Knut you bring always up pumping losses on a boxer but look on jootube as there a guys getting up to 11500 ! RPM out of Porsche boxers and the new GS is doing peak power at 7750 rpm…it shuts off at 9000 rpm…Plenty potential left and with a center bearing there would be even potential for more for a S and M-GS or XR version however they want to call it…But as it is plenty good except for the shorter stroke but as I said they are probably holding back for future R1350 and R1400 updates following in 4 year product update cycles…
$31000 Wankpanzer !
- Thread starter Arsey
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3 mm stroke as in 50 cc at a time doled out in homeopathic doses this is why BMW probably decreased the stroke from 76 to 73 mm make some money by giving us another 10 hp and a few little other updates every 4 years…
You are missing one vital point.
I'm not saying it's a boxer issue, I'm saying it's a Boxer TWIN issue. As soon as the boxer gets more than two cylinders, you will have pistions that moves simultaniously in and out, hence canceling or at least reducing the pumping action...
As for a center bearing for the crankshaft: It may perhaps strenghten the crankshaft.
But it will increase the longitudinal distance between the cylinders.
Some of the vibration from the twin boxer is caused by the offset of the pistions. Increasing the offset will enhance the vibration.
But, a bit of hypotetical thinking:
Is it possible that engineers that are capable of designing the twin boxer to the performance level that it now has also have considered the center bearing and stayed away from it for a reason?
There may perhaps be a tiny possibility that they are not completely morons
Troppo
Bemused observer
WTF would BMW engineers know?
Knut the R18 has a mittellager/center bearing...Only drawback I see is more costly to produce but more high rev as also crank case in case of heavy R18 pistons , Stability with the slight visual disadvantage of cylinders that might be a inch offset...Small price to pay !
Not much obviously ; foot brake that operate front brakes...Missing center crank bearing that let the boxer only do 9000 rpm...Starter Solenoids that shorten out...Tanks that only last for 150 miles...Taillights that might confuse drivers of cages...The list is long...LOL
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Knut you know why they did it...Without it the engine cases/crankshaft would not have made it to the first oil change at 600 miles because the pistons are so big and heavy...A Mittellager R1300-R1400 could do 10000 rpm all day long and still make gobs of torque with no problem of crank flexing or destruction of the engine cases...Oh well with the M1300GS going off-road and no new sportboxer on the horizont no need for this...Boring ! I am glad I experienced 2 R1100S bikes and Boxercup which very fun times ! Flasch also said the obvious that the R18 is not a hit (who would have thought LOL) and that the will put that motor in a real BMW soon...What Yamaha did with the MT-01 could work for BMW with the R18 done right...Or a R180/8...as the new XL version of the R100/7...LOLWell, it certainly helped the RPM. Redline 5 750 RPM.....
Increase in stroke brings about an increase in the piston mean and max velocities which rams up the acceleration and deceleration of the pistons, leading to snapped conrods etc.
Read something about it when Yamaha claimed 17k rpm for the original R6 (and that had wee little pistons...)
Question for Janitor, can the reaction score venture into 4 figures.....?
Read something about it when Yamaha claimed 17k rpm for the original R6 (and that had wee little pistons...)
Question for Janitor, can the reaction score venture into 4 figures.....?
If BMW would have left the stroke alone instead of decreasing it by 3mm compared to the 1250 the new 1300 would have been a 1350 and probably felt faster than the 1250 below 80 mph despite having taller gearing And the piston speed would have been the SAME ! Btw 911 GT3s have 81 mm stroke and do 9000 rpm all day long...The 1300 has only 73 mm stroke by comparison !
And he makes some good points about the rubbish switch gear from 55 mins in…..
Yes, really the cumbersome nature of controlling / switching the myriad of functions through the same two buttons and display. I'm not sure what else they can do? They can't have a separate control for every function but things like heated grips and seats could have their own buttons on the end of the bars and side of the seats. And they certainly should be back lit.
Troppo
Bemused observer
Do you have a comprehension problem?
I told you before that I could easily do feet up U turns on the 1300 I rode by dragging the rear brake....the front didn't fold.
You haven't ridden a 1300 - I have. Your opinion is therefore worthless.
Do us all a favour, and go away.
Good luck with the go away bit , he just keeps throwing up the same puke in a never emptying bucket .
You do get used to it , and once you set the buttons it’s easy and not as bad as all make out . Ownership helps as it is confusing first time on a test , but I remember similar when I first had the function options on the gs. The new one works well for me . As for back lit , nice but not essential as I know where my buttons are lol
Troppo
Bemused observer
Ridden one, have you?
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