Thought this might be of interest to some...
Been riding an XCT-5 for a couple of years with the Foes/Curnutt XTD Air shock and have been happy with the performance for my XC riding style on a wide variety of terrain. Had the opportunity to pick up a new RP23 with the updated boost valve (uses the same licensed SPV patent as the Foes/Curnutt shock) for next to nothing, so I went ahead and gave it a try along with the Foes adapter. I'm not up to speed on all of Fox's tunes and such, but the stickers on the shock say "boost valve tune 175, velocity tune M, rebound tune M". After playing around with the adjustments some, I settled in on 200 lbs in the air chamber (I'm not svelte), rebound about 3 clicks out, and boost valve on 3. Been on a couple of rides now, one in Phx Mtn Preserves (220, fenceline, 8/8A, 304, 1A, 100), and one up in Flag (Shultz, Climb 3, Sunset, Shultz).
I hate to say it, but I like the bike better with the RP23, and not by a small amount. The bike is noticeably smoother in every situation. Downhills are really plush with the pro-pedal set to open. With pro-pedal engaged, the ride is still much smoother than the XTD ever was. It's nice to be able to switch the platform on and off. The only downside is that the rock-solid pedaling performance of the XTD is definitely compromised, even with the pro-pedal on the highest setting (3). Most of the time that's not a big deal for me since I'm usually not in a hurry, but I could see it being an issue for someone who's looking for the best efficiency while climbing. The one thing I don't know about yet is bottoming control. The XTD could be run at low spring pressures and still provide perfect bottoming control (in fact I never felt the bike bottom in 2+ years even though it was using all its travel). I haven't really bombed into anything big yet with the RP23, so I can't comment on how it will control in that situation.
Next step for me will be to check and see if any other tunes are available for the RP23 that might firm up the platform just a little bit. I will also likely send the XTD back to Foes to get it rebuilt (secondary chamber has been leaking) and see if they can detune it some to soften up the response a little to make it more like the RP23. Something inbetween the two would be ideal for me, but for now the RP23 will be staying on the bike.
Cheers,
-Brian
Been riding an XCT-5 for a couple of years with the Foes/Curnutt XTD Air shock and have been happy with the performance for my XC riding style on a wide variety of terrain. Had the opportunity to pick up a new RP23 with the updated boost valve (uses the same licensed SPV patent as the Foes/Curnutt shock) for next to nothing, so I went ahead and gave it a try along with the Foes adapter. I'm not up to speed on all of Fox's tunes and such, but the stickers on the shock say "boost valve tune 175, velocity tune M, rebound tune M". After playing around with the adjustments some, I settled in on 200 lbs in the air chamber (I'm not svelte), rebound about 3 clicks out, and boost valve on 3. Been on a couple of rides now, one in Phx Mtn Preserves (220, fenceline, 8/8A, 304, 1A, 100), and one up in Flag (Shultz, Climb 3, Sunset, Shultz).
I hate to say it, but I like the bike better with the RP23, and not by a small amount. The bike is noticeably smoother in every situation. Downhills are really plush with the pro-pedal set to open. With pro-pedal engaged, the ride is still much smoother than the XTD ever was. It's nice to be able to switch the platform on and off. The only downside is that the rock-solid pedaling performance of the XTD is definitely compromised, even with the pro-pedal on the highest setting (3). Most of the time that's not a big deal for me since I'm usually not in a hurry, but I could see it being an issue for someone who's looking for the best efficiency while climbing. The one thing I don't know about yet is bottoming control. The XTD could be run at low spring pressures and still provide perfect bottoming control (in fact I never felt the bike bottom in 2+ years even though it was using all its travel). I haven't really bombed into anything big yet with the RP23, so I can't comment on how it will control in that situation.
Next step for me will be to check and see if any other tunes are available for the RP23 that might firm up the platform just a little bit. I will also likely send the XTD back to Foes to get it rebuilt (secondary chamber has been leaking) and see if they can detune it some to soften up the response a little to make it more like the RP23. Something inbetween the two would be ideal for me, but for now the RP23 will be staying on the bike.
Cheers,
-Brian