Agreed. Although I am not sure about the sizing of the chain, those fitted as OEM on the F650GS single cyl were pretty much rubbish - mine was replaced with Renthal sprockets complete with a new chain.
It goes for lots of manufacturers of course; stuff fitted as OEM is often purchased by the accountants, not the engineers.

__________________
Dave

Absolutely nothing wrong with the KTM. The bike is used almost exclusively for trail riding and probably only done about 800km on tarmac. The terrain can be very rocky and I've probably been unlucky - all 3 breaks have been broken side plates which have been repaired with rivet links, not at the roadside because I didn't have the parts with me at the time. I'm still using the original chain but did fit a non O ring chain for a while (whilst waiting for parts) which also broke.

Early failure of the shaft on my R100GS was probably due to a 30,000 mile trip around Africa 2 up with 95kg of luggage.

Apart from breakages the chain is quite easy to live with. I brush on chainsaw oil before every outing and hardly ever adjust it. I certainly wouldn't hesitate to take a chain drive bike on a long overland trip but I'm more likely to take the R100GS after appropriate servicing, as mention before, just because it's my favourite

In 1000000000004 miles (ish) of riding all types of bikes over all types of terrain, I have never had a chain snap.

I've seen snapped chains. It's always poor or incorrect fitment. Usually where someone hasn't peaned the link properly or peened it so tight that the chain can't flex properly.

It happens when you abuse it too (Like anything). Running badly worn sprockets can do it or having a rediculously tight/loose set up.

If you fit the right chain properly and replace your chain/sprockets when they need replacing then you won't ever have a chain snap.

__________________
Did some trips.
Rode some bikes.
Fix them for a living.
Can't say anymore.

I'm a fan of chains for all the reasons that people have listed. But they do need some thought on long trips.

My rear sprocket after 26,000km and no I hadn't taken a spare - and just because a bike is common at home it doesbn't mean it is at your destination. This is from a KLR 650- common as muck in Australia, but harder to find in Europe

Attached Thumbnails

 

__________________
Martin

finally back on the road again


http://awayonmybike.blogspot.com/

hi if you scroll down to Additional Options, click on manage attachments then browse to find your pics, double click on the pic and they should upload, you can upload up to 5 ,then click the upload box and they should be on your post , hope this helps steve

An individual case, either caused by a user error, or even a manufacturing defect, can always be possible. But for me, chains snapping is not a valid argument here. They just don´t do that under normal circumstances.

I'm not disagreeing with either of you. There is definately no element of incorrect fitment or user error in this situation and I'm happy to put it down to bad luck. I can't think of anyway in which the user could aggrevate the failure of a sideplate. I get good use out of chains and sprockets but don't run them until they are worn out.

All I am trying to point out is that chains can be unreliable as can shafts but it is feasible to carry a complete replacement rear transmission system with a chain drive but this would be less practical with a shaft. With a shaft there is potentially a lot more to go wrong.

Don't find yourself sitting in the middle of a desert somewhere saying to yourself "chains snapping is not a valid argument here. They just don´t do that under normal circumstances" when you don't have a spare, because in my experience it can happen.

Yeah... I'd never go anywhere without links and a chain breaker.... anything can happen..

Sent from my HUAWEI U8815 using Tapatalk 4 Beta

__________________
Did some trips.
Rode some bikes.
Fix them for a living.
Can't say anymore.

Shit happens, I have more at Home:


I have broken a driveshaft, multiple sprockets, several chains, one output shaft (sprocket cracked) and quite a few chain-followers.

That countershaft sprocket is well past its best, I would replace it before it started looking like that, in fact I usually get 2 sometimes 3 fronts to one rear sprocket before they whole lot is fit for the bin/recycling.

It's good to see that old 'black & white' view of the world in HU where no middle tone or even the slightest tolerance doesn't exist. What I'm amazed of is that comes from people who've presumably been travelling a bit.

I'll try to add my personal humble opinion:

I've replaced my FD bearing on Congo-Angola border with no special tools without any problems.

It looks to me the talk of shaft drive being too complicated and unrepairable is by those who know little or nothing about them or never worked on them on the field outside of the well-equipped garage. Posting catastrophe pictures doesn't say much since there are as many if even more horror stories with chains, whether its grinded output shafts (i.e. common on Africa Twins) or fractured engine casings or damaged swingarms and the list goes on till serious damages to the riders legs or hands or amputations of limbs or even fatal crashes of rear wheel locking up from a broken or poorly adjusted/aligned chain.

I've had chain drived bikes before and still have now. Like all competing systems there's no doubt chain is better in many fields, i.e. short-term extreme offroad rides etc, ultralight performance bikes, it has clear weight and function advantages for certain fields but for me nothing beats shaft drive for simple long distance combined on/offroad overland travel in terms of convenience. I never need to think or fiddle with gearing or carry spare sprockets with me since the factory setting suits me almost perfect. My bike's bottom, rear wheel, sumguard and swingarm are never oily, my pants and boots are always clean of oil drops, I don't have to carry oil or clean/oil the chain afer every long travelling day, I don't have to check the slack, or worry about additional complication of hydraulics when using an automatic chain oiler, my hands are always clean of oil, etc. With shaft drive I just ride. No worries in the weeks of rainy days, or extreme distances of muddy or sandy riding conditions or any other worries. Just ride till it wears the bearing out - just like with your normal wheel bearings. All I carry is spare FD bearing and seal on my travels. I've done a worn FD bearing replacement job 3X on my R1100GS (within 260 000km, some half of this offroad, mostly 2up full luggage covering 6-continents or 80 countries) and by now I can almost predict when it goes and it takes me some couple of hours to replace it with no special tools needed. The FD+seal set costs less, takes less room and weights less than a chain+sprocket set. So living with those pros/cons for me the shaft-drive's a no brainer for long distance overland travel. While I'd prefer chain for some other settings no chain setup replaces shaft-drive for serious long distance overlanding for me, especially now when I know how to field-repair mine when that very rare bad day comes.


IMHO the big downside of the shaft drive is that this fine system is mostly installed only on mammoth-sized bikes today. There're no limits putting this system on smaller bikes, i.e. there are already proven shaft-driven bicycles that can be ridden offroad and I know the people who've pedalled them rave about them. You could probably build an ultralight GasGas tricker bike with a shaft-drive if you really wanted to... It all comes down on how good they are designed and bult IMHO. It's just few or no manufacturers who would even dare to risk by taking such an engineering and marketing challange in todays poor economic climate.

Unsprung weight difference isn't as big as you'd think since shaft itself can be integrated as a supporting mechanism for the swingarm. If I remember someone once compared a R1200 shaft drive with similar chain drive swingarm weights and the difference was surprisingly small. There's also a lot of playroom with different materials and designs, similar like some chain driven competition bikes use to obtain their light weight (i.e. aluminium or even titanium bits, or even a complete carbon-fibre swinarm etc), so it'd be ignorant to stamp shaft drive as some excessivly heavy system with a lot of unsprung weight - when done right - it's not IMO. While it probably won't be good for high-end racing it'd deffo meet most of the demands an offroading enthusiast or an overlander would require.

Personally I think it would be fantastic to have 450-600cc class capable offroad-biased DS bike with a rock-solidly designed and built, field-repairable shaft-drive system that can be used for offroad oriented long distance overland. In fact it'd be a niche market. Understressed torquey long stroke with an air/oil cooled balanced single engine with big oil reserve giving it long engine service intervals - it'd be my dream solo-overlander bike. If 1200cc HP2 managed to get down to 175kg then a 450-600cc class bike would sure get down to 130-145kg range when using decent bits and components. Yes, it'd be fairly more expensive and maybe some 2-3kg heavier than a similar chain driven bike, but if the price is right I'd get it over similar chain driven bike any time of the day. While it isn't perfect, a proper shaft drive just feels, performs and does right for what I do. IMHO design-wise it's elegant in comparison with the usual "dirty-fiddly" multi-link chain drive system. But who knows, maybe I'm just another idiot who doesn't understand anything about adventure travelling.

Just my humble 2c,
Margus

If only the bearings were all that self destructed on shafts...

__________________
Did some trips.
Rode some bikes.
Fix them for a living.
Can't say anymore.

hi I can remember back when bmw were hinting of bringing out a baby single cylinder gs ,I have always liked the first gs the bmw r80g/s from 1980 and the thoughts of a smaller more fuel efficient but still simple bike had me thinking of moving away from yamahas ,my dream of a 600ish cc single cylinder air cooled engine with shaft drive were dashed when they brought out the funduro they had the chance to do what no other bike maker were doing, just like they had done with the r80 g/s but instead offered just the same as all the rest, a liquid cooled single with chain drive, the rotax engine was a great engine but if bmw had designed their own im sure shaft drive could have been done, a wasted opportunity it seems to me you can only have shaft on big bikes or little scooters yamaha qt50 remember them thanks steve

I've got a 1981 R65 with about 300,000kms on the dial, never had a shaft drive problem. About 100,000 would have been on dirt roads, it always got a wash down as soon as possible after a trip - what else are pillions for?

Shaft drive, along with clutch centre failures are nearly always a rider/driver technique problem on any vehicle - ducks for cover - I know there can be batch problems once in awhile but those are quickly identified and often the problem is changed out at a routine service without the owner knowing. The less honest dealers will charge an owner if the bike is out of warranty (even though its a safety bulletin), getting paid by the manufacturer AND the owner.

The consumer demand for lighter shaft drive bikes, with greater carrying capacity will always mean that the manufacturers are pushing the limits - especially since the demise of old air cooled R series bikes.

Chain drives are a pain if you ask me, dirty, if you are carrying luggage that gets a fine film of oil as well, WHEN they fail it can be catastropic with the chain wrapping around the rear sprocket and locking up the wheel. The engine case can also get smashed with a failure or the front sprocket gets jammed and bang goes the gearbox along with it. I've seen other peripherals get smashed to bits as well - rear lights, indicators, pannier racks, battery, all making the bike hard to use if you are touring.

Yeah, but for this particular model it's the main bearing, rarely the other side's small cone bearing, that I also carry, but never needed. I've met an american guy, an ex-BMW mechanic travelling in Chile with the same R1100GS with 720 000 kilometers on the clock - all stock - pistons, even rings, bores etc etc. Aside from consumables the only things he replaced during this time are a set of gearbox bearings and some 5X that same FD bearing. He also did his last FD bearing replacement in a hotel room in Colombia. He taught me this utterly simple FD field repair trick on R11XX models.

PS: I'm no hero by any means - I'm convinced this job can be done by anyone who can use simple tools. You don't need to be mechanic to do FD bearing swap, just use simple heat expansion (your cooking stove or hot exhaust) to aid removing the old and installing the new bearing. A new seal you can fit with your own fingers. Everything else is just loosening or tightening the simple FD casing bolts. Utterly simple in fact.



The same thoughts with me, it's pity there's no real middle-class DS bike with a proper shaftie. I'm pretty sure with a good marketing it'd be a successful project since it'd instantly fill a huge black hole in the market.

QT50 - yep:



The more I look at it the more I like it this could be a very nice RTW-scooter project - much more original than a Cub at least. That particular shaft looks so robust it could probably take on some 125-250cc engine without any problems.


Looking how small and neat they are on bicycles I think the usability of the shaft drive is endless when you do the design and engineering right:


This bicycle is from the year 1899 (yes).



Good ol' monolevers and the ones before them. But look how minimal and lightweight they were. Also look the 80s BMW Dakar racing bikes - those hand-bult two-sided swingarms look rediculously small and lightweight while they claimed they were more or less the only manufacturer finishing the whole Dakar race with just a single engine and drivetrain. So it's the design IMO.




That's the Dakar winning bike.







Just look how lightweight the other side of the swingarm is. And the guy jumps with what - around 200kg of a bike.






Shaft-drive side is also minimal (the black bit is the exhaust-pipe) considering how much power and abuse it gets. These days you can elliminate that old fashioned drum brake and you already save a lot of weight.

Would be interesting to know how they'd compare weight-wise to HPN designed R900RR single-sided systems used in the Dakar races some 20 years later:










Going lightweight doesn't mean youre pushing something - it's about thinking smarter - using modern engineering and materials available. It's nothing new, it's been going on for ages in tuning companies who just combine the latests engineering knowledge/machinery with the latest materials for competition bikes and earn their dosh with this. BMW uses rather cheapo cast-type material on the new production R-series swingarms, while it's relatively lightweight it isn't particulary über-strong. I'm sure with a premium price range bike, such as the R-series boxers are, they could fit a lot higher end materials for the same bill and still earn profit. But I guess like most, they're just another very profit greedy company and in result the R-boxers don't look so "premium" bikes when you inspect the materials and bits used up close. Owning a brand new BMW-badged bike is so fashionable these days that noone really complains and the sales are still high even during the poor ecomonic times. If their clients would make some serious dissatisfaction noise they'd be forced to adjust, from their salesman rip-off policy back to good ol' German efficency policy. Not going to happen.

I think hope for such an innovation is on struggling companies who'd bite the bullet and make that bold move that'll either bankrupt them or push them high into sales success heavens.

All IMHO of course,
Margus