This is a service to re-profile your head to a 93cc combustion chamber.
We machine the heads with a small step so that they can be run without a head gasket.
If you are moving from a 50 to a 93cc bore and do not have the head machined in this way then you will be doubling the compression ratio as well as not having a decent combustion chamber shape and it will be broken next to instantly.
You must however check your squish clearance is correct upon assembly and adjust as necessary.
For customers outside central Europe it may be worth getting in touch with us to see if we have or can get hold of a head here cheaper than sending yours to us from abroad.
PLEASE NOTE: If you are sending your head from abroad either put the customs value at less than £15 including postage and / or mark your package very clearly as 'For temporary import for repair and return'
Any customs charges cannot viably be recovered and you will become responsible for settlement of these charges.