Hi thanks for that i hope one day to try the beast dont know how long it will be before im able to tackle that,one question i have is people go on about average speeds roughly what speed would i probably be at when i first start, i know that is hard to say really but i am 39 would class myself as fit, but that will probably mean nothing on a bike if i was just going at a steady pace what would that be at roughly
Average speeds are subjective and much debated here. So it depends what you want to get out of measuring average speed. Often the question is asked by people who are nervous about joining a club or worrying about finishing last at something. I have a friend who does triathlons and has finished last/second last a few times and could not give a hoot. He has a great day out with his mates and does not care about others opinions. I respect that.
In your area I know a 53 year old who can average 27mph over 10 miles. I do about 24 mph in local tt's and triathlons. Longer distance events over 100 miles I average about 19 mph. But on my long slow miles it can be in the range of 13-15mph with Mrs Gere.
You are correct in stating that general fitness and bike fitness are different. You need sport specific training to improve.
So at 39 and relatively new to the sport, assuming you are not overweight and no injuries/illness you should be able to knock out 15 mph in no time. But Durham is not flat, it is one of the toughest cycling areas.
In a season you should be able to get that up to around 20mph over shortish distances (5-10 miles) with some training.
skinnydog1973 and 
should only be ridden in good weather - being of Italian origin, they don't like water ... 
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