend to have lots of large bumps in, so I doubt the riders are interested in small bump compliance. Anyone who rides downhill care to clear this up?


 
Posted : 18/06/2010 12:36 pm
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And that's what I think you've been influenced by.

No mate, I do all my own experiments and reach my own conclusions!

I try and tell people the basic, correct way of doing stuff, and try and help them understand what the adjustments do, so they can then go about it in a logical way, aware of what they are doing, not just randomy twiddling dials 'because someone says it does so-and-so

If you think that's what I'm trying to do, then you are way off the mark!

I suggested Scruff try something based on what I'd do. I know where he rides, and what the terrain's like. He's welcome to try it out and make his own conclusions. That's why I said stuff like 'you might try' or 'if I were you I'd...' My original post was to try and explain the principles behind compression damping.

In scruff's case, he specifically said that his spring was set up correctly because he has the correct amount of sag. Hence the finger being pointed at compression damping. I don't understand why you think I'm being wrong when you do seem to understand the principles the same as I do.


 
Posted : 18/06/2010 12:40 pm
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Downhill forks do not have lockouts . They hit big multiple bumps often. They will run minimal compression damping so as to absorb the bumps.

That is a complete load of ballcocks.

[b]Cynic-al[/b]

The blue dial on the lever only adjusts how far the cable is pulled when you puch that lever - therefore gives a % of lockout rather than full lockout IIRC.
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[b]TandemJeremy - Member[/b]

all this thread demostrates to me is how little many folk understand how to set up suspension. PP is pretty good with this stuff - listen to him if you don't want to listen to me.

Cynic al - correct

No, incorrect. It sets the amount of cable that is pulled in the OPEN position. Why are you posting about something you clearly do not understand?

Edit: I can't be arsed with this.

Read kapusta's post on mtbr i linked to earlier. If you don't use the MoCo properly I don't care but you are missing out on the best feature of these forks.


 
Posted : 18/06/2010 12:42 pm
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LOL. This thread is rather amusing.

Since 90% of the posters clearly don't know how their dampers work, or what the adjusters do, surely the mtb marketing guys are barking up the wrong tree with highly adjustable forks/shocks.
It's just a recipe for suspension that works terribly due to poor set up.


 
Posted : 18/06/2010 12:47 pm
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correct Glenh

On most motorcycles now ( ducatis excepted) the adjuster range is minimal so people cannot get a totally wrong set up no matter how they fiddle. This is precisely because people get so confused over setup


 
Posted : 18/06/2010 12:50 pm
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If you think that's what I'm trying to do, then you are way off the mark!

No, I was telling you what [b]I do[/b]. 🙂

That is a complete load of ballcocks.

No it's not. Downhill forks DO NOT have lockouts, and THEY DO hit big multiple bumps, so at worst it's only 1/3 ballcocks! 😛

Since 90% of the posters clearly don't know how their dampers work, or what the adjusters do

Go on then, crack on! What does it all do then? Who's right and wrong? I'm all ears.... 😀

surely the mtb marketing guys are barking up the wrong tree with highly adjustable forks/shocks.
It's just a recipe for suspension that works terribly due to poor set up.

I do tend to agree with your setiment there though. I challenge anyone to pick fault with my Vanilla Rs! Preload and rebound and that's yer lot! I love 'em! 🙂


 
Posted : 18/06/2010 12:54 pm
 R979
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I'm a pretty skilled bike mechanic, and I'm also very intelligent, analytical and observant.

You forgot to add 'modest' on your little list there.


 
Posted : 18/06/2010 1:02 pm
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TJ, road motorbike analogies are not very useful here due to the vast difference in usage parameters...

You forgot to add 'modest' on your little list there.

🙂

Sometimes you gotta spell it out to TJ...

It seems me, PP and maybe TJ understand how our dampers work.... TJ's problem seems to be understanding what I'm getting at in my answer to his question about why you'd want to change damping on the fly.


 
Posted : 18/06/2010 1:11 pm
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It seems me, PP and maybe TJ understand how our dampers work

We certainly understand what our preferences are and how to adjust what we have to achieve them. 😉


 
Posted : 18/06/2010 1:13 pm
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No it's not. Downhill forks DO NOT have lockouts, and THEY DO hit big multiple bumps, so at worst it's only 1/3 ballcocks!

😆 No I meant the second part of his assertion. But anyhow I think up until recently at least (2008 maybe) that you could buy Boxxers with the regular MoCo damper which could be locked out. Maybe you still can with the MoCo IS. I'm not sure about that though.

So that would make it 100% ballcocks


 
Posted : 18/06/2010 1:13 pm
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We certainly understand what our preferences are

Not the same thing...


 
Posted : 18/06/2010 1:26 pm
 R979
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A picture is worth a thousand words...hopefully that clears everything up once and for all.

[IMG] [/IMG]

EDIT: I know it's a 2011 Fox 32 with the fancy gold coating in the drawing but the principle is the same on a RS rev


 
Posted : 18/06/2010 1:28 pm
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As a layman i am more confused than when i started reading this thread....might just go rigid 8)


 
Posted : 18/06/2010 1:32 pm
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