Trials
Well-known member
Did you keep it long enough to need the extended warranty?
What did it cover for you that makes it worth while?
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Is BMW killing it's famed shaft drive?
- Thread starter Chris-CJ
- Start date
What did it cover for you that makes it worth while?
Trials
Well-known member
You are going to love cassette transmissions.
Trials
Well-known member
that is illogical, if you come up with that forever drive chain, no reason you could not have both.
It's not illogical. You touted the cost advantage of a fixed rear axle. You can't adjust your final drive with one. Not in 30 minutes with a $45 counter shaft sprocket, anyway. Your solution is a second (or third) big $$$ gearbox cassette. That is illogical for the average consumer.
Trials
Well-known member
It was 2 separate posts in regards to 2 separate situations, you combined them into a way the outcome conflicted, not me
If you have this expensive never needs to be adjusted chain, how are you going to accommodate changing the sprockets? Now you need to change the chain length! Do you want to mess with an expensive chain or an expensive gear cluster, you could likely do both if you really wanted to.
With the current tech, unless you're doing a radical gearing change, you just swap sprockets and adjust the axle. Worst case scenario, you have to buy a second longer/shorter chain. Your fixed axle suggestion removes any chance of being able to do that whatsoever. Even with buying a second chain, your chances of hitting the same magic ratio for the fixed countershaft to axle length are so close to zero it's effectively zero, so you can't do it. That leaves only purchasing a second gearbox cassette. How much would that be? A quick look at the microfiche of my transmission and the cost of the shafts/gears/bearings is over $1200. Put all those parts into a quick change cassette assembly and sell it over the counter? At least $2K. Probably more.
Chris-CJ
Well-known member
Off topic and I do not mean to hijack the thread, but it is in the current string of posts, which is "Found out today that the engine for the 850GSA is made in China..."
I have heard that the BMW 310 is made in the TVS factory in India, Triumph components or models are made in Thailand, it is all part of the global SCM.
(The iPhone and most laptops are made in China, certain Buick models are also made in China and people still buy these and use them)
IMO what matters in the end is the standard of Quality Control and the price to which these are built.
I have heard that the BMW 310 is made in the TVS factory in India, Triumph components or models are made in Thailand, it is all part of the global SCM.
(The iPhone and most laptops are made in China, certain Buick models are also made in China and people still buy these and use them)
IMO what matters in the end is the standard of Quality Control and the price to which these are built.
Trials
Well-known member
"With the current tech, unless you're doing a radical gearing change, you just swap sprockets and adjust the axle."
you are preaching to the choir and that's not current tech that is ancient technology.
If you doubt BMW can save money by making a motorcycle with far fewer parts :/ ok, if you say so.
If they introduce a bike with a forever drive chain, why would they build a slack adjuster on it, I don't see that as a "suggestion"as a manufacturer it would become an obvious cost saving design change to pursue.
You know, they could also still design a change the size of the gears in the rear hub too. There is your third option that I never made.
you are preaching to the choir and that's not current tech that is ancient technology.
If you doubt BMW can save money by making a motorcycle with far fewer parts :/ ok, if you say so.
If they introduce a bike with a forever drive chain, why would they build a slack adjuster on it, I don't see that as a "suggestion"as a manufacturer it would become an obvious cost saving design change to pursue.
You know, they could also still design a change the size of the gears in the rear hub too. There is your third option that I never made.
I think innovation it great and I have no idea if this will be good or not.
I still think chains get dirty and many don’t maintain them well and as been mentioned, the sprockets will still need replaced etc. .
However any solution that improves the current application, I’m all for it.
Don’t think it will replace shaft drive for all models but, I can see it for some.
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I still think chains get dirty and many don’t maintain them well and as been mentioned, the sprockets will still need replaced etc. .
However any solution that improves the current application, I’m all for it.
Don’t think it will replace shaft drive for all models but, I can see it for some.
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Apple is going to start manufacturing their budget models (SE?) in India. AFAIK the GM cars manufactured in China are sold domestically only, not exported.
Not with a fixed countershaft to axle length. Swapping up and down with countershaft and rear sprocket sizes you're dealing with circumference changes and a fixed value (chain pitch). It very rarely works out to being equal. Something has to change.
I tried to find a nice expensive cassette transmission for my bike with different ratios,
but all I could find is cheap used ones (between 150 to 300$ US)
Find a price on a used cassette for a BMW S1000R with a different ratio. I'll wait.
Trials
Well-known member
@FullMotoJacket Eat breakfast, drink coffee and go riding, it will all become clear to you very quickly.
That's my plan for today
That's my plan for today
Chris-CJ
Well-known member
Here is a "fly in the ointment" ... with the "never adjust, never lube" diamond coated chain, what happens to sprocket wear?
Chains and sprockets work in tandem, so if there is an everlasting chain, it should sit on everlasting sprockets, no?
I will stay with my flat twin and it's shaft final drive!
Chains and sprockets work in tandem, so if there is an everlasting chain, it should sit on everlasting sprockets, no?
I will stay with my flat twin and it's shaft final drive!
@FullMotoJacket Eat breakfast, drink coffee and go riding, it will all become clear to you very quickly.
That's my plan for today
It's perfectly clear to me. I've built a few single speed mountain bikes and know what's involved with the math of finding a gear ratio that's somewhere close to what you want working with a fixed axle to bottom bracket length and end up with a chain that isn't too tight or too sloppy . And that's with the advantage of having half links available for the chain.
sid_for_speed
Well-known member
no such thing... pure mumbo jumbo!
Curious the picture of the BMW chain linked above that never needs adjustment has all kinds of axle adjustment
Arrrgh. How to say the following without risk of name-calling.
The swingarm on any production motorcycle is welded up of some combination of stampings and extrusions and castings with some simple machined parts involving where the swingarm pivot bearings and suspension linkage have to attach. Regarding the distance between swingarm pivot and axle center-line, it is not held to CNC-machining accuracy, it is production-welding-fixture-and-clamps accuracy.
Likewise ... the engine mounts (which is where the other sprocket is attached). You are not dealing with machined datum surfaces. You are dealing with clearance holes in the chassis for the engine mount bolts. They intentionally have a little bit of wiggle room in them to facilitate assembly.
All this means ... is that with conventional manufacturing methods, the dimension between the transmission output shaft and the rear axle center-line is not held to CNC-machining dimensions, it is held to production-welding-fixture dimensions - probably give or take a millimetre or two when you account for all the tolerance stack-ups.
"Could" you make those parts with machined datum surfaces to achieve CNC-machined accuracy so as to not need any means of adjustment? Sure, but it would cost more than providing a slotted hole and jack-screw for the axle (conventional axle adjustment) by a long shot. And it would screw up people who want to change the final drive ratio.
Doing it the way they've done it, with conventional chain sizing and installation methods, means they change NOTHING in the bike other than the chain (and perhaps the sprockets), it goes down the same assembly line it always did, it also means this new chain technology is retrofittable to any other bike (even a non-BMW bike!) that uses the same size chain (525 - which is a very common OEM chain size).
Couple other things to keep in mind ...
Timing belts also aren't subject to wear in the form of the tooth pitch changing with time. And yet ... Every engine with a timing belt has a tensioner on it as part of the assembly - and those parts (cylinder block, cylinder head) ARE built with CNC-machining accuracy with respect to the center distance between the crankshaft centerline and the camshaft centerline.
Timing chains nowadays in similar applications also have tensioners on them, and those chains operate in continuous oil-bath lubrication. YES, I know the old Chevy V8 didn't have a tensioner on the very short chain between the crankshaft and camshaft ... and those chains went sloppy and caused problems because of that.
Chains need tension adjustment means, whether manual or automatic adjustment as the case may be. Period.
Hack
Well-known member
No one buys a BMW motorcycle so they can show off their "made in China" label.
Yes, lots of stuff we buy is made in the PRC, but we do so fully aware of the fact and for things like phones and computers... Who cares?
BMW... or as my German father would say ...
Beh.M.Vey... has a branding that isn't as far as I've seen advertising...
BMW Motorrad... Proudly built in China.
It may be irrational, but... I've scratched the 850 off my short list.
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