FSA compatible??

No you don´t have to buy another octo. You have to buy an isis bottombracket. However FSA are also availiable for octalink bb´s so if you buy such a crankset you don´t have to buy aq new bb. So be aware of what kind of FSA crankset you´re buying isis or octalink.

I realise that FSA do both ISIS and Octo, however everything I have read indicates that the ISIS is a better option of the two, so what I'm hoping I can do is buy new bottom bracket in ISIS and still use my current Octo crankset until I have saved cash for the new FSA crankset (my bottom bracket is getting real rough and as it came with the frame and age unknown I'm going to throw it away).

Hopefully this makes sense??

Nope - if you're going to change one, you have to change both. 🙁

ISIS isn't compatible with the Shimano Octolink, since it has 10 splines on the axle instead of eight. I like it better because it's an open-industry standard, not proprietary to Shimano.

If you need a new BB anyway, I'd save up and go for the new ISIS set up so you don't have to mess with taking the crank on and off. Believe you'll like the FSA cranks and chainrings a lot.

Many thanks, that was exactly what I was hoping to find out, however I now need to save a little more from the wife (hopefully she won't notice :eek: )