Boost value will not keep pressure meaning shock blows through mid travel very quickly. Although shock is 11 months old has genuinely not been used much (e.g. 10 rides due to arrival of first child). Will this be covered under warranty or will Mojo claim its due for annual service anyway at c.£110?

Erm, only mojo can answer that. Not wanting to be a **** but are you absolutely certain it's losing air? The reason I ask, is that Dhx air shocks are renowned for blowing through their mid travel. I've had about 4 now and depending on which suspension design i.e. 4 bar, single pivot etc. This is more evident. It felt ok on my patriots, but not great on my nicolai. Obviously this may be down to leverage ratios and all other kinds of variables, but there quite a few fixes/hodges out there to address it.

One thing worth noting is that some bike/frame manufacturers seemed to plonked a Dhx on bikes they wanted to say were more "core", when in actual fact a basic float is more than good enough. In other words, sometimes, no amount of farting around will cure it.

Unless it was bought from Mojo, it's really for you and the shop to work out. Though, as it's not a visible fault, I'm sure the shop would return it to Mojo for a view.

Depending on how handy you are, it could be a home service job if they wont warranty it.

Or 'Trading Standards' if they won't warranty it and you're convinced they should.

How much pressure is it loosing?

Losing quite a bit pumped up to 175 psi at start of ride and was at 130 at end 4 hours later

Go to Halfords, buy a valve core remover fo about £4, remove the valve core from the piggy back thingy, pop a new one in (out of an old inner tube)

See if the shock still looses air by dipping it in a sink full of water.

My DHX coil I bought s/h leaked from the piggy back and exactly as above worked for me. Replacement valve core is still in there and still fine, 2 years later.

Losing quite a bit pumped up to 175 psi at start of ride and was at 130 at end 4 hours later

the IFP chamber is tiny, are you sure that's not just the pressure 'loss' from the pump equalising?

That little pressure loss is the pump filling with air when you attach it. Nothing is wrong.

Guys – can we please stop confusing your rights under various legislation such as the sale of goods act and a warranty – they are not the same

Sale of goods act gives you rights. This is a part of the contract between you and the person you bought it from.

A warranty is extra over and above these rights is discretionary and is usually with the manufacturer or importer

In this case at 11 months old it is up to the buyer to show that the unit has a manufacturing fault and that it would be expected to last longer than this. Getting a full replacement / repair / refund under the sale of goods act will be difficult.

The importers warranty might be of help – it depends on the terms of it.

I'm with solamanda – it can be a right sod to remove the pump without losing a lot of air from such a small chamber. Try putting 20-30 lbs extra in and then try it.

it can be a right sod to remove the pump without losing a lot of air from such a small chamber. Try putting 20-30 lbs extra in and then try it.

DO NOT DO THIS. Its simple. Attach a pump to a small volume air chamber and the pressure drops as it fills the pump. If you pump up the air chamber and remove the pump you will hear air escape from the PUMP only. The valve in the shock retains the air.

This is a common idiocy. Jumpy pump it up and ride 🙂

a common idiocy

Nice. Perhaps mistake??

Anyway, I think that's something I've read and read in magazine articles over the years, and yet in my experience doesn't particularly ring true.

I personally believe that when I'm unscrewing the pump, my fingers are not quick enough to unscrew past the point at which the pump is still slightly deppresing the valve core, thus allowing a little air to escape. In such a small chamber, even a little air can have a big effect on psi.

solamanda is right .

Mildred,

Do you think the designers didnt think of that? The pump is designed to close the valve in the shock before the seal is un done, thats why a shcok pump look s nothing like a track or foot pump which use a different arrangement to flow more air quickly, but leak when released.

If you unscrew it really slowly, in your hypothesis there should be a point where the air could escape continuously. There isn't.

Could well be my pumps then, because I lose up to 15 psi from my forks and 30-40 psi from my shock.

When you remove the shock pump you are not losing the pressure from the shock. You are losing the pressure from the pump/gauge/hose to the valve. This has to be at the same pressure as the shock when you have just pumped it up to the the desired pressure.

When you put the pump on and open the valve some air comes out of the shock to fill the hose/gauge/pump. As the volumes are so low in the shock this means that the pressure drops a bit. So you can pump a shock up to XX PSI and then if you remove and then re attach the pump the pressure will likely be down a bit.

There needs to be pressurised air in the gauge for it to work.. This will be what you are losing.

Pump it up to the right PSI and then leave it and don't sweat it I reckon.