Very bad idea, you would never own the bike and you would just keep paying for eternity like renting an apartment or house, in reality who needs a new bike every 3 years? that's silly, no, that's insane. And just like cars I'm sure they'll nitpick every tiny bit of damage and charge you. In the long run, actually in a very short run you'll end up paying a lot more for the bike(s) than the person that buys their bike. This sort of thing appeals to low income people, which is why you find furniture and appliance rental stores in low income neighborhoods along with payday cash places.
You can't make any changes to the bike; and how will they depreciate the value of the bike as miles roll on? I wonder if they'll install some sort of GPS system to keep track of the miles? They can then charge you for additional miles that you go past a preset limit.
If you can't pay for some reason, they'll want your bike and ruin your credit. So now what? try to find some other sucker who will take over the lease payment?
You might as well use your money to wipe your arse with! Lets say customer A leases a bike that cost $5,000, and customer B buys the bike new for $5,000. Customer B could either sell the bike and take the money and buy another or keep the bike indefinitely, customer A can't sell the bike because it's not theirs, if they decide to keep it indefinitely they have to buy the bike a SECOND time! Leasing, or renting, is 100% liability.
Read this, it's about car leases but it's the same thing; see:
http://www.moneyunder30.com/why-you-should-never-lease-a-car