Ignitor box.
Headlight.
Final drive.
Seat.
Tac face screw.
Horn button.
Bought new in Japan during my Navy days. All the reviews of the day were positive. They were close, but couldn't know how great a bike the 850 truly is.
At about 7500 miles the pumpkin (?) went bad. Suzuki has an excellent record of driveline reliability so I asked my mechanic what happened. He thought it was due to poor assembly (I had it shipped from Japan and put together by a shop in San Diego that has long since been out of business). Since then it has been trouble free. The ignitor box failed in 1996. A factory replacement set me back about $400, but for as many miles as it has had to endure, and all the years it sat outside, I can't gripe.
The seat pan has rusted itself into two pieces. Sitting in the weather with a ripped seat helped it along.
The horn button broke. The little plastic button itself.
A screw holding the tac face has backed itself out and rolls around the bottom of the instrument face.
Been through a few headlight bulbs over the years. Not unexpected. But the reflective inner lining of the headlight is peeling making the light less effective.
The shim under bucket valve adjustment is not nearly as easy as the adjuster screw set up of my GS700E, but that's about as harsh as I can be concerning maintenance. Newer motorcycles have eclipsed the 850 in every measurable respect, but not one (in my opinion) has put it all together in so satisfying a way.
The 850G may not have flash, blinding speed, or brick wall braking, but it will keep you smiling like a fool long after you SHOULD have stopped riding.
I live in Tennessee and bought my 83 Suzuki GL in 1984 with 600 miles on it, and now, in 2007, have 18000 miles on it.
I have taken it to shop only for tires, no maintenance, and have only had to replace the headlight bulb 3 times. It's built like a tank and so reliable, and rides just great. I am 66 and am sure it will outlast me by a long-shot. The only other bike I had that rode this well is the 1956 Triumph Tiger 110 when I was in high school, but the reliability of it was no match for the Suzuki.
I can't bear to part with it, but my wife says I cannot have it buried with me when my time comes.
Update to my original post. I have since purchased an '83 850 off off eBay that was in great shape. Super low miles. It rode like I remember mine rode when it was new.
I swapped out the tank, saddle, instruments, shocks, front fender, headlight, etc. The same as a cheap rebuild, but with all the impossible to find parts in one easy package. Now I ride my old faithful mount looking/riding better than it has in years, and my buddy has himself an ugly looking, low mile 850 that's good for 100,000 miles or more.
1983 GS850G - Always a fan of the GS series, this is my 3rd. All it needed at 25 years and 38k, was the brakes bled and the rust taken off the tank and painted. (Took about 5 hours total) Very reliable bike, fun/easy to ride, and plenty of power. Always a recommended series, the GS line is AWESOME.