Hi, I used to run a hire company and offer bike hire on the island during the TT, there is limited hire on the Island, modern bikes are very expensive otherwise there were some old BMWs, for a  big group I doubt it would be worth it or do-able check out Jason Griffith's website. The other alternative is to hire 'across' but then you have to try and get ferry crossings too. You might have a word with Bill from Bike Tours Uk he has been taking groups over for years and is sound, he block books ferry tickets gets your kit across and camping etc - he no longer does bike hire but he will give advice and at least you could get across all together. You might check out Hunts in Manchester who hire out their sales stock.

You could buy a bike here but you need insurance to register it and tax it and can't take out uk insurance unless you are a uk resident with a uk address, you can bring a foreign bike with foreign insurance. Beware of anyone saying you can be 'put on' someones insurance you can't and you won't be covered. I have direct experience of some Ausssies who all gave their mates address in London and came unstuck. Also check that anyone hiring out has proper hire insurance there are only two hire insurance companies in the uk READ the policy carefully, I know of at least two hire companies who didn't have proper insurance or ignore the insurance requirements. The proper hire  insurance won't cover loads of occupations such as models, actors. proffessiona,l sportsmen etc but more relevant 'anyone involved in the licensed trade - I had to refuse a party who worked for a Coors distribution warehouse in the US. Its all very well blagging your insurance form - but you won't be covered and the Island is no place to be uninsured.

Some Canadian licences don't show you've had a full licence for the required period so you have to get a certified abstract of your driver record from your licence office.

Strangely some EU countries allow 3rd country nationals to buy and insure a bike for travel anywhere in the EU so that might be a possibility but you have to check they would cover the Isle of Man which isn't in the EU but has various insurance agreements - also of course its the added agg of an extra ferry crossings and distance.

One thing for sure everyone of my customers who made the effort from around the world were absolutely blown away, many just couldn't believe that the whole thing is actually legal, sell a kidney if necessary there's no need for a bucket list after you've done a TT.