Quote:
Originally Posted by sharky nrk
I think the answer is almost always "it depends" lol. I mean your weight, riding style, other mods, etc all will dictate whether its an "improvement" or not for your particular application.
On the track, that 5mm difference is a BIG DEAL. I have the shorter dogbones and if your considering the GSXR shock for track work, getting that rear geometry change back is a must.
On the street for commuting/regular riding purposes....I suppose if the spring was in the right range and you had the shock adjusted properly it could be better, and certainly the adjustment flexibility is nice. But a "better" / "more adjustable" shock that is well out of range for the rider/riding style is not a "better" shock at all  |
I think this is precisely it. The '06-'09 GSXR600's spring rate is nearly identical to the NewGen/300 stocker (I'm not sure if that's a carefully researched feature or pure coincidence). However, most signs indicate that this rate matches a ~215lb rider. Also,
other GSXR shocks have a variety of spring rates. Depending on exactly which GSXR shock you buy, you may or may not be matching the stock spring rate, which may or may not work well for your weight.
I've seen very little mention of the NewGen/300's relatively stiff rear spring (I brought it up in another thread). If the rear can't properly absorb bumps, especially with too-soft fork springs, it'll bounce around like a rocking horse. If you're replacing the crappy, way-off stock parts with better, way-off donor parts, I wouldn't expect much improvement. The fact that they're better parts might even exacerbate the fact that they're mismatched.
Shock Swap Myth points out some issues with swapping in a shock from some random bike. There are many ways to skin a cat, and Suzuki's way might vary greatly from Kawasaki's. The GSXR shock is made for the GSXR suspension, not the Ninja suspension. On the other hand, they seem to be close enough that many people are very happy with the GSXR shock swap. If you're starting with bottom-of-the-barrel non-adjustable parts, it's not hard to find something that does work better, even if it's not perfect. If you can spend $35 and get a drop-in shock with better features and a good spring rate, that sounds like a great value upgrade (even if you spend another $35 on a second shock to get a donor spring with a better rate). I've personally used multiple shocks from other bikes on my 500, and been very happy with the results given the cost. If you spend nearly $500 trying to make that wrong shock into the right shock, you're now into the price range of good aftermarket shocks, and most likely will still be ending up with something not all that great.
I think it's around 3:1 for height changes at the shock compared to the axle. So the shock being 5mm shorter equates to the rear end being over 1/2" lower. While I'm sure it's a much bigger deal on the track, it will still affect the steering on the street too. It'll just be slower to turn and feel less flickable overall. While I'm sure a pro racer wouldn't just toss in a different shock like this, the 5mm difference shouldn't alter the angles in the suspension geometry much, and the rear height can be corrected via dogbones (R&T said above that even stock is too low anyway).
Overall, I think this can be a budget way to get a decent upgrade. Depending on the specifics of your mod, it's possible to do things in a way that will actually make things worse though. If you do some research and/or testing, I think you can end up with something quite cheap that will perform quite well.