Headset installation on carbon frame

[JasD]

Hi all,

I am rebuilding the headset on a carbon Cannondale Synapse and i am curious if i should grease the bearings where they touch the frame. All of the videos i have watched show a liberal use of grease at the interface between the two, but i remember reading somewhere that grease on a carbon frame can be bad (supposedly makes the carbon swell?)

Can anyone give some advice and suggest which grease is best to use assuming it is safe to use it?

Thanks in advance!

 

[accountantpete]

I don't know anything about grease damaging carbon.

Just checked a shop assembled Synapse and they used white lithium grease.

The top bearing has no grease outside but has a coating around the inner race/compression ring presumably to ensure a quiet interface (make sure you don't get any on the contact area with the steerer).

The frame is a year old and the outside of the bearing has begun to rust very slightly - so an annual inspection is probably in order.

Bottom bearing - grease around the outside and above the crown race (for water presumably) but none on the races needed apparently.

Hope this helps.

Pete

 

[JasD]

Brilliant, thanks a lot for the advice. I was sure the thing about grease damaging carbon was nonsense, but it seems safer just to check.

 

[Smokin Joe]

Brilliant, thanks a lot for the advice. I was sure the thing about grease damaging carbon was nonsense, but it seems safer just to check.

Most things you read about carbon are rubbish.

 

[mrseasons]

Curious - was the bike built by the shop a frame they had assembled? or was it a factory built bike that they just turned the bars and put the wheels in?

 

[JasD]

It was bought from Pauls Cycles. I think it was all originally assembled correctly but there was a bit of a gritty sound coming from the headset as i turned the handlebars (after a fair bit of use) so i just wanted to give it all a clean and reassembly.