While I have no doubt at all that the K series of BMW motorcycles are about the best in the business as far as reliability and longevity go in the motorcycle world, I would hold extremely grave doubts about the V twin series of Moto Guzzi's being better than any of the flat twin BMW engines.
I've had 14 flat twin BMW motorcycles, with many of them running around 300,000 klm's before I've moved them on. At the higher end 350,000 klm's was the go before they really start to fall apart, while up to 150,000 klm's is roughly the starting period of ancillary equipment starting to need severe maintenance or replacement. I have logged slightly over 1,5 million kilometres on BMW flat twin motorcycles on 14 individual BMW machines, then there are the other machines which take my motorcycling to slightly over 2,000,000 kilometres over a 53 year period of riding; I sold my last motorcycle last year.
I personally know of one R1100GS owner with well over 450,000 klm's on the clock, bought new and entirely maintained by the owner. While it is running very well, the maintenance schedule, which is normal for high kilometreage machinery is fairly intensive. The throttle bodies usually require a rebuild around every 150,000, I could go on, but that is the norm for any high kilometreage machine.
Guzzi's are pretty remarkable, but they do have their foibles. The V7 Ambassador (700cc) was able to run almost forever, but one had to be reasonably careful to not over tax it from a cold start, otherwise one could and did strip the chrome bore lining, don't ask how I know this. The next V twin model with a slightly larger engine capacity of 750cc was probably a better machine overall and as long as it wasn't flogged to death by high revs and hard cold starts one was fine. The 850cc V twin was picked up by some USA Police forces. They were terrific, except for when they were sitting on the roadside waiting for a speeding motorist. With a cool engine then a start up and high revolutions, the bores of these machines soon started to fall apart. I personally saw two of these engines from wrecked ex USA Police force bikes brought to Australia.
I rode a V50 Monza through Western Europe, it was the sixth (if my memory is correct) off the production line, the first unit is in their factory museum; which is certainly worth a visit. It was a brilliant machine and was ridden hard through western Europe then brought to Australia where it finally died with various terminal problems at the ripe old age of 170,000 klm's. Basically it was just falling apart everywhere. The best part of the Moto Guzzi bikes was their integral braking system, really good for what it was at that time in motorcycle braking development.
I could give you a timeline of what falls apart on BMW flat twins and what falls apart on Moto Guzzi V twins, within reason they are similar up to around 150,000 klm's, from then on the BMW's start to be better. I've never seen a V twin with over 200,000 klm's, although I have no doubt they are around.
I've travelled around Australia 13 times on motorcycles, and as for the notorious south road (Adelaide to Alice) in the sixties and seventies I lost count around trip number 20. That south road was quite a hard road to traverse in bad conditions, wet sand in the southern section would eat bearings, brake liners and brake pads and discs on the more modern machinery. While the very hard sections around Cooper Pedy in dry conditions made mince meat of suspension components.
Attached is a picture of when I stepped off after encountering very thick gravel and running out of power to keep the front wheel from sliding away. I was two up and as you can see, heavily loaded. Four litres of water stored over each cylinder didn't help, neither did the two spare tyres on the rear. Lost about an hour or so getting things running and patched up, then continued on for the next couple of months; as you do. South road north of Cooper Pedy.
The other picture was typical of the conditions found in many places in the seventies after rain, just mud, mosquitoes and copious sweat in the humid conditions. North of Blackall.
Mick.
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