2008 FLHX used to bottom out when riding two up at the slightest bump in the road.I solved the problem i use zero air pressure in them now and that has eliminated the bottoming out completely because they are sitting on my shelf in the progressive 440 box.Those HD air shocks fit prefect in that progressive box too ,its like the HD air shocks were built for that box by engineers.

 

Your shocks have issues if you need 40 psi to keep from bottoming out. I weigh 180 lbs, my wife 135, and I run at 12 psi and have yet to bottom out even when crossing railroad tracks.

Disregard Street Glide data. They come with shorter shocks that use more air pressure.

 

I have a SG and run 30 -35# with just me at 180# and 40-45# with the wife. I also have 1" lowering blocks...Never bottoms and handles good. I just bought a HD pump, that is the cats azz. Prob best thing HD sells. Virtually no air loss when you remove the screw on fitting. Pump cost same at their T shirts, WTH?

 

Interesting Thread. I run my at about 12 solo and may jump up to 20 with my bride on board.

 

Solo around 12 to 15. With wifey I have to put 32 to keep from bottoming out.

 

No bottoming out here either, solo riding and my weight is 185, psi set to
18 & rides nice.

When I brought the bike home I could her it and feel it bottom out a couple of times and couldn't believe a new bike would or could do that, I checked the shock pressure and it was at zero. Don't trust the that the dealer would set it up for ya either

 

Just to let everyone know that there is a pump on ebay for like 29.99 delivered I bought one and it works just like the more expensive ones. I can't seem to get the link to post.

This pump also will air up my truck air bags (Firestone's) and bicycle tires.
I have noticed that at 165 and wife around 120 I run 25psi and seems to work well solo or 2 up.

 

Let me start off by saying I have an 08 Street Glide and I weigh 218lbs (naked of course. I don't ride naked, but that's how I weigh myself). Well last summer I was running 8 lbs and I never notice bottoming out. This spring I kept feeling like I was bottoming out, so I checked the air and started running 12 lbs. It is much better. I may have to add some more.

That front fork needs help too. ?????????????

 

Street Glides bottom out easier because they are lowered.
Compressors set at lowest rate will still blow your shocks.
Bicycle pumps will not allow you the control that the HD pump has.
I'm still trying to find the perfect pressure. I'm either bottoming out or feeling bone jarring impacts over bumps. I need to spend a day riding with five pound variances until I get it right.
The Ultra seems to handle real well but it can be harsh over the rough stuff.

 

On my bike with the mrs on it I just run about 25 psi, but just my self I leave it at 19 to 20. I am going to try and up the pressure the next time I ride two up. Thanks for the post......