I’ve just got hold of a pair of SID XX world cup’s.
Apart from obviously torquing up the stem correctly, do I need carbon assembly paste for the stem & steerer?

I would definitely use paste and follow the fork instructions regarding torque not the stem ones as the stem ones will normally assume a metal steerer.

You’ve got the expander wedge I assume?

Not a vast amount else to know, I never used assembly paste on any of the carbon steerers I’ve had.

Just wanted to mention my name is Stuart and I was born in 1972 🙂

You don’t really need it tbh. Some(trek) recon you should never use paste on a carbon steerer tube

Trek dont recommend assembly paste on steerers in fact they issued a technical bulletin regarding this

I know of another manufacturer who are also doing the same research into frames with regards seatposts and failures of frames

the bulletin: http://thegoldenwrench.blogspot.co.uk/2011/09/tech-bulletin-from-trek-regarding.html

tbh I had not through about the paste getting down to the compression ring but it makes sense.

With regards to other problems I wouldn’t be surprised if some problems were caused by people using too much. In a way I don’t like using it as it is damaging the surface of the carbon fibre but it does make a difference. Have seen quite a few carbon parts coming with a rough coating applied which prevents the need for paste.

tbh if there is a risk of fretting of parts on the carbon steerers (or any other part) they should be suitable protected by even something as simple as a urethane clear coat.

Had a dig about in the Rockshox manuals and interestingly they don’t quote torque settings for the steerer. They tell you to refer to the stem manufacturer.

Looking at the Thomson x4 info it reads like 5nm is the torque whether it’s carbon or aluminium?

The forks do have the original expander with them btw.

Out of curiosity, is a Hope head doctor OK for carbon ?

if they say refer to the stem instructions then you are covered. Double check the Thomson wesbite to see what they say about carbon steerers – ie check everything for your own safety and warranty purposes!