Rear shock leaking air?

flamin'trek

Likes Bikes and Dirt
The rear RS shock in my Trek Remedy seemed to be bottoming out a bit easy so I check the air pressure and when I connected the pump it showed 0. Few pumps and it was up around 150 so I tested it again and it showed 0 on connection. Didn’t seem to be leaking, but after pumping didn’t seem to be any better. Bottomed our again yesterday during some light riding. Bike has not done much heavy riding yet.

Think it will need to go in for a check, but is it normal for a shock pump to need a pump or 3 before showing pressure for some shocks? My previous experience says as soon as you connect it shows the current pressure.
 

Flow-Rider

Burner
Try turning the pump fitting really tight so that it pushes on the schrader valve and reads air on your gauge, I get this all the time with my Lezyne shock pump. Sometimes you need to unscrew the valve in the shock a touch. If the shock has an evol air-can you need to pump them up in stages while cycling the shock.
 
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link1896

Mr Greenfield
Some shock pumps don't engage the schrader valve into the open position, relying on the air pressure built up in the pump to open the valve instead. Sounds like yours is one of these.

Can we see a photo of the end of the pumps fitting looking up into it?
 

flamin'trek

Likes Bikes and Dirt
Will try to get a photo of the end of the pump, but in the mean time I’ve checked a couple of air forks and other rear shocks and found every time I connect the pump the pressure shows as soon as it is done up, even the fork with some issues.

Checked the Remedy shock again and nothing, until I added about 3 pumps. Might have to take the shock into the shop, bike was new back in December and hasn’t been ridden as much as it should be.
 

fatboyonabike

Captain oblivious
does the pump have a two stage connection, where you screw down on the valve stem, then you screw the second knurled ring down to engage the schrader valve..it could be that you are pressurising the space between the pump and the closed valve.
how many strokes does it take to achieve 150psi?
 

flamin'trek

Likes Bikes and Dirt
does the pump have a two stage connection, where you screw down on the valve stem, then you screw the second knurled ring down to engage the schrader valve..it could be that you are pressurising the space between the pump and the closed valve.
how many strokes does it take to achieve 150psi?
Doesn't have a two stage connection, simply screws straight on and works with other shocks and forks. Takes about 3 pumps to get to pressure on the Remedy shock.
New valve mate.
Thanks. Does that mean just the insert for the valve? I'll be taking it to the shop anyway as it will still be under warranty.
 

c3024446

Likes Bikes and Dirt
Wait...from 0psi to 150 in 3 pumps of the shock pump?

I dont think youve connected it properly, prob need 100 pumps.


Sent from my iPhone using Tapatalk
 

flamin'trek

Likes Bikes and Dirt
Wait...from 0psi to 150 in 3 pumps of the shock pump?

I dont think youve connected it properly, prob need 100 pumps.
Seems there is something wrong with the shock as the pump appears to work fine on other stuff. I'm not connecting it any different to them.
 

c3024446

Likes Bikes and Dirt
If you are going from 0-150 in 3 pumps you are only filling the shock pump hose with air......

Sounds like your shock has some air in it, but not enough, but the pump won;t connect properly. If you depress the valve in with something else, i reckon you'll hear a big rush of air....but you'll need to be able to pump it back up again.

Your shock isn't leaking - the pump just isn't connecting properly.
 

fatboyonabike

Captain oblivious
Wait...from 0psi to 150 in 3 pumps of the shock pump?

I dont think youve connected it properly, prob need 100 pumps.


Sent from my iPhone using Tapatalk
Yep, that's what I was getting at
get a better shock pump
here's a demo, sorry about the lycra..totes uncalled for!
 
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Tubbsy

Packin' a small bird
Staff member
Yep, let's keep this kind of thing off the site please.

Both lycra and derogatory comments/
 

flamin'trek

Likes Bikes and Dirt
Concur. What on earth would you wear that kind of kit while maintaining mtb.

Well, tried again this evening. Before attempting I gave the valve a bit of a jab and let some air out of the shock. Then when reconnecting the pump worked properly, but maybe I tightened it a bit more this time.

Next step, reassess the shock in the saddle, but raining and now dark.
 

Flow-Rider

Burner
The problem is usually this height here in diagram below, some shock pump couplings have a long nib that depresses the internal valve easily and some don't. You could try changing the internal valve but most are the same length .

valve.jpg
 

mark22

Likes Dirt
Doesn't have a two stage connection, simply screws straight on and works with other shocks and forks. Takes about 3 pumps to get to pressure on the Remedy shock.

Thanks. Does that mean just the insert for the valve? I'll be taking it to the shop anyway as it will still be under warranty.
Yep just the insert
 
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