NRS2 + chamber pressure when - chamber blown?

[John Crankshaw]

The negative chamber on my NRS2 won't hold any pressure. Valve problem. Until I get it fixed, should
I run my + chamber at my body weight minus the 50 lbs that's missing from the neg chamber?

Kinda makes sense to me...

John

 

[Watimena]

Ummmmmm

I wouldn't ride it until I fixed it dude......

Jeremy

"John Crankshaw" <[email protected]> wrote in message
news[email protected]...
> The negative chamber on my NRS2 won't hold any pressure. Valve problem. Until I get it fixed,
> should I run my + chamber at my body weight minus
the
> 50 lbs that's missing from the neg chamber?
>
> Kinda makes sense to me...
>
> John

 

[John Crankshaw]

Good advice, but I've got just one more desert ride before going back to snowy Michigan. And I'm
thinking the valve has been blown since the bike was new. Just discovered it by accident, since the
neg pumps up fine and looks good, but loses the pressure immediately on disconnecting the pump. I
discovered it by going back on with the pump immediately one time...

So one more ride...

Got any opinion on the + chamber pressure for this one ride, Jeremy.

John

Watimena <[email protected]> wrote in message
news:[email protected]...
> Ummmmmm
>
> I wouldn't ride it until I fixed it dude......
>
> Jeremy
>
> "John Crankshaw" <[email protected]> wrote in message
> news[email protected]...
> > The negative chamber on my NRS2 won't hold any pressure. Valve problem. Until I get it fixed,
> > should I run my + chamber at my body weight minus
> the
> > 50 lbs that's missing from the neg chamber?
> >
> > Kinda makes sense to me...
> >
> > John
> >
>

 

[A J S]

Like the other guy said, You shouldn't ride it. At least ring and get a price on a new shock so that
you know how much your ride may cost you.

BUT since you think it's only the valve why don't you replace it ? The centre of those car type
valve screws out and can be replaced. Go to your (someone's) boot and get the one out of the spair.
If it's the valve this will (probably) fix it. You can even get a special little tool to take the
valve out but a little flat head screw driver or two should do it with care.

AJS

"John Crankshaw" <[email protected]> wrote in message
news[email protected]...
> The negative chamber on my NRS2 won't hold any pressure. Valve problem. Until I get it fixed,
> should I run my + chamber at my body weight minus
the
> 50 lbs that's missing from the neg chamber?
>
> Kinda makes sense to me...
>
> John

 

[Allen]

"the neg pumps up fine and looks good, but loses the pressure immediately on disconnecting the pump.
I discovered it by going back on with the pump immediately one time."

Is there anything indicating pressure loss other than the lower reading the second time you screw
the pump hose on? The negative chamber has very small volume. It loses quite a bit of that volume,
and therefore pressure, when you screw the hose on - the air has to fill the additional volume of
the hose before it hits the gauge. Maybe that's all that's happening.

 

[John Crankshaw]

Nope. I've pushed the valve after pumping up the neg chamber. It's not holding any pressure unless
the pump is screwed on.

J

Allen <[email protected]> wrote in message news:[email protected]...
> "the neg pumps up fine and looks good, but loses the pressure immediately on disconnecting the
> pump. I discovered it by going back on with the pump immediately one time."
>
> Is there anything indicating pressure loss other than the lower reading the second time you screw
> the pump hose on? The negative chamber has very small volume. It loses quite a bit of that volume,
> and therefore pressure, when you screw the hose on - the air has to fill the additional volume of
> the hose before it hits the gauge. Maybe that's all that's happening.

 

[Joe Yannie]

Try installing a new valve core ( or snugging it down), your seal in the core may be bad. To check
this, pump it up( to about 100psi) and leave the pump attached for a little while. If you see
significant leakage after 5 minutes then you know it is the seal inside the chamber and not the
valve core.

Otherwise I don't think having no pressure in the negative chamber really effects the NRS suspension
design that much ( too much makes it really active). it was designed to run with no sag. The 50 psi
they recommend is almost a token pressure.

I had the opposite problem, the positive chamber was leaking into the negative chamber and the
suspension was getting progressively more active, RS did not put any lube inside the chamber so it
ruined the rubber O-ring. Which makes me think it may be your valve core.

Joe "John Crankshaw" <[email protected]> wrote in message
news[email protected]...
> Nope. I've pushed the valve after pumping up the neg chamber. It's not holding any pressure unless
> the pump is screwed on.
>
> J
>
>
>
> Allen <[email protected]> wrote in message news:[email protected]...
> > "the neg pumps up fine and looks good, but loses the pressure immediately on disconnecting the
> > pump. I discovered it by going back on with the pump immediately one time."
> >
> > Is there anything indicating pressure loss other than the lower reading the second time you
> > screw the pump hose on? The negative chamber has very small volume. It loses quite a bit of that
> > volume, and therefore pressure, when you screw the hose on - the air has to fill the additional
> > volume of the hose before it hits the gauge. Maybe that's all that's happening.