Rear shock modifications on a Manitou Swinger Coil Over
involve disassembly and the removal of the stable platform valve
altogether, a standard shimmed piston is introduced, rebound and high and
low speed adjusters all remain effective.
Please note that my personal differences
concerning high and low speed adjusters are quite negative, I fail to
believe that the small orifices can cope with large amounts of oil flow,
and although these adjusters might be effective at low shaft
speed they don’t assist where it matters most.
HSC performed the modification and mounted a non SPV
damper on a Transition Bottlerocket, test rides so far have been
positive.
Although the Transition Bottlerocket probably isn’t the
ideal design to test modified rear shock dampers, the non SPV Manitou
shock performed as well as any of the popular designs
available.
And to keep the observations honest I regularly changed
the modified damper out for a standard SPV Manitou, keeping spring weight,
preload and damper adjustments identical with the exception of pressure
differences in the IFP reservoir ( I used higher pressures in the non
SPV damper ) Instantly noticeable was the non SPV dampers low speed
compression, it was a far more supple ride over small bumps, and rear
wheel traction appeared to improve over an SPV damper. Note, test pilots
that rode the bike with the non SPV damper were unaware of the
modifications and the initial response from both riders was positive, with
testing I chose random times, this allowed me the time to swap out dampers
without the knowledge of riders, and their first reaction on riding the
same bike equipped with an SPV damper was that I was accused of increasing
the spring rate, even though it was clearly marked on the coil
spring.
My own thoughts on the non SPV damper were always
positive, I enjoyed the ride and have never warmed to SPV, but having said
that one of my bikes is a Foes 2:1 DH Mono, with a long 5 inch
stroke Curnutt producing 10 inches of rear wheel travel, and I find the
bikes performance and rear shock action quite different to the
smaller brothers like Manitou and 5th Elements. I can vouch for these differences in the Curnutt as I’ve owned pre
2:1 Foes using Curnutt shocks in the past. I will however mention that a
two to one leverage ratio will mask the characteristics of a Stable
Platform Valve on low speed compression, and I remind the reader that the
Curnutt design and Stable Platform were not designed with
preventing bike rider induced movement as the priority, but to
inhibit the unnecessary over travel of dampers in off road vehicles
with large amounts of suspension.
