Where I heard is from an F800GT thread on ST-Owners.... so I'll just copy from a longtime owner.......
" Just stumbled on this thread. As Mellow and some others have mentioned, I do have one and love it. I have 94,000+ miles on the bike now and will turn over 100,000 by mid-summer, easily. It's been trouble-free.
At your height, I'd check out the motorcycle ergonomics web page. You can play with a lot of variables and put two tabs on the screen to compare what you currently have with your ST and what the GT will give you. There are lots of options for ergonomics, and you might even be fortunate enough to find one where someone went through the expense of modifying it for you. For instance, you can raise the handlebars and adjust them forward and back. Mine also has lowered footpegs. And there are five different OEM seats and aftermarket cushions you can add. I have a Madstad windshield...it is phenomenal.
Power is an interesting topic for me. It has less power than an ST...but also considerably less weight. I kept up with some extremely fast riders on Kawasaki C14s, a BMW K1600 and an ST1300 through Oregon and Northern California the summer before the lockdowns. Their bikes were all putting out around 150+ hp at the rear wheel. I had no problem once I decided to through caution to the wind. In fact, after about 10 am, they were easy to "reel in" because they were getting tired flinging all that weight around.
Below 4000 rpms, the bike has plenty of torque to do what you want in traffic. You're not going anywhere, so why make the engine scream like you might? Above 4500 to redline, it is like Dr. Jekyll and Mr. Hyde. It's a totally different experience. You want a nice relaxing ride...stay in the lower portion of the rpms. You want to keep up with anyone...let the engine sing. It'll put a smile on your face.
The bike gets pooh-poohed by some reviewers. They think it is underpowered. I think they are fooled by one factor on a bike like the FJ-09 standing out, and focusing on that while forgetting the rest of the experience. The F800GT seems tame in comparison. When I took the bike out on my first long day trip, I found myself doing 90 mph in a 55 zone. I wasn't trying to speed at all. The bike just seemed so relaxed. I thought I was only doing about 60 mph. I think it is amazing that BMW was able to make a bike to meet a cost point...and make it so well.
BMW recommends replacing the belt at something like 25K. I'd recommend buying one at 25K and then keeping it on hand till you need it. I replaced the first one at 53K. It obviously can go farther. Also, with the bike being out of production now...parts that you could only buy at a dealer can be found elsewhere. The belt used to be around $525 from a dealer. I found my last belt on Amazon from Continental for about $120. It's not a shaft drive, but when I pull into a motel parking lot, I don't have to worry about lubing a chain.
The GT is the successor to the F800ST. They are not the same bike, though very similar. BMW actually listened to the owners and incorporated their suggestions to the "upgrade" The ST had some electrical issues and rear wheel bearing issues. That all seems to be fixed on the GT. I've replaced the belt twice now, tires, brake pads and fluid, and obviously oil. That's about it. It's been trouble-free...and easy for a non-mechanic like me to maintain. I've checked the valves twice (paid for that

) and found they haven't changed. I won't bother again. Taking the panels off, is a breeze. There's nothing hidden to break.
I do about 14-15K a year. Miles, not kilometers. I would have no problem taking the bike cross-country tomorrow morning. The only thing I'd consider first, is if I need an oil change. Otherwise...the bike has been dependable without needing to baby it. I think it is the most reliable model BMW has made.
The only difference between a 2017 model and my 2014 model, is "ride-by-wire". All the same components are there, it is only on how it is controlled. If I could get a 2017 model, I'd go for it. The basic bike is the same, and I'd buy anything from 2013 on.
If you have questions, just ask. If my current F800GT dies for some unforeseen reason...I'll buy another. "
Entire thread is here if you have access....
Saw one of these for a decent price and stupidity low mileage. Very attractive at 200lbs or so less than the old ST with a tad less power but thats no big concern on my part. I am wondering about seat height and knee angle for comfort, the bike ergo site seems to suggest the GT is 1” higher at...
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