Is a 51cm frame road bike the correct size for someone almost 6ft? Looking for some advice on my first road bike.

I've had my eye on a Carerra Virtuoso for about 6 months now, they haven't budged from £350, however I've just spotted one on ebay second hand.

None of my local stores have this bike in stock, otherwise I'd go sit on it to size it up.

Being 5'11" (about 180cm) and 194 lbs, would I be too big/small for this bike?

I currently have a 22" Carerra Kraken and that feels about right size wise

Also, bearing in mind they are £350 new from halfords (and I have £50 halfords vouchers..), how much would be a reasonable bid?
From the website:


  Large bottom bracket to top tube = 51cm which is equivalent to our standard 58cm frame


51cm sounds too small for you; 58cm might be ok or it could be too big.  But there is no substitute for actually trying out the bike, or at least something similar to it.  Your leg, arm and torso lengths all have an effect on how well any bike will fit you and it's based on more than just the seat tube length.

Remember that a bike that's comfortable and fits you well will be more fun to ride.  Good fit is more important than weight or colour -- or even price -- so choose wisely.