Help a light rider with his first air forks.

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Plyphon
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Help a light rider with his first air forks.

Postby Plyphon » Mon Dec 10, 2012 20:02 pm

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.

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Greer_
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Re: Help a light rider with his first air forks.

Postby Greer_ » Mon Dec 10, 2012 20:09 pm

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

Plyphon
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Re: Help a light rider with his first air forks.

Postby Plyphon » Mon Dec 10, 2012 20:10 pm

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

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Greer_
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Re: Help a light rider with his first air forks.

Postby Greer_ » Mon Dec 10, 2012 20:21 pm

Are they new or second hand?

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Bartimaeus
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Re: Help a light rider with his first air forks.

Postby Bartimaeus » Mon Dec 10, 2012 20:42 pm

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
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Re: Help a light rider with his first air forks.

Postby Plyphon » Mon Dec 10, 2012 21:19 pm

Greer_ wrote:Are they new or second hand?



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


And yup, "attack position" is affirmative.

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The Rookie
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Re: Help a light rider with his first air forks.

Postby The Rookie » Mon Dec 10, 2012 21:35 pm

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?

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camerauk
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Re: Help a light rider with his first air forks.

Postby camerauk » Mon Dec 10, 2012 21:40 pm

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
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Plyphon
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Re: Help a light rider with his first air forks.

Postby Plyphon » Mon Dec 10, 2012 23:12 pm

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 :)

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Greer_
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Re: Help a light rider with his first air forks.

Postby Greer_ » Mon Dec 10, 2012 23:21 pm

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

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supersonic
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Re: Help a light rider with his first air forks.

Postby supersonic » Mon Dec 10, 2012 23:32 pm

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
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Re: Help a light rider with his first air forks.

Postby Plyphon » Mon Dec 10, 2012 23:52 pm

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 :)

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mrmonkfinger
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Re: Help a light rider with his first air forks.

Postby mrmonkfinger » Tue Dec 11, 2012 12:07 pm

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
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Re: Help a light rider with his first air forks.

Postby miss notax » Tue Dec 11, 2012 13:32 pm

Obviously not the case here (hope you get them sorted :D ) 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 :D

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:

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supersonic
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Re: Help a light rider with his first air forks.

Postby supersonic » Tue Dec 11, 2012 13:52 pm

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

Plyphon
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Re: Help a light rider with his first air forks.

Postby Plyphon » Tue Dec 11, 2012 19:18 pm

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....

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Greer_
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Re: Help a light rider with his first air forks.

Postby Greer_ » Tue Dec 11, 2012 19:32 pm

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

Plyphon
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Re: Help a light rider with his first air forks.

Postby Plyphon » Tue Dec 11, 2012 19:40 pm

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
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Re: Help a light rider with his first air forks.

Postby Plyphon » Tue Dec 11, 2012 20:08 pm

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?

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Greer_
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Re: Help a light rider with his first air forks.

Postby Greer_ » Tue Dec 11, 2012 20:29 pm

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)


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