I refurbished my 1991, completed in November 2020. Replaced all hoses (water, vacuum, air, fuel), rebuilt the carbs, new thermostat and cap, replaced the exhaust, fuel tank and all components, installed handlebar risers, rebuilt the master cylinders, cleaned touched up paint under the fairings, filters and fluids of course. Just added up the part cost, $1929. This doesn't include the cost of going over it got when I bought it in 2015 which included replacing the timing belt and other iffy looking parts I encountered there. (edit: just added up.....the first refurb used just over $2300 in parts) There are several ST1100 refurbishment articles if you care to search on them....they highlight the task from several owners' experiences. Still has the 28 amp alternator, I found a spare from a very low mileage crash victim at a bike wrecking yard. Unless you get lucky also, it's probably a good idea to at least collect the alternator upgrade parts. Most of the work I did was due to age related issues.
Nearing 23,000 miles now. It was decently cared for, not abused by the PO. Kind'a hard to abuse it when he didn't ride it much.


Reviving dead bikes has been my number one hobby since the mid 1960's. Mechanically, the ST1100's are more durable but many of the frequently replaced parts are drying up. It isn't practical for many folk to do this but, as you may suspect at this point, save the whales.