While there are variations in how bikes sit on the side stand, your suspension settings have something to do with this issue too. What year, model, (ES or Std), Super Ten do you have?
Has it been lowered or fork legs moved up in the triple trees?
What's your pre-load set at on your rear shock? (how many clicks from all the way out?)
Generally speaking there are more Super Tens with the opposite issue, leaning over excessively, than ones that stand up strait too much.
The short answer, if you've not lowered it or moved the forks, is to crank up the pre-load on the shock some more.
The longer answer, after doing some investigation and trial and error checks, is that there are adjustable side stands you can buy and you can shorten the OEM side stand by cutting it and welding it back together. The Gen I side stand is steel and easy to work on for just about anyone that welds. The Gen II side stand is aluminum and will require some special welding equipment to re-weld. The side stands interchange, so some people will buy the Gen I side stand, (cheaper), and have it cut down to work for them, rather than having the Gen II stand cut down.