So not even true variable valve technology, just two ratios. I’m not that imprsssed, a tad disappointed even.
1250 Video
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fred_jb
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Of course, there may be changes in the engine management designed to lock out Hilltop type mods!
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Especially when the moving pin system wears and jams..... lol
Had my 1200S multistrada wheels painted high gloss gold back in the day...they looked awesome with the Ducati red paint. Think it depends on the bike.
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They can try! But they'll need Geoff to make the test bikes run right for the press.
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Nice evolutionary update to keep the GS on top of the sales charts for the next 4 years when the all new GS with carbon-frame will the the light of day in 2023...
BMW's use of the VW/Audi type cam-phasing system should mean reliability from day one which is way less complex than the true variable cam lift & timing system seen on the alpha-Technik GS.
143 NM TORQUE is huge and will mean that KTM and Ducati pilots will only see the GS tail on country roads...
136 hp is a little low but more top end power and more than 140 mph top-speed probably would mean high speed stability issues for the GS...I rather keep the quicker steering geometry and give up 15 mph on top.But acceleration and roll-on should be much stronger with the same gearing but 18 NM more torque !
As also it means there is another 1250 rpm ceiling for a more powerful "R1250S"...
Can't wait to take it for a test-ride come october/november !
Hopefully the R1250GS-XR with 17 inch wheels is still in the works for 2020...
With 150hp/140 NM of course...
Nice update...
Only the quieter exhaust sucks but I'm sure Akrapovic already has a solution...
BMW's use of the VW/Audi type cam-phasing system should mean reliability from day one which is way less complex than the true variable cam lift & timing system seen on the alpha-Technik GS.
143 NM TORQUE is huge and will mean that KTM and Ducati pilots will only see the GS tail on country roads...
136 hp is a little low but more top end power and more than 140 mph top-speed probably would mean high speed stability issues for the GS...I rather keep the quicker steering geometry and give up 15 mph on top.But acceleration and roll-on should be much stronger with the same gearing but 18 NM more torque !
As also it means there is another 1250 rpm ceiling for a more powerful "R1250S"...
Can't wait to take it for a test-ride come october/november !
Hopefully the R1250GS-XR with 17 inch wheels is still in the works for 2020...
With 150hp/140 NM of course...
Nice update...
Only the quieter exhaust sucks but I'm sure Akrapovic already has a solution...
fred_jb
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I agree - it think it is a very limited system, so probably just a stopgap pending something more ambitious in future.
It also seems a little different to some other systems. Effectively it has two different inlet cam profiles, one for part load running and one for full load running, and the engine management will move the camshaft laterally to switch between the two, but it only operates on the inlet valves so can't provide complementary changes to the operation of the exhaust valves. It is also a sudden switchover and not a gradual change so the cam profiles can't be optimised across the rev range.
In other systems, like Ducati's and Suzuki's, I believe that there is only one cam profile, but the angular position of the cams can be altered with respect to the crankshaft in order to change valve timing and overlap, and this change can be gradual and engine speed dependent to optimise operation throughout the rev range. These systems also seem to be able to operate on both inlet and exhaust to provide complementary changes.
With the BMW system the mechanical changeover between the two cam profiles will be sudden, which could make it very noticeable. Having experienced Honda's VTEC transition going from relatively gutless to manic at 6500 rpm, I would not want anything like that, but as the BMW system is load and not rev dependent maybe it won't be so noticeable. I guess it will depend a lot on the timing of the change and what other changes to fuelling and ignition timing are made to mask the sudden transition.
The other concern I have is the mechanical wear and stresses that could be introduced as the camshaft moves, but I am assuming that it is possible to complete the move quickly enough for it to take place during a period when both inlet valves are closed and where there is therefore no difference between the profiles of the low and high load cams to obstruct movement across the cam followers. I could imagine some very expensive noises ensuing if this lateral movement becomes mistimed!
Fred
Nothing will be mistimed as they can only slide over while the cam lobes are flat.Try a VW GTI and you will see it is totally seemless.Of course we will know for sure after the first test-rides.
As for added complexity I can only see the unit that chooses the low rpm/high rpm pin to choose the fat torque/high rpm power cam lobe !
As for the Ducati or Kawasaki single cam lobe systems or the mechanical system on the GSXR 1000 those systems doen't work as good as 2 cam lobes ground for either fat torque or high lift high hp applications as it only advances or retards the same cam profile.
And the Honda VTEC system on the VFR800 worked totally different with a hydraulic pin that went from 2 to 4 valve operation to lock in the rocker which neither gave good low rpm torque or high rpm hp and felt like the engine had hiccups around 6500 rpm.And was expensive to maintain come valve adjustment time...The BMW system has 2 cam lobes optimized for torque and power and probably changes around 5500 rpm looking at the cams and will be adjusted as the current one...maybe the intake cam can even stay and you can push the rockers sideways to change the little half ball bearing shims which would make it even easier.In a few days we will know for sure but I like what I see !
The alpha-Technik VV-L system was mechanically beautiful but probably too costly and complex for mass production and long mileage use and maintenance...
As for added complexity I can only see the unit that chooses the low rpm/high rpm pin to choose the fat torque/high rpm power cam lobe !
As for the Ducati or Kawasaki single cam lobe systems or the mechanical system on the GSXR 1000 those systems doen't work as good as 2 cam lobes ground for either fat torque or high lift high hp applications as it only advances or retards the same cam profile.
And the Honda VTEC system on the VFR800 worked totally different with a hydraulic pin that went from 2 to 4 valve operation to lock in the rocker which neither gave good low rpm torque or high rpm hp and felt like the engine had hiccups around 6500 rpm.And was expensive to maintain come valve adjustment time...The BMW system has 2 cam lobes optimized for torque and power and probably changes around 5500 rpm looking at the cams and will be adjusted as the current one...maybe the intake cam can even stay and you can push the rockers sideways to change the little half ball bearing shims which would make it even easier.In a few days we will know for sure but I like what I see !
The alpha-Technik VV-L system was mechanically beautiful but probably too costly and complex for mass production and long mileage use and maintenance...
fred_jb
Registered user
I agree that the single cam profile rotating camshaft systems are limited because they can only change valve timing and not valve lift, but the BMW system is also limited. It can only provide one cam profile optimised for high power and one for low power. It doesn't have any way to optimise the cam profile for a range of conditions, just a binary choice. Something like Fiat's Twinair/MultiAir system provides much more variability across a wider range of operating modes. The 900cc twin cyclinder engine in my wife's Fiat 500 is a real hoot, though lack of variation in torque with revs means you don't get the usual cues to change up a gear until you hit the rev limiter!
143 NM, baby.....YEAH....
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I actually find these threads amusing, most are screaming yeah baby more power faster, yet 99.9% of riders who buy a GS buy it because it is easy to ride comfortable on the older bones, and can go on the gravel if needed, it is very similar to the computer threads, new computer coming out more speed more power, must have,yet most only send email surf the net, and look at the odd video..........
I personally could not take my GS to its speed limit or cornering limit, so no more speed or power needed, and 2 up it pulls like a train, well impressed. 
I personally could not take my GS to its speed limit or cornering limit, so no more speed or power needed, and 2 up it pulls like a train, well impressed. I belong to the group that said, wtf. only two levels?
But, come to think about it, until proven wrong, it seems like a good compromise. 143 NM from a 1250cc, it can not be all bad.
BMW started with the VANOS (like in Ducati) in the -90's in their cars, and Valvtronic was launched shortly after the turn of the century, so they are familiar with the technology.
A full functioning Valvtronic would be nice, but complex an bulky. The engine is wide enough as it is.
The two-lobe system is new to BMW, but has been used for quite a while by VW/Porsche, and there has not been heavy issues about reliability nor jerky switchover. The actuator pins may appear to be a vulnerable item. But probably, these electronically controlled actuators might be made by the same supplier that makes the for VW/Porsche, so I don't worry too much (last famous words).
At the end, the proof is in the pudding. Can't wait the try it out.
But, come to think about it, until proven wrong, it seems like a good compromise. 143 NM from a 1250cc, it can not be all bad.
BMW started with the VANOS (like in Ducati) in the -90's in their cars, and Valvtronic was launched shortly after the turn of the century, so they are familiar with the technology.
A full functioning Valvtronic would be nice, but complex an bulky. The engine is wide enough as it is.
The two-lobe system is new to BMW, but has been used for quite a while by VW/Porsche, and there has not been heavy issues about reliability nor jerky switchover. The actuator pins may appear to be a vulnerable item. But probably, these electronically controlled actuators might be made by the same supplier that makes the for VW/Porsche, so I don't worry too much (last famous words
).At the end, the proof is in the pudding. Can't wait the try it out.
I actually find these threads amusing, most are screaming yeah baby more power faster, yet 99.9% of riders who buy a GS buy it because it is easy to ride comfortable on the older bones, and can go on the gravel if needed, it is very similar to the computer threads, new computer coming out more speed more power, must have,yet most only send email surf the net, and look at the odd video..........
You are dead on right.
But old farts in many ways behave like a dog chasing a car. The fun is in chasing it. If the dog ever catches the car, he would not know what to do...
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.... yeah, more tyre wear, more final drive wear, more clutch wear.
In the real world, out riding with your mates, it wont be any faster than a 1200 GSA.
Your cornering speed brain won't change, the weight won't change, tyre grip won't change, you're riding ability wont change, nothing will change....
But you'll be paying for it anyway
Deleted account 191119001
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.... yeah, more tyre wear, more final drive wear, more clutch wear.
In the real world, out riding with your mates, it wont be any faster than a 1200 GSA.
Your cornering speed brain won't change, the weight won't change, tyre grip won't change, you're riding ability wont change, nothing will change....
But you'll be paying for it anyway
Could be life changing though.........
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I actually find these threads amusing, most are screaming yeah baby more power faster, yet 99.9% of riders who buy a GS buy it because it is easy to ride comfortable on the older bones, and can go on the gravel if needed, it is very similar to the computer threads, new computer coming out more speed more power, must have,yet most only send email surf the net, and look at the odd video..........
You beat me to it
I actually find these threads amusing, most are screaming yeah baby more power faster, yet 99.9% of riders who buy a GS buy it because it is easy to ride comfortable on the older bones, and can go on the gravel if needed, it is very similar to the computer threads, new computer coming out more speed more power, must have,yet most only send email surf the net, and look at the odd video..........
Disagree. Two up and luggage my GSA was wanting. Despite Hilltop map and Akra the bike needed more. Especially when you brimmed the 30l tank! I know I'm right
because I have zero issues with the more powerful 1290S. Imagine the new engine will attempt to address the deficit.
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Disagree. Two up and luggage my GSA was wanting. Despite Hilltop map and Akra the bike needed more. Especially when you brimmed the 30l tank! I know I'm right
But that isn't about the bike, that's about the weight on the bike....
Deleted account 191119001
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Disagree. Two up and luggage my GSA was wanting. Despite Hilltop map and Akra the bike needed more. Especially when you brimmed the 30l tank! I know I'm right
So you are in the 0.1% camp Chris, get the money ready.............
Huh?? No....it's definately the bike. As always, if you don't think you need one, don't buy one
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