Hi Marty:
Have a look at posts #120 through to 126 inclusive in the following post:
ST1300 - Solving the Coolant Leak Problem... For Good. Those 7 posts form an illustrated "how-to" story explaining how to tighten all the hose clamps on a ST 1300 without removing the fuel tank, throttle bodies, etc. You can skip the first 3 pages of that discussion (except for the last post on the 3rd page, which is #120), because the first 3 pages consists of talk about alternative hose clamps, the installation of which will require a huge amount of disassemby (and financial outlay).
I did exactly what is recommended in those 7 posts by forum member '4Jranch' 2 weeks ago, and it has solved all my coolant leak problems. You will need to go buy a jug of Honda coolant before you start, because removing the radiator to access the clamps implies draining all the coolant, but coolant is cheap and it has to be changed every 2 years anyway. Since you probably don't know when (or even if) the coolant was last changed on your bike, it fits in nicely with solving the leak problem. It took me about 5 hours to do everything, beginning with Tupperware removal and ending with going for a test ride.
Michael