The F650 (single cylinder) and it GS derivatives are a fun ride. Not as much punch as say a DR650, but more than enough for most circumstances.
My wife bought herself a G650GS as a retirement present to herself in 2016.
Lovely to ride on bitumen it was a nasty piece of work in more than shallow dirt or sand. The reasons aren't relevant here.
I started hating it a lot sooner than she did because I do the maintainable on our motorcycles.
To get to the airbox involved removal of around 16 torx headed bolts. This exposed the airbox ànd you could then remove the air filter, a tiny little thing that required removaland tapping out daily when touring on dirt. The retention system was completely Micky mouse and seemingly designed to let air and dirt past the mating surface.
The entire airbox needs the be removed to change sparkplugs, fortunately they last a long time.
The valve lash is by way of shim-under-bucket. To check clearance you must remove airbox, plugs and throttle body to get at the valve cover.
In the unfortunate event you need to change a shim then your fin has just begun. The cams have to come out and the first thing you need to do is wind in the special bolt to lock the crankshaft.
Then, if the bike is equipped with ABS you ne d to completely remove the ABS pump and it distributor pipework so that you can remove the cam chain tensioner and then the cams
Re assembly is the laborious reverser. Oh and you need either a HS911 or a motoscan setup to run the ABS pump to bleed the brake lines. Apparently you can supposedly bleed the brakes without running the pump, but I dread to think how long it would take.....
No let's move on to something that should be simple, but isn't. T check the oil level you need to do so immediately after a ride with FCAT least 10km or leave the bike idling for 15 minutes. Why? You may well ask. Because it is a dry sump engine and you need to check oil when it is hot and as few seconds after shutdown as possible.
FFS! Even the English could design a dry sump engine that would keep all the oil in the catch tank for at least a few days. The 650 takes around 10 hours to empty the tank into the sump.
Forget to check oil level quickly will result in you thinking the pop is low and then overfilling. You do not want to experience what happens next, oil sprays everywhere!
Changing the oil is yet another bastard of a job. If you dump the oil with the engine warm you have to unbolt the oil tank and drain it. I only played that game once and changed the oil with a cold engine thereafter ,- afterall the pip which uod be in the sump which obviated the stupid unbolting and draining of the oil tank.
Now it is time to drain the oil. BMW fitted an alloy, low heigh sump plug -bastards!
The semi evolved simians at the dealership had done a good job of rounding it off at the first service. I replaced it with a steal one.
And now the filter..... Undoing the bolts to free the filter results in around 100ml of used engine oil down the side of the engine.
Yet another example of brilliant design - not!
Eventually I made a chute from a piece of plastic water pipe to prevent this particular oil spill.
I don't know about the road bike but the GS version eats the bearings in the suspension rocker - so badly that I checked them every oil change.
But, as I said, on the road it was a fun ride and managed in excess of 300lm from its tiny fuel tank. The twin spark engine is the pick of the bunch, it is a little more pokey than the single spark models.
The engine management is by Werle and although our gave no trouble but YMMV.
I have never been so glad to wave goodbye to a bike as that one!