headset stiff

Hi
My headset is a bit stiff on my lapierre(poxy french crap) X-control 513.
anyone know are they hard to replace?and any links,ideas etc to a suitable replacement.
making best use of poxy chest to get bikes ready for some serious action.
Cheers
easy to replace. chances are it has sealed bearings. just take the code from the side of the bearing and get a replacement from a brearing shop. CRC also do most bearings. as do ebay....
all the lapierrres use a semi integrated headset. Not a standard cartridge bearing. You can have a complete new headset from 30-35 euro.