my carbon seat post is far to long
would it be ok to cut it down
or would it weaken the carbon

As long as you observe the same minimum insertion length then i dont think it would be a problem.

You would be best checking with the manufacturer though.

It'll be fine. Sharp blade, file down the edge.

Thats a topical dillema – I am just about to cut down a broken carbon bar – Previous posts here suggest its OK. I am going to use some oil as a lubricant and a fine hacksaw and stem cutting clamp to get a smooth straight cut – I think as long as you dont use a saw too fast, hard or with too big a teeth should be OK!

Unless the length is stopping you getting the saddle low enough, why bother cutting it and taking the risk? One day you might be glad of the extra length (Fnarr-fnarr!) if you swap frames…..

Leave it as it is!

Unless the length is stopping you getting the saddle low enough

I am guessing that's what he means by "too long"

its that i have got an intense uzzi dh and the carbon seat post i have is about 6" to long
i will be using a fine blade on a bandsaw
i was just wondering if the fibre's that will be expossed after will need sealing with something like a fibreglass resign