I went from Onza Orbitas which are short? 160? it was short anyway... Went from them to the new Echo ones which are 170, and yeah, feel reallly weird for the first few times you go on it, but also feels better at the same time If your running a fixed cog on the front, I think any ISIS bb would be alright. I run a Echo external bb, with the cups outside. But if your going to run FFW i dont think you can run it with an External bb cos the cups will get in the way. If so, get internal bb from Echo Hope that made sense