Rubber parts like this, especially when they are around high temperatures and excess vibration don't last forever. To ensure vibration does not find it's way to areas of your bike it is not supposed to, regular replacement of this muffler rubber will pay dividends in the long term, by avoiding damage to much more expensive parts. For other anti-vibe rubbers that may be past the first flush of youthfulness, try browsing our online catalogue, or where applicable the online 'parts list' fiche?