right i'm trying to get my cylinder off but no matter what i do it won't move please help thanks.

You have to take the head off first.  

sorry couldn't resist.

Sometimes they stick pretty well, especally the first time. I like to take the end of a 3/8ths extension and tap against the bits of the cylinder that overhangs the case (NOT THE FINS!!!) and tap on that until it comes loose.

Sometimes I have to use a screwdriver to lightly pry it loose. Make sure you are against a solid part of the cylinder not the open fins. Pry it evenly from both sides. Once it is free from the base you can wiggle it remove it.

just tryed that and still nothing it's like some used superglue or liquid metal to put together lol i've just whacked like a hundred times with a rubber mallet as hard as possable but nothing.

I just swapped cylinders a couple of hours ago. It is possible that there is coppercoat (or similar gasket spray) on it. It will be harder to remove it there is. The indexing pins do not allow it to lift off at much of an angle. Try tapping a screwdriver between the cylinder and case evenly from both sides. This should lift it up.

Geez, don't pry on the fins with a screwdriver.   Bap the cylinders with a rubber mallet.  That's by the book.

i've just tryed and there isen't enough space to get a screw driver between them is there anything else i got it to lift on the intake side about half a mm and sprayed some wd-40 between it and i'm going to leave it over night and see what happens.