Rear suspension question

Hey, I keep bottoming out the rear suspension of medium - large drops. The PSI is set at the recomended amount (my riding weight about 170lbs I weight roughly 160). Should I just add more air? Or would I be better off getting some sort of spacer or damper (can’t remember what their called) put in to make the last bit of travel stiffer. (I even bottom out going around macintosh off any of the larger drops)

Rear suspension is Fox float performance Evol 140mm travel, bike is a giant trance x2 29er

Thanks in advance for any advice.

If your sag is set correctly, adding more air will help, but at the expense of proper compression damping. If you’re happy with the initial part of the stroke, you want to add some tokens to increase the progressive nature of the shock and improve bottom-out resistance.

Id try some more psi first but thats just me. Im 185lbs and run about 230-240psi in mine. I do ride pretty aggressively though so that would be a bit much for a lot of people.

Edit: i am by no means an expert when it comes to suspension.

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Had the same issue… pressure and sag were set correctly according to Fox specs but I was bottoming out on stuff at McRun. Added a larger volume spacer and problem solved.

Best part is it was a simple home job with no special tools required.


Bottoming out is not the end of the world.

Assuming your confident your shock is working correctly, I would use a high quality shock pump and start with 1-2psi increment changes.

Also, whats your rebound set at?
Are you bottoming in the same places on the trail?


I had same issue upon the first initial setup on my trek back in the fall. At the time i was 218 lbs they set the fork at 90 and the shock at 150… the bike was super spongy . The fork was bottoming out at just in rock roll transitions to flat and tbe shock on a 2 ft drop. Increased the fork to 140 and the shock to 230 . Huge difference… plus it rolls faster

I have dropped down to 200 and recduced my pressure accordingly as it begin feeling too stiff… i will be adding token spacers though soon as my skills progress

Thanks! i think im going to try adding 4-5 PSI, testing it, but i have a feeling i will likely need to add a volume spacer as u suggested, thanks!!

Thanks Josh, im gonna add some more psi, test er out, and add a volume spacer if its still happening

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Like @brightwhite said, make sure your sag is set correctly and like @Enduro_Performance said, make sure your rebound is correct. From there if you still find that you are blowing through the travel then you will want to consider a volume spacer to increase the ramp up as mentioned.

The recommended pressure is just a recommendation, you will want around 30-35% sag when sitting on the saddle in your riding position. Running 30% sag or even getting closer to 25% will make a difference but also start costing you in small bump and comfort, but it all depends on what you are looking for. If you are happy with your sag and initial travel then I would suggest tracking down a volume spacer. Fox uses single spacers that take up different volumes and you swap them out unlike Rockshox who uses spacers/ bands that can be stacked.

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Like @Enduro_Performance said, bottoming out isn’t necessarily a problem. Depending on where I am riding, I generally reach full travel on my shock and fork a few times each ride. I usually don’t even notice and can only tell because of the O-ring indicators. Unless it’s happening a lot or you are hitting the end of travel hard, it might be fine as is. After all, if you aren’t using all of your suspension travel, why have it?


You could try adjusting your rebound. If the rebound is too slow, the shock can pack down over rough terrain and then not give you full travel. On the other side, if the rebound is too fast, it can pogo off bumps, jumps and drops. Make sure you’re in the happy middle for the trails you ride.