-
Welcome, Guest! We hope you enjoy the excellent technical knowledge, event information and discussions that the BMW MOA forum provides. Some forum content will be hidden from you if you remain logged out. If you want to view all content, please click the 'Log in' button above and enter your BMW MOA username and password. If you are not an MOA member, why not take the time to join the club, so you can enjoy posting on the forum, the BMW Owners News magazine, and all of the discounts and benefits the BMW MOA offers?
-
Beginning April 1st, and running through April 30th, there is a new 2024 BMW MOA Election discussion area within The Club section of the forum. Within this forum area is also a sticky post that provides the ground rules for participating in the Election forum area. Also, the candidates statements are provided. Please read before joining the conversation, because the rules are very specific to maintain civility.
The Election forum is here: Election Forum
2020 R1250rt
- Thread starter jimbem
- Start date
alancoles
Dress for fall & avoid it
Welcome, Grumpy and congrats on the new bike.
Euro-4 hit the RT in 2017 (2016 was for "new" bike models) and Euro-5 will hit it in 2021 (2020 for new models) This might be why BMW brought the 1250 out so quickly to have it on the market for a full 2-years of fine-tuning before needing to satisfy Euro-5. So that takes us to 2021 and beyond. Not sure when Euro-6 will actuially be required for motorcycles.
BMW have several things that they haven't yet done to the 1250 that will reduce emissions:
Variable Valve Timing on the exhaust side - current 1250 is VVT on intake only. BMW did the intake only because it:
I would agree. There are so many identical parts between the two bikes (aside from bodywork) that there must be very little additional cost to BMW to offer the RT while realizing a good bump in sales. Win-Win and another reason why I don't think the RT is in jeapordy.
My feeling is that it isn't a problem for at least another 5+ years when Euro-6 regs come into effect for motorcycles, and they have several tech bits that can help.
Euro-4 hit the RT in 2017 (2016 was for "new" bike models) and Euro-5 will hit it in 2021 (2020 for new models) This might be why BMW brought the 1250 out so quickly to have it on the market for a full 2-years of fine-tuning before needing to satisfy Euro-5. So that takes us to 2021 and beyond. Not sure when Euro-6 will actuially be required for motorcycles.
BMW have several things that they haven't yet done to the 1250 that will reduce emissions:
Variable Valve Timing on the exhaust side - current 1250 is VVT on intake only. BMW did the intake only because it:
- gives the most bang for the buck
- easier
- less expensive
- VVT on exhaust is mostly about reducing emissions, while VVT on intake reduces emissions while increasing HP & TQ
- Using both Port and Direct injection for better power, economy and emissions - https://www.caranddriver.com/news/a15342328/explained-why-some-engines-have-both-port-and-direct-injection/
- many car companies are using this now with good success. I have a 2019 Mustang Bullitt that has 480 HP from 5.0L and yet gets 30 mpg-us on the highway
alegerlotz
Member
GS Bikes are definitely popular. But there are people with no interest in riding one (at least as their primary bike). I don't like sitting up that high, and I like the creature comforts of the RT over a bike like that. I might get a used one for the occasional rides where its additional off road capabilities are required, but as a primary bike, no way.
In terms of being an alternative to the K1600, the differences are huge. The weight factor alone is enough to many to write off the K bike straight away. Also, I can't see many law enforcement agencies coughing up the extra money to purchase a K1600 police bike. The R12XX is a good offering in the law enforcement space.
I'm curious as to what it is about the Boxer Engine that makes it harder to keep up with emissions standards. The tolerances are now nice and tight thanks to liquid cooling. Internal combustion engines comes in many forms, but in the end they are all: air/fuel in - explosion - exhaust out. Is it the maximum reasonable CC size the aspect that you mean?
R bikes and the boxer engines have been rumoured to be "on the way out" since the first K bikes were introduced in the mid 80s. At this rate of demise, the 2050 R####RT should be a hell of a bike.
grumpysquatch
New member
I was thinking about cars when I wrote that, and motorcycles may be less affected, but once the main combustion issues have been worked out, minimizing CO2 emissions becomes a matter of reducing vehicle weight to increase efficiency. And because of the opposing cylinders, boxers are inherently heavier and more complex per unit of displacement than V engines. Porche overcomes this penalty by using light but expensive alloys. At some point though, reducing the weight of the boxer becomes cost prohibitive. The need to go from airhead to oilhead to the wethead indicates to me that BMW is pushing the power limits of the current configuration and is likely nearing the end of what can be wrung from the boxer design. At some point if emissions become tough enough, they won't be able to reduce weight without changing the engine design. Perhaps the RT is in a price class that will tolerate more expensive alloys. I'm not sure.
alancoles
Dress for fall & avoid it
Grumpy, the RT is always reviewed as being one of the lightest bikes in its class. When you compare the weight of any other 125 HP (Wethead) to 135 HP (Shift Cam) bike with full luggage, racks, etc., etc., the weight is very good for how versatile the bike is.
You're quite right that once you have exhausted all other options, reducing weight is the only avenue left, but that presupposes the current Boxer engine is there, and I've not seen anything to indicate that it is.
BMW has just started to use VVT on the intake (don't need it on the exhaust yet), and asymmetrical valve actuation leaving plenty on the table to employ as needed. The 136-HP from the 1254cc of the new Boxer is just a 20% bump (displacement adjusted) over the 2004 Boxer Cup Replica's 1085cc 98-HP, and the new bike gets better fuel economy with lower emissions. Over a decade ago Volvo started putting fibre-optic wiring in their cars. Not to increase bandwidth itself, or to increase transmission speed (both of which it does), but to reduce weight for better fuel economy and lower emissions. The need to meet emission standards and still have significant power and fuel economy has been met quite well with the R1250 engine, for now. After they have employed VVT on the exhaust, dual fuel injectors, etc., and a newer round of emission standards are introduced, if we are not seeing any improvements in either fuel economy or power along with meeting the new standards, then you can figure that they have reached the impass point. Until then, enjoy the ride. ;-)
You're quite right that once you have exhausted all other options, reducing weight is the only avenue left, but that presupposes the current Boxer engine is there, and I've not seen anything to indicate that it is.
BMW has just started to use VVT on the intake (don't need it on the exhaust yet), and asymmetrical valve actuation leaving plenty on the table to employ as needed. The 136-HP from the 1254cc of the new Boxer is just a 20% bump (displacement adjusted) over the 2004 Boxer Cup Replica's 1085cc 98-HP, and the new bike gets better fuel economy with lower emissions. Over a decade ago Volvo started putting fibre-optic wiring in their cars. Not to increase bandwidth itself, or to increase transmission speed (both of which it does), but to reduce weight for better fuel economy and lower emissions. The need to meet emission standards and still have significant power and fuel economy has been met quite well with the R1250 engine, for now. After they have employed VVT on the exhaust, dual fuel injectors, etc., and a newer round of emission standards are introduced, if we are not seeing any improvements in either fuel economy or power along with meeting the new standards, then you can figure that they have reached the impass point. Until then, enjoy the ride. ;-)
lkchris
Active member
Ridiculous.
BMW previously attempted to replace the boxer twin and that didn't work. They'll not make the same mistake twice.
That attempt was, however, serendipitous in that it created the GS phenomenon, as since "touring" boxers became unavailable, the choice was between K-bikes and GSs. GS quickly became BMW's best selling model and remains so. In fact, in the UK the GS is the best selling motorcycle period.
So many people make comments about the RT forgetting the most important thing ... the first priority for the RT is to be a police bike.
*******
And AOC will be President. BAAA!
pglaves
#13338
Parts of this thread sound like what must have been said in the stables at the turn of the 20th century as internal combustion engines were beginning to be used for transportation. I'm positive many a hired hand mucking out the stalls was just as knowing about the future of transportation as many folks are now as they make fun of evolving technologies. At 74 I may not be around to see the full blown electric revolution but some on this Forum will be and will be amazed at what they scoffed at.
My Lithium ion booster battery is about 1/3 the size of a 6v lantern battery and will crank a V8 engine with ease. And that isn't even cutting edge technology.
My Lithium ion booster battery is about 1/3 the size of a 6v lantern battery and will crank a V8 engine with ease. And that isn't even cutting edge technology.
