Orbea Onix BB

[hondated]

Evening all. I have just spent hours Googling this problem and I am still not sure I have the answer so I thought I would ask you all.

I want to upgrade my chainset from a Gossamer to an Ultegra but of cause I have suddenly discovered that they are two different sizes so not as easy as I thought it would be.
What is causing me a problem is that the outboard bb fitted looks like a Shimano one and to me it looks like I will be able to just remove it and replace it with a Shimano Ultegra one. But then I read that its not possible and I will need to get a converter to fit it.
Is that correct and if I do is it possible to fit it myself rather than take it to a shop and incur more expense.

I would appreciate your advice on this. Thanks.

 

[Citius]

Both use a 24mm spindle, so the swap can work, as both are interchangeable in principle. Although assuming you are talking about FSA MegaExo cranks, just use a HT2 BB in place of the MegaExo BB. You don't need a converter as such.

 

[hondated]

Thanks Citius for information and responding so quickly.