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Hi,

I have just purchased a Nukeproof 275 pro with a Rockshox super deluxe shock.

I set sag/ rebound etc and went for a couple of rides and all felt well. I decided to fit a bottomless token to see how this felt and did a little research and fitted this no issues at all.

After riding a trail I decided to take the token back out as I wanted a fresh comparison.

After taking the token Out I re-pressurized the shock and re-set sag. After a mile or so I decided on a whim just to check the pressure again and it seemed to have lost about 20 psi. I pumped it up again and stopped again in about another mile - and again it had lost pressure.

When I got home I depressurized and opened up again just to check and everything looks A-OK. So I pumped back up to 170 psi and within a couple of hours it was down to 100 psi. The weird thing is that when I keep the pump attached it doesn't lose pressure - Not at all. As soon as I release pump the pressure starts to drop.

Someone had a theory about having to charge the negative air chamber but this wouldn't cause the shock to lose air surely?

The shock is brand new on a brand new bike and obviously I'll send back under warranty but if there is a simple fix that would negate me having to send it back to supplier I'd prefer to do that.

Any ideas or thoughts?

Thanks in advance

Neil
 

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sounds like a faulty valve, you need to send back for replacement
 

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You can't check shock pressure by putting the pump on the shock. When you put the pump on, enough air goes into the hose and gauge to lower the pressure significantly. 20 psi is common.

Shock pumps works by creating a seal at the valve before opening the schrader valve. When you put the pump on and the schrader valve is open, air goes into the hose and pump reducing the pressure that was in the shock. When you pump up the shock, it has the pressure indicated on the gauge. When you disconnect the pump, the schrader valve closes before air escapes the the hose and pump so that the shock remains at the pressure you set.
 

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If you really want to use the pump to check the pressure the thread on the pump enough that the connection holds pressure but have not yet depressed the valve then pump up to the pressure that you think is in the shock, next fully engage the pump then you can see if you have more or less pressure than what you think you had.
 

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Hi,

I have just purchased a Nukeproof 275 pro with a Rockshox super deluxe shock.

I set sag/ rebound etc and went for a couple of rides and all felt well. I decided to fit a bottomless token to see how this felt and did a little research and fitted this no issues at all.

After riding a trail I decided to take the token back out as I wanted a fresh comparison.

After taking the token Out I re-pressurized the shock and re-set sag. After a mile or so I decided on a whim just to check the pressure again and it seemed to have lost about 20 psi. I pumped it up again and stopped again in about another mile - and again it had lost pressure.

When I got home I depressurized and opened up again just to check and everything looks A-OK. So I pumped back up to 170 psi and within a couple of hours it was down to 100 psi. The weird thing is that when I keep the pump attached it doesn't lose pressure - Not at all. As soon as I release pump the pressure starts to drop.

Someone had a theory about having to charge the negative air chamber but this wouldn't cause the shock to lose air surely?

The shock is brand new on a brand new bike and obviously I'll send back under warranty but if there is a simple fix that would negate me having to send it back to supplier I'd prefer to do that.

Any ideas or thoughts?

Thanks in advance

Neil
I have had two of these POS shocks fail in less than a year. RS refusedto warranty and said I should have had serviced the shock. It failed at 150 miles, was rebuilt and failed again at 650 miles. Had a spare from my bike shop on for the last 200 miles waiting for a warranty response from RS. It failed today in the same way. Dropped from 230psi to 110psi. Aired up again and dropped from 230 to 170 on a 5 mile XC loop.

I hope you have better luck with RS than I did. Waiting on a new Fox to replace this garbage.

JBM
 
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