There are a number of operators now offering bike  hire on the Island try google but be careful that they are using a proper hire insurance company - one that does is Jason Griffith ex racer who has a shop near Braddan - I think its £190 a day ish but hes probably booked up. Also make sure you comply exactly with the Licence requirements, bring all the original docs. It was amazing when I was hiring bikes how many people just didn't listen to instructions or forgot to bring the correct stuff only to be turned away and lose their money.

You're probably best off on the trike tour as riding on the Island is very different to the US and I found that most Americans struggle to adapt with some unfortunate consequences - a one day hirer wobbling round the course on the 'wrong' side of the road isn't very enjoyable for anybody.

Another idea - Barry Wood ex racer is a Taxi driver get a couple of others and hire him for a lap I'm sure he'll give you an interesting time.