As I recently turned 50 I treated myself to a new Trek Fuel 8, I have tried a few times to set up the rear shock (CTD I think) but each time I have gone out I have pushed the o ring of the bottom of the shock.

I have added more air each time I have gone out, it may just be a combination of getting a bit quicker each ride or the shock breaking in.

Can someone tell me what should the sag be set to?

thanks

http://locotuning.co.uk/rear-shocks.html

Air volume spacer may help too.

It’s not necessarily a problem that you are using all of the travel. I’d expect to use all of the travel on mine on most rides.
It’s surprisingly easy to use most of the travel on fairly small compressions if you are seated at the time, it doesn’t mean that the shock won’t cope with bigger stuff or that it’s set up wrong though, it’s amazing what the damping will do to keep it under control.
Is it bottoming out harshly or doing anything else that feels wrong when you are riding?
Edit: How much sag are you running and how are you setting it?

IIRC the DRCV shocks on those require a unique/slightly different setup process – google it if so.

Sag can be set to anything you want its personal preference but the recommended range is about 20% – 30%

At 30% the shock will be more compliant and produce more rear end grip but you could end up bottoming out more or rear end might bob more climbing.

at 20% the shock will bob less when climbing and sit up in its travel a bit more but then might not give as much grip as before.

Have you got one of those DRCV shocks too? I demoed a Fuel EX and Remedy with DRCV last year I found I was using up all the travel quite a lot too but it never felt harsh on either bike so I just ignored it and carried on riding.

I was also told by the shop I demoed the bike from you need to cycle the shock (bounce up and down on the bike) a few times after pumping it up and then measure the sag. The different chambers need to equalise their air pressure.

Ignore the air vol spacer ref. above don’t fit in the DRCV units.

Refer to the sag setup guidelines for the DRCV units, 25% is a good starting point adding or removeing 5 psi at a time until your happy with the smallbump sensitivity v support on bigger ‘hits’

The DRCV extra air vol chamber is equalized mid to end of the stroke so needs to be charged by cycling the unit a few times.

like your style op 8)

Thanks for all the answers, I’ll have a quiet read and try and figure it.

cheers