Help a light rider with his first air forks.

Plyphon

Hiya,

So i'm not the heaviest of guys - 9 stone 8 on a good day.

Forks are RS Revelation RLT, 140mm

To get anywhere near 20% sag (which is 28mm) I have positive chamber at 55psi and negative at 40psi. And ever then I'm probably not hitting that 20% but I haven't tried with gear on yet so it's probably in the ballpark.

Does this seem a bit low to anyone? I know the printed RS figures are way out but this seems a bit extreme.

The initial stroke of the forks seems very hard compared to my previous Recon Silver (coil) forks - is this normal?

Cheers.

edit: btw I am setting the sag via the bike radar approved way of standing in the attack position and measuring how far the o ring moves.

Greer_

Which chamber did you fill first? Positive? It does seem quite low ....

Plyphon

Yea emptied both then Positive to negative, however when adjusting I'd normally do the neg first letting out 5psi at a time.

Greer_

Are they new or second hand?

bartimaeus

And are you in 'the attack position'? If you are just sitting back on the saddle your weight will be over the back wheel, not the front.

Plyphon

Greer_ wrote:

Are they new or second hand?

They are 2nd hand indeed. Could it be service time?


And yup, "attack position" is affirmative.

The Rookie

Worth a service just to be sure. RS are very easy to service.

What is the positive pressure from the RS chart for your weight?

camerauk

If you put more air in the negative side than the positive side it should make the beginning of the stroke softer
so try 55 psi in positive and 65 in negative and see how that goes

Plyphon

camerauk wrote:

If you put more air in the negative side than the positive side it should make the beginning of the stroke softer
so try 55 psi in positive and 65 in negative and see how that goes

are you sure? the RS manual says for a firmer "XC orientated" feel then you up the pressure in the neg, and for a better small bump compliance you do the opposite.... I mean - doesn't hurt to try so I'll give it a shot tomorrow

Greer_

For more small bump compliance you put more in the negative side.

supersonic

Plyphon wrote:

camerauk wrote:

If you put more air in the negative side than the positive side it should make the beginning of the stroke softer
so try 55 psi in positive and 65 in negative and see how that goes

are you sure? the RS manual says for a firmer "XC orientated" feel then you up the pressure in the neg, and for a better small bump compliance you do the opposite.... I mean - doesn't hurt to try so I'll give it a shot tomorrow

More negative air pressure than the positive for a softer feel at the start of the stroke.

Plyphon

Yeah seems I've really outdone myself this time - checked the manual I read it (or remembered it) the wrong way round - cheers guys! Will try adding more negative tomorrow and see if I can't achieve proper sag with a nice feel and not bottomig out dropping off curbs

mrmonkfinger

Start at something like 5 or 10% more in the negative, so about 60psi.

BTW dual air revs are lovely when set up right.

miss notax

Obviously not the case here (hope you get them sorted ) but in my limited experience some forks simply are not set-up for lighter riders.... I had some Marzocchi Bombers on the Kona which I could not get any movement out of. Took practically all the air out of them etc but I really struggled with them - my weight was off the bottom of the weight 'chart'. In the end I got so fed up I sold them and got some nice plush Fox 36's - lovely

Bit peed off with Kona though, it was a ladies specific freeride bike and they put forks on that were not suited to lighter riders. Or are all ladies that want a freeride bike meant to be more 'well built' types?!!! IDIOTS :twisted:

And breathe.....

supersonic

The charts are just guides - if a full air fork, use whatever pressure is necessary to give you the sag is want.

Plyphon

so,

50 positive, 60 negative seems to give me the rough 20% sag i'm after with a plush feel, I reduced the rebound so it doesn't feel like its packing down.

I'll measure again with my kit on before this weekends ride but I think we're sorted!

Cheers all, now to learn how the compression control thingie works....

Greer_

Rebound affects how quickly the fork extends to stop it feeling like a pogo stick, compression damping affects the downstroke.

Plyphon

yeah I like my rebound to be quite quick, thats sorted. never had a fork with compression tho but i'll start with no dampening and if i feel like I falling through the floor every bump i'll start to ramp it up

Plyphon

can someone clarify - the motion control compression damper adjustment only effects the fork when locked out? it has no bearing on how the fork acts when not-locked?

Greer_

Yep, MoCo allows a few cms of travel to try and help the front wheel maintain grip when locked out. It has no effect when it isn't. The TK damper allows no movement at all when locked out. (except blowoff)

Plyphon

And finally the final pieces of the puzzle click into place - thanks Greer_!

supersonic

Sorry, but that is wrong.

Motion Control on this fork is an adjustable compression damper. At one end it is fully open, at the other fully closed, which locks the fork out. You can set it anywhere in the middle, to progressively add damping.. This can prevent fork dive and bob. When locked out, the fork retains about 20mm of travel to aid traction. Note that some Poplocs do not allow you to make this adjustment.

But you also have Floodgate adjust. This is a blow off valve - you can set it so when the fork is locked it only moves on bigger hits. Too little though and the fork may not lock at all. it also has some effect when the MoCo adjuster is about 3/4 shut too.

Turnkey is an on/off lockout with no adjustment inbetween. The blowoff valve is fixed, but the fork is still designed to move slightly for traction.

mrmonkfinger

supersonic wrote:

But you also have Floodgate adjust. This is a blow off valve - you can set it so when the fork is locked it only moves on bigger hits.

I always thought this worked in exactly the same way to ProPedal or SPV - is that right?

supersonic

It can be adjusted to set it up the same, yes.

Plyphon

I see that now - I don't seem to be able to set my lockout at anywhere other than fully open or fully closed - this is with a remote - something wrong or?

Edit: I now see "Note that some Poplocs do not allow you to make this adjustment." - myth busted!

mrmonkfinger

supersonic wrote:

It can be adjusted to set it up the same, yes.

thought so - ta