Thank you for all your replies, some interesting and varied comments. The towbar was retrofit fit to my van and its the towbar manufactures that specify the max ball weight. Its a small van, too small for the bike to fit inside without a proper struggle. I love the dave cooper carrier, just to point out my concern is not with the rack, its superb and does a great job. I think its a case of what your happy with, for me I know for sure that the nose weight will be exceeded and although its strong enough to take the additional weight it opens up a can of worms for the insurance companies to wriggle out of if I ever needed to claim and I don't want that. So Ive decided to look for a trailer. Please keep your comments coming though.