Hi all. I have an old mountain bike that I love and I am doing it up a bit. I need to replace the chainset, because the teeth are knackered. The problem I have is that I can't seem to match the teeth ratio with any new chainsets out there (46, 36, 24). There are ones available that are distinctly similar (e.g., 48, 36, 26), but they are called 9-speed chainsets and I believe my current one is a 7-speed chainset. My chain is also designed for 6,7 and 8 speed bikes. Can I use a 9-speed chainset with this setup? Any help would be greatly appreciated. Many thanks, Matt.