Officially this is the Fox Racing Shox 34 Float 29 and the Float RP23 rear shock. I’ve run this suspension on a Transition Bandit 29er (previewed for MTBR here) and now had over 50 rides on the bike. I’ve run Kashima coated forks for over 100 rides on my personal bikes and therefore feel comfortable speaking to the coating’s longevity.
As an aside, it never ceases to amaze me when a review in mid-year is already dated. The Fox website is loudly proclaiming its 2013 lineup on the homepage but for the sake of posterity, here in June 2012 is the Fox 2012 Fork lineup. I’ll make no excuses for taking my time to vet a product and give impressions based on more than cursory use. First I’ll briefly describe technical details. Then I’ll relate impressions.
Self-filmed random places in Mount Seymour trails in North Vancouver where I found terrifically flat “old-school” drops. A fantastic place to test the ability of front and rear suspension. And yes…I had a lot of fun making this video
Lee Lau’s biases
I am 160 lbs and 5’11″ and have had over 15 years experience riding bikes in North Vancouver, Squamish, Whistler, the Chilcotins and many other areas in B.C. and Alberta. I’ve also made many bike trips to Switzerland, Utah, Washington, Oregon, California and the Yukon (for example) so I’ve had some experience biking in a variety of terrain. My bias is towards pedalling up and unlike many people who learned to ride bikes on North Shore trails, I actually enjoy riding (and sometimes bushwhacking) uphill.
My personal bikes are a Santa Cruz Tallboy, Pivot Mach 5, and a Specialized Demo 7. As previously mentioned, I had this front and rear suspension on a Transition Bandit 29er. I also have Kashima-coated Fox front and rear suspension on the Pivot and the Tallboy so have had over 100 days on Kashima coated suspension.
Fox 34 Float 29er Technical Details
This fork is part of the family of Fox’s ubiquitous FIT-cartridge equipped front suspension found throughout its lineup. New for this year are 34mm stanchions and 29er specific arches (more room for the bigger wheels). I tested the Float version which was a fixed 140mm travel (travel can be adjusted down with internal spacers but it’s not adjustable on the fly). From the website here are other details
- OEM colour is black. Aftermarket colour is white
- The quick release is Fox/Shimano’s 15mm through-axle
- Claimed weight is 4.32lb/1.96kg with (1.5″ tapered steerer). I neglected to check weights on my tapered version till I cut the steerer to 7″. Even then it weighed in at 4.01lbs. I had no idea that 1.5 steerers were that heavy
- Travel is 140mm/5.5″
- Post-style mounts for disc brakes
- Suspension is an air spring (found in the left leg). Adjustments are low-speed compression and a lockout flip switch on the top of the right leg. Rebound adjustments are on the lower right leg
- Axle to crown measurement is 552.8mm (520mm for the Fox F29 120mm if you’re curious – more measurements for different forks are here)
- There’s no official tire size limit I could find stated. This may be academic as 29er tires haven’t got to ridiculous sizes yet. I fit a 2.5 WTB 29er tire in this fork without issue.
The F34 Float’s FIT technology is old news so I’ll waste only a few words on it. Basically FIT (or Fox Isolation Technology) incorporates a bladder system to keep oil and air separate presumably giving a more consistent shock feel over the course of a long downhill. It replaced Fox’s old open bath designs which were a bit heavier (more oil was necessary). Finally service intervals should be longer as the damping oil in the cartridge no longer also serves as lubricating oil – thus theoretically reducing wear and tear.
Kashima coating applied to the F34′s stanchion is also old news. It’s an anodizing process applied on the upper tubes of the fork (and the body of the RP23 rear shock). The claimed effect is to reduce friction and increase reliability by increasing surface hardness of the aluminium. Borrowed from motorcycle technology, Kashima coat is impregnated molybdenum sulphide deposited on micropores on the surface of hard-anodized aluminum. Since 2009 when it was first introduced into the international mountain bike racing circuit, the distinctive gold colored Kashima coated stanchions have been reported to offer better lubrication characteristics, attain a level of hardness and abrasion resistance four times tougher than standard hard-anodized aluminum in lighter weight package. Tech weenie details aside Kashima is gold – coloured and everyone knows that gold coloured parts are 3.141529x stiffer, stronger, faster …
SKF Seals are new for Fox forks in 2012.Popular in motocross industries they are purportedly lower friction and seal better (which kind of begs the question why it took Fox so long to start using them – but maybe I’m just cynical). If you have a 2012 fork you’ll have those seals. It’s worth noting that you can purchase them aftermarket from Fox direct and install them.
Fox Float RP23 Technical Details
The RP23 really needs no introduction. It’s become the standard for rear shocks and, with Kashima coat in 2012, is now the gold standard. Otherwise it’s unchanged from previous variants. Technical details follow
- Claimed weight of 0.46lbs for the 6.5×1.5 size (no reducers)
- Lots of different sizes from 5.50 x 1.00 all the way to 8.5 x 2.5
- Adjustments feature rebound, propedal on/off, compression adjustment and air spring via a schrader valve
Three key technologies bear highlighting. Kashima is already explained above. The others are Boost Valve which is an actual valve in the rear shock (pictures, video and more tech speak here). The RP23 (and RP2) have always been velocity sensitive in that the air spring activates differently depending on whether an impact is high or low speed. Boost valve is position sensitive; activating to increase compression damping at the bottom part of stroke ie when the shock is deeper in its travel. The theory is that the rear shock preserves plushness and small bump sensitivity in smaller hits but ramps up during bigger hits that use up all of the stroke.
Adaptive Logic is a fancy name for re-arranging the Propedal lever so it can thoroughly confuse riders who were used to the old lever. Basically now you set a preferred level of open compression (0 to 2 with 0 being wide open) and then flick a switch to go from “climbing mode” (or compression level 3) to the open compression with one flick of the switch. Mild complaints aside once you learn the new habit it’s pretty easy to remember which way to turn the lever of the RP23.