Getting a suspension unit, be it fork or shock, dialled for your bike and riding style isn’t something that you should take for granted. Although many bike manufacturers go to great lengths to make sure they specify the right rear suspension unit for a dual suspension bike, an amount of custom tuning may still be beneficial.
In May, I switched from racing a Scott Scale 29er Premium hard tail frame, to a Scott Spark 29er Expert frame. The build kit remained the same, with a Shimano XTR group set, NoTubes ZTR Crest rims to Shimano and Dt Swiss Hubs, and a Fox 32 Float 29 Terralogic. The mid range carbon Spark 29er came fitted with a DT Swiss M210 rear shock. This unit comes with a lockout lever, which I had always found very useful on previous Scott Sparks that I owned. However, previous models had used the DT Nude shock, which could be open, in ‘Traction Control’ or locked out. I really liked how the previous Sparks I owned rode. They were quite active, had plenty of travel available when needed, but could be locked out or made firmer right from the bars.
The DT Swiss M210 rear shock just didn’t ride the same though. Locked out was that – locked. But the open position was either too plush to be responsive, or too firm if the pressure was increased. So it was suggested that I try a custom Fox rear shock.
Simon Glanville the Fox Service Technician at Sola Sport in Sydney, knows the action of the Scott Spark, and the racing I was using my bike for. I left a basic Fox RP23 with him and he made some thorough changes.
1. It has an extra volume (XV) air can to lower the compression ratio to 2.4 rather than 3.0 with the standard (STD) air can. It makes the spring rate more linear as the bikes suspension system naturally ramps up.
2. A Firm Pro-pedal spring was fitted combined with a 225psi Boost-valve, this makes the pro-pedal platform very firm but still allows the shock to compress over high speed bumps or blow through its travel when needed.
3. Medium velocity helps give the shock midstride support as well as stopping the shock from being too regressive when the Boost-valve opens
4. Medium rebound tune keeps the shock under control for the given range of air pressures used with that suspension linkage.
Since having the newly tuned Fox shock onboard, the Spark rides how I wanted it to. I use the ProPedal lever to run it more open or with a lot of ProPedal, and using the Boost Valve for heavier hits. Now, the bike doesn’t compress heavily into corners, and it doesn’t feel like you’re just compressing the rear shock when climbing. There is plenty of suspension action there when needed for climbs. I’ve been surprised what I’ve been able to make it up, using the two main positions dependant on the terrain.
Of course, there are more settings than that on an RP23 rear shock. But the positioning of the shock on the bike means I just can’t see it well enough to use them.
The Scott Spark isn’t the all out race bike in their line up. The Scale fits that bill. But the Scale wasn’t really unto the rigours of Marathon and Stage Racing, as myself and other team mates put it through. With the change to the Spark, the 29er variant had lost the racey edge that I liked with a 26″ Spark (albeit, running a 100mm fork). By firming up the rear suspension, and allowing it to essentially react like the Fox Terralogic fork, I’d found a stable and admirably fast Marathon and Stage Race bike. Such a small part of the bike was able to change the dynamics from a bike I was reluctant to race, to one I’m happy to race and ride all day.
If you’re not happy with your bike, why not try a custom tuned shock? It’s cheaper than a new frame.