First ride out on a new (to me) Fox DPX2 today.
I bought the shock second hand. All I know of the history is that it was taken off the same type of frame I have just fitted it to - Transition Sentinel 2019 model year.
57mm stroke shock. I'm 14.5 stone and running 250psi. (About 35%sag seated - may be optimal to have a little more pressure)
I started the ride with the rebound 5 clicks from closed as per fox recommendations for that 250psi pressure. Shock performed ok downhill, maybe a little faster rebound than I prefer, but still felt good.
Uphill was a different story though. With the LSC fully closed, when riding up steep climbs in the lowest gear it got very very bobby - kind of like it was resonating.
I had no more LSC to apply so tried winding the rebound in which helped a hell of a lot by stopping the resonance, but still bobbing more than I would like. Certainly compared to my last rockshox shoc, it bobbed way more)
At this rebound fully closed setting it felt preferable downhill also.
I am not a light rider so I am running moderately high pressures, but I'm nowhere near the limit of what you are supposed to able to run on this shock. Yet I don't feel I am getting enough LSC damping when pedaling, and the shock also seems best when I am having to run max rebound damping.
I know both the LSC and the rebound adjustments are both making a difference, as I can feel them having an effect. Just not enough effect.
Sound like a damping issue? It seems almost like the shock may have been tuned for a much lighter rider tham me in the past, running much lower pressures.
Does anyone know whether a tuning outfit such as TFtuned would be able to sort this kind of issue out?
Ta!
Are the adjusters actually working? Easiest way to check is if the open/trail/climb one makes a difference. Always a good idea to factor the price of a service into buying second hand. At 2-3 years old it could be begging for one (and then adding on a custom tune is dirt cheap anyway)
Yeah they're definitely working. No weird noise es or anything. I got it for a good price so I'm not too fussed if I have to send it for a service and tune....just so long as that will sort the problems out.
Downhill it feels great, even if the rebound is all the way closed. Uphill still way too much Bob even with full LSC on.
I'm a chunky monkey too and run the same shock on my kona 153
I run 280psi and the lsc almost at max
put more air in the shock
Chexk the base tune on the fox website.
DPX2 is well known to need a lot of pressure to work, 250psi is probably a bit low, move it up to 300 and see how that feels, 35% sag on a sentinel is a bit too much, 30% would be about right for up and down, if you want it to feel better on the ups, 25%.
When i had the patrol i preferred it with the coil rear, i got a DVO Jade X with progressive spring, worked well, could dial it in a little more if required, and it had a better lockout style function over the DPX2, i just never got on with that shock, same on my current bike, DPX2 was taken straight off and replaced.
I'm a more of a biffer than you and had similar issues, had to run it on the last click. Service and custom tune at TF Tuned sorted it.
Put more pressure in to start... On a bike like a Sentinel, 30% sag would be too much, around 25-28% more like it.
But if that doesn't sort it, then something definitely sounds wrong. If there's one criticism to be levelled at the DPX2 when stock, it is not a lack of damping, more that they tend to be quite overdamped from new!
Something worth checking, don't take your sag as a 35% visual of the shock body, you have a 57.5mm stroke on a 65mm body, so do 30% of 57.5, a range in mm is written on the back of the seat tube. Also it's quite a linear link, you might want the biggest volume spacer (although officially the compression ratio is too high) or see if anyone is selling a Cascade link for it and convert to essentially a Sentinel V2 🙂
Thanks all. The tune marked on the body is DM83 and this is the correct tuneid for the bike (I checked before I bought it)
Here's the info the fox website chucked out
2019 Performance Elite Series FLOAT
Part number: 973-60-976
Short ID: DM83
Description: 2019, FLOAT DPX2, P-Se, A, 3pos-Adj, Trunnion, Evol LV, Transition, Sentinel, 205, 57.5, 0.9 Spacer, CAL001, RAL001, Rezi A F M, Standard Logo
I presume CAL001 and RAL001 refer to the compression and rebound, but I can't find any reference information on those codes.
@konanige interesting you had similar issues
I used to be the same weight and always had to get my Fox shocks retuned at first service. Was always maxed out on rebound. These things are designed around the “average” 70kg rider and the further away you are the more difficult they are to get right in standard form.
Mild retune has always made a big difference. Last time I just asked for tweak to shim stack equivalent to another 2-3 clicks, added 20-30 quid to price of service.