I have the carrera vulcan it has the Clarkes exo hydraulic brakes.I what to swap the clarkes for better ones so will the Zee M640 fit my bike if not what other braks will fit my bike
Shimano Hydraulic brakes are often sold as a kit, with the hose already connected to the caliper and lever and the system already bled. These kits are listed according to which hand the lever is for (the front brake's lever can be on the right or left according to country and preference) , whether the caliper is intended for the front or rear (the caliper body is usually the same but the fittings can vary) and hose length (to allow for different frame sizes and suspension designs/travel).
The lever clamp is almost always about 22.2mm (7/8th inch).
The caliper mount on the frame or fork will be IS-mount (bolts from the side) or post-mount (bolts parallel with the rotor). M640 brakes are natively post-mount.
Adapters are available to fit PM calipers to IS mounts. Adapters are also used if a larger rotor is used. The normal rotor sizes for calipers without an adapter, or using a "+0mm" adapter for mismatched mounts, are 160mm at the front, 140mm at the rear.
As @Batman says, 'Sure'. If your Vulcan is the current model, then your front is post mount (PM) and the frame is international standard (IS). The mounts with your Clarks brakes might work, or they may strike the caliper. New Shimano brakes unfortunately do not come with IS mounts so you might have to buy a Shimano mount if this is the case.
Could I ask what you use the bike for, the Zee brakes are twin piston DH brakes so they're fairly powerful and not commonly fitted to a XC/trail orientated bike like the Carrera Vulcan. You may find that Shimano's SLX or XT brakes provide the stopping power you need but at a lower price point! Merlin Cycles always have some of the best deals on prebled Shimano brakes.
Most prebled brake systems have an abundance of hose, so you'll likely need to shorten the hoses unless you wrap the excess round the stem once or twice.
Hope this helps!