Review: 2012 Fox RP23 with Adaptive Boostvalve

A few weeks back I reviewed the 2012 Fox TALAS RLC FIT. While I was reviewing that fork I also had the new RP23 installed to control the rear of the bike. Add those two together and you have a lot of butter. It’s a silky-smooth ride for sure, even on the roughest of terrain. …

A few weeks back I reviewed the 2012 Fox TALAS RLC FIT. While I was reviewing that fork I also had the new RP23 installed to control the rear of the bike. Add those two together and you have a lot of butter. It’s a silky-smooth ride for sure, even on the roughest of terrain.

Specs

Foxs 2012 RP23 with Adaptive logic boost valve is a significant upgrade over the previous model. The most obvious change is the color; well, it’s not so much a color change as a coating change. Not only did Fox coat the air piston in Kashima, but they coated the air sleeve with it as well. This years RP23 is all Kashima – a nice upgrade for sure. Another significant change lies in the way you set the dampening, with revamped compression/rebound and platform settings, making it much more user-friendly.

Now before you get all excited and rev up your car, ready to race out and get one, there are a few things to consider. First up: tuning the shock for your ride. Before I received my shock I had to let Fox know the bike model, as Fox tunes the dampening shim stack to the leverage ratio of your bike. Grouping builds in a few tune levels, this ensures the shock has the best control over your rear wheel. As a result, a product such as this is best purchased new, or at least from a someone who used it on a bike with the same leverage ratio as yours.

The Adaptive logic boost valve is pretty easy to use and gives you the freedom of absolute control. The design of the valve allows you to choose one of two platform options. The climb/sprint mode has the full level of compression for those uphill rides or sprints. Then, with a flick of the switch, the shock opens up to one of three levels: full open, medium, or light. The full open works great for faster descents and rougher terrain on a slope. The other two settings, the light and medium, are great to fine tune to the terrain that you’re riding when not climbing.

At this point you’re probably wondering how much of a weight penalty you’re looking at to use the RP23. The good news is that they are pretty light, but they aren’t the lightest out there as this shock is still all aluminum. A 6.5 x 1.5 comes in at just over 200 grams. My 7.5 x 2″ unit comes in at 213 grams (without spacers), making it one of the lighter units I have tested in that length. I am still amazed at how light people can make these things.

Installation

Installing the RP23 is pretty easy. On most frame sets you only need to remove the two bolts holding the shock in place. I always recommend replacing the hardware that attaches them with new stuff (sold separately), simply because the old hardware has already been worn in and, in most cases, worn out. After all, wearing out the new bushings that come with the shock is no fun.

To set up the rear shock, you will need a high pressure shock pump and a friend. In order to get things set the right way you need to prep yourself. Get your gear on so you are at your riding weight. For example, I weigh in at 205lbs with hydration pack (filled with water) and all of the munchies that I would take on a normal ride.

So hop on the bike and pedal around, bouncing a bit to get things all settled, then stop by your friend without dismounting and have him/her set the o-ring back against the air sleeve while remaining in your riding position. Then carefully dismount and measure the distance from the o-ring to the air sleeve. In my case I wanted to see 1/2″ of sag (25% sag). It took a few tries to get the air pressure right at about 165psi, but it’s necessary to take the time.

Once that was set I concentrated on my rebound setting. I went out and hit a familiar section of trail with a good mix of features. I was trying to identify a packing-down feeling (too much rebound) or a bucking feeling (too little). Either of those feelings needed to be tuned out. In the end I played around between 3-5 clicks clockwise.

The next setting was the adaptive logic part. That was pretty easy to set (three choices), and was accomplished on the same trail section. You’re looking for good control over the wheel with little or no wallowing feeling out back. On the jumps, look for too much travel. If that is the case, bump it up a level. I ended on the highest setting of 2 on that dial, and after that I used the ProPedal lever often on the climbs.

The Test

So how did the new Rp23 feel on the trails? Keeping up with the rest of the Fox line up, the RP23 performed superbly, as I mentioned in my opening statement. The Rp23 is very smooth, with no stiction that I could detect.

My usual riding spots are Kelso and the Don. Both spots offer up a wide range of terrain, with Kelso having more aggressive slopes and rocky patches that make a great test track for shocks, really showing how they interact with the terrain. The Don has a mix of technical terrain with webs of roots all over that also challenge the shock in the rutted stuff.

The RP23, in my opinion, feels a bit softer than many other similar shocks, and I found that I spent a lot of time with the ProPedal on. I did play with the air pressure by adding a bit more, but I found that it just made it harsh–not exactly what I was looking for. The shock is a bit more active compared to other units which tend to ramp up quicker.

After my test I decided I need to rethink how suspension should work. The plusher feel did offer up more traction and having a more active wheel helped the bike follow the terrain a bit better, providing more contact over the surface. I guess that is what they mean by a “bottomless feel.” Overall I have to say that the RP23 is at home on any bike up to 5.5″ of travel. After that you may want to consider something a bit more aggressive.

All in all it’s a great shock and a nice upgrade for when you want more control over your ride. Fox has the Rp23 pegged at $420 MSRP which is a premium price for a rear shock, but still not too far from the cost of the other brands at this level.

I would like to thank the folks at Fox for sending down the RP23 for a review.