Mine rattled like hell til I replaced the springs and oil, and then it stopped. No idea what caused it but I suspect it was the thicker oil that stopped it, can't see why it would be the springs. But then there's loads of causes for a front end rattle, some people blame the discs or the calipers, others the clocks or the headlights, some have found it was their head bearings...
If it's any consolation, I replaced the entire forks with GSXR ones and now I have a mudguard rattle which is worse than the SV one ever was, because I'm using the wrong mudguard
