Rear Shock – Harsh bottom out and not achieving full travel

Gave my new (to me) Segment a gentle first ride on Saturday.

I found that landing from small jumps there was a harsh bang. I thought i was running the rear tyre too low, but it seems the rear shock was bottoming out even on little drops. More air improved things but that was after putting 250psi in and even then it bottomed out (i’m 95kg)

My experience of shocks is that after letting all the air out you could fully compress the shock. This one you can’t (see below)

Is this normal or is something not quite right? I’ve added a bigger volume spacer to see if that helps things, but wondering if something fundamental is not right with the shock

IMG_8605 by Dave Aspinall[/url], on Flickr

You need to measure the distance the shock has moved, not the amount of you are left seeing. Many different length of shocks end up with an extra bit like that when bottomed out. Also bear in mind that, unless you’ve really loaded it up in that photo, you’ve got to compress the bottom out bumper too – a good 5mm+ thick on Foxes iirc

fox ctd? Utter turd but some volume spacers will help.

Sounds like maybe a service would help? Perhaps air is where it shouldn’t be an oil is where it shouldn’t be.

Wallow through the mid stroke and bottom out too easily. Fox CTD.

It probably needs some volume spacers to get it to ramp up more – the air chamber got larger vs earlier RP23s and a lot of bikes didn’t work with it (but manufactuerers fitted the shocks as stock without volume reducers.

If it needs a service, get it Pushed – turned my CTD into a really good shock.

Just for a comparison, I’m probably not far off 95kg kitted out and run my shock at about 200psi on a segment with a Fox Float DPS EVOL Performance shock. It usually leaves about 3/4mm of shaft showing after bottom out.

Whats the 4 digit code on the shock?

The fact that the remaining shaft is clean I’d say your stopping at the bumper there and you hit full travel on the ride, your also in trail mode in the pic.

oldtalent – Member
fox ctd? Utter turd but some volume spacers will help.

Depends on the bike.
The ones I’ve had on VPP have worked really well, your just asking a lot of it on an orange.
Some tips to get going with though – pressure is a number your shock pump invents – it should be consistent for that pump though.
What do you need to set to get 25-30% Sag on the back?

Start with good sag set in Decent mode and go from there

Also if the bike is new to you when was the shock last serviced?

Fit a VORSPRUNG CORSET AIR SLEEVE

poah – Member
Fit a VORSPRUNG CORSET AIR SLEEVE

Which will force you down the road of running 33% sag iirc? Not a winner for all setups

Just for a comparison, I’m probably not far off 95kg kitted out and run my shock at about 200psi on a segment with a Fox Float DPS EVOL Performance shock. It usually leaves about 3/4mm of shaft showing after bottom out.

What?? I’m same weight as you kitted up and runing 300psi to give me 30% sag on my Five with a Float X EVOL

I’m 95kg and ran 260psi in a fox DPS on my segment.

I bought the DPS shock to replace the CTD that came with the frame as it was going to be a similar amount to tune the CTD as to buy a DPS from ebay.

The CTD never bottomed out harshly. It had the largest volume spacer in mine.

Great bikes!

Which will force you down the road of running 33% sag iirc? Not a winner for all setups

no it won’t

Damping might be blown, going by the banging noise – and assuming it feels harsh through your feet too?

Shock is secondhand with frame I assume? Get it checked out properly as you may need to contact the seller.

is it a 200 x 50 shock? same length and construction as a 200 x 57 but with less stroke. you won’t use all the available shaft. its certainly what it looks like. How much of the stroke have you used? if its 50mm then its probably fine.
Never had an issue with the CTD, mine was awesome and still is. have you tried different volume spacers?

land better?
hth

So more people quoting pressure from massively uncalibrated shock pumps….

Yeah, that always makes me chuckle too 😆

So more people quoting pressure from massively uncalibrated shock pumps….

To be fair I’ve got/had a pile of shock pumps and they all read remarkably consistently (at least within about 10psi). I’ve got one that’s failed recently but that’s stopped reading at all.

What?? I’m same weight as you kitted up and runing 300psi to give me 30% sag on my Five with a Float X EVOL

I know. Even I think it’s a bit odd to be honest but that’s what my “massively uncalibrated shock pump” is telling me. 🙄

I went for the obvious 250psi to start with as that’s what most of my other fox shocks have been run at but I had to keep dropping it to get it to feel right.

OP. Maybe ignore my post. I may be in the minority.

I know. Even I think it’s a bit odd to be honest but that’s what my “massively uncalibrated shock pump” is telling me.

Maybe all us forum members should club together to buy a communal shock pump so that we can have more meaningful thread discussions…