Motivation:
As I've mentioned on other threads, I weigh 175 pounds (with gear), I found the stock suspension harsh and lacking compliance over bumps (even after setting sag and twiddling the damping adjusters), so I had my forks reworked and got a Penske shock. I'm much happier with the ride now.
I writing this post primarily to pass on what I learned from the regarding the stock suspension from Phil Douglas, at
Aftershocks Suspension, in Palo Alto, California.
Fork Springs:
Triumph describes the stock springs as dual-rate progressive springs. Phil said that the windings were all too widely spaced for any coils to fully compress, even at the limit of suspension travel, so they are effectively straight-rate springs. He found the rate is 0.89. He modified my springs to 0.95 and cut 8mm from the internal preload spacers, to get a final sag of 35mm with four lines showing on the preload adjusters.
Fork Compression Damping:
Phil thought the harshness I complained about was a result of the compression damping. In particular, he thought the point at which the oil entered the high speed circuit was too late, so he changed the shim stack to allow the oil flow to transfer to the high-speed circuit sooner. His view is that Showa designs the compression cicuit as it does to work with the soft springs, to prevent bottoming.
Shock:
Since I swapped the shock myself, I didn't learn much about the stock shock. I know the Penske (model 8983) came with a 900 pound spring and that it required slightly less preload to achieve 28mm sag than did the stock shock. It's considerably more compliant and (of course) the ride is very well-controlled.
Result:
I think the improvement in the shock is more significant than the improvement from re-valving and re-springing the forks, but both were well worth it. I hate a harsh ride! The cost of the fork work was $310; the cost of the shock was $795. Since I removed and re-installed both the forks and the shock, there was no labor charge.
Linear Mode
