Hard Start
Check the compression. 135 to 150 is pretty good for a used 900. They should be even.
Check it warmed up.
Before you try and start it WARM look at the plugs are they wet ?
Flooding or no fuel ?
If no fuel remember the Mag must fire the fuel pump but if it starts cold thats most likely not it.
New Plugs ?
Plug Boots should be changed about 1000-1500 miles.