Advice on fork upgrade

[Timotheog]

Hi all I have a Specialized Allez C2 2014. And would ideally at some point like to upgrade to a carbon fork. I understand the allez fits a 1-1/8" but what size does the rake refer to? One I've been offered from a tarmac has a 45mm, would this fit?
Excuse the ignorance of my question, I searched and couldn't find anything.

Many thanks

 

[accountantpete]

The rake is the distance the fork drop outs sit ahead of a perpendicular line running down from the steerer - ie how much the forks are angled forward.

There are various rakes for individual preference but 43mm is about the norm.

You will need to check the steerer on the Tarmac though. I think you have a tapered steerer so you need to check whether the Tarmac is the same and that it is long enough. If it is a carbon steerer check there is no wear from the compression ring towards the top of the steerer.

 

[Timotheog]

That's really helpful thank you. I wonder if the 2mm would affect things? The fork is a new one. I am a bit cautious though as I'm not sure about whether the steerer length is any different.

 

[accountantpete]

I wonder if the 2mm would affect things?

It shouldn't - presuming the existing fork is 43mm. The only real downside to the whole process is if you get a much "straighter" pair of forks than the existing ones and suffer from toe overlap when turning.