[mudia.pl]

Does anyone know the proper IFP pressure for Fox RP23 DRCV (2010)? The settings of shock says:
Boost valve tune 200
Velocity tune L
Rebound tune M

My shock is beeing rebuiled and all we need is to set a proper nitrogen chamber pressure (yes, we have all the equipment needed).
As a test we put 300psi, but rebound is a bit to slow.

We don't have enought time to send it to Fox service (it would take about 2 weeks) befor my holiday.

 

[mtbikerTi]

I believe it is 400 PSI.

 

[ktm520]

Boost valve tune = IFP of 200 psi

 

[mudia.pl]

Is it 200 or 400? Right now, having 300 psi, rebound is a bit slow. Does it mean I should increase or decrease pressure? I don't want to pump it too many times to not damage that rubber seal of nitrogen valve.

 

[Scotth72]

The boost valve tune is the ifp pressure. You answered your own question.

 

[ktm520]

200pis is the correct answer. 400psi is for the non boost valve rp shocks. Boost valve shocks vary which is why they label it on the air can.

 

[mtbikerTi]

Yeah I missed the boost valve part in the OP...

 

[ktm520]

How are you testing the reb to come to the conclusion that it is too slow?

 

[mudia.pl]

Thank you all for the answers

How are you testing the reb to come to the conclusion that it is too slow?

I set correct pressure in Air chamber and copmared with the fork reboud speed. Before service is was almost identical (shock rebound was set for about 5-6). With 300 psi even the lowest setting is slower from the fork.

Another question. Before this service pro pedal wasn't exaclty as I'd like it to be. Setting 3 should by more like LO for me. If I set pressure on let's say 225 psi or 250 psi, would it change pro peldal's behavior? Many times I've got to go asphalt and I'd like to have more hard bike's tail.

 

[ktm520]

Another question. Before this service pro pedal wasn't exaclty as I'd like it to be. Setting 3 should by more like LO for me. If I set pressure on let's say 225 psi or 250 psi, would it change pro peldal's behavior? Many times I've got to go asphalt and I'd like to have more hard bike's tail.

Yes, think of it this way, change the bv tune (ifp) shifts the entire damping curve up or down. It's a very easy way to tune a bv shock if you have ifp fill tools. Start with 25 psi. This will have a noticeable effect. How much do you weight? Although, I'd ride it first because the damping could have been degraded before the rebuild.

 

[mudia.pl]

How much do you weight? Although, I'd ride it first because the damping could have been degraded before the rebuild.

About 70kg including my equipment.

One more question. Will my small bump compilance suffer from adding some pressure (200 psi -> 225/250 psi) when pro pedal is off? Or is there any other aspect of shock's work (apart from rebound) that will change after adding pressure?

 

[cadoretteboat]

You can also play with your oil cst.

 

[mudia.pl]

Hi again.
Does anyone know how much oil should be poured into the IPF chamber for this shock? This model has 50mm travel.

 

[cadoretteboat]

Set the depth of piston and fill it up .

 

[ktm520]

Hi again.
Does anyone know how much oil should be poured into the IPF chamber for this shock? This model has 50mm travel.

For a 51mm stroke, the ifp depth is right at 2.25". This is fairly easy to measure and double check. Set depth, close ifp fill port, and fill damper body to the brim with oil. The ifp takes a -209 oring. Highly recommend replacing it, or at a minimum remove, clean, and lube.

 

[cadoretteboat]

@ ktm What o-ring material have you used or test (if you did) ? Fluorocarbon, Nitrile.
Lubing the o-ring with something else than the oil you used is not recommended, because it will contaminate the oil and cause consequences problems like cavitation and other oil degradation. (it's act like a small air particule for snow to happen).
To OP: did you do some ifp pressure test ? and what was your conclusion if you did.

 

[ktm520]

buna 70. I use slick honey on the oring, light coat. It's compatible with shock oil.