The Boxer Engine - A Question For the Historians

It's the bloody EU with their meddlesome interference on emissions and the like :blast

Easy target! We would have emission regs forced on us without the EU. We could even have ended up with the US ones. The makers would not produce different versions for every country so at least we get an EU version not the American one.

John
 
Would I be right in thinking that the air / fuel mixture and emissions are controlled by the engine management system so there isn't a simple tweak to adjust? Hence the remap being a popular option.

Regards,

John.
 
It does have perfect primary balance - the 'rocking couple' is not part of the primary balance.

oooops I made an error is does not have perfect primary balance as I thought, the rocking couple is at the fundamental frequency, i.e. one oscillation per revolution - the big masses, pistons and con rods do balance though as they move in opposition, the balance shaft attempts to reduce the rocking couple.
 
Today I'm being a pedant...

Edvard:- no "e" in nous

Steptoe:- no "e" in shiny

Stop wasting vowels, anyone would think they're free!
 
Easy target! We would have emission regs forced on us without the EU. We could even have ended up with the US ones. The makers would not produce different versions for every country so at least we get an EU version not the American one.

John

If I was typing this from my home in the USA and rode a US Spec GS, I would have said it's the meddling US Government what's caused it. However, as I'm typing this from my home in Wiltshire and as both myself and the OP live within the EU one would have to conclude that it's the EU and not the US that's meddling with our bikes :comfort
 
Would I be right in thinking that the air / fuel mixture and emissions are controlled by the engine management system so there isn't a simple tweak to adjust? Hence the remap being a popular option.

Regards,

John.

Yes the air/ fuel is controlled by the engine management system (BMS-K), which is controlled in closed loop by the lambda sensor which takes priority as it measures the exhaust ( output) .
There are devices that try to trick other inputs but the lambda controls the BMS-K to give a 14.7 1 afr in closed loop..
So you offset the lambda with an XIED and fool the BMS-K to fuel at your chosen air fuel ratio.
As it is the control input the BMS-K doesn't know and cant adapt around it.
The bike is in closed loop a lot of the time and the open loop learns by adaptation from the closed loop.
 
If I was typing this from my home in the USA and rode a US Spec GS, I would have said it's the meddling US Government what's caused it. However, as I'm typing this from my home in Wiltshire and as both myself and the OP live within the EU one would have to conclude that it's the EU and not the US that's meddling with our bikes :comfort

I don't dispute that it is the EU that makes European regulations. The point I was making is that someone will. BMW or anyone else for that matter could not afford to make bikes to conform to different regs in different countries. Meeting these demands is expensive enough as it is. Therefore they would make bikes to conform to one standard if there were no international agreement. That standard by default would be the US one. Not a good result I would suggest. Unless you think we should have different standards, one for Wiltshire maybe?, and are prepared to accept the added costs, we have to have an agreed standard. Having one for Europe makes sense. OK we could decide we don't need any standard at all but again this would only work if this was agreed at a multi national level. ie by the EU. Do you think BMW would bring back carbs and points for the UK market if we had no rules? No, they, and us, could not afford to do so.

Leaving aside the politics we are in Europe, we have moved on from the days of the famous headline "Fog in the Channel - Continent Isolated"

John
 
Hi Guys,

I've got a question for the guys who have owned / ridden BMWs for a long time.

I'm going to add the disclaimer that I'm not criticising my own bike, I love it, and the only thing that would replace it is a slightly newer one in the sandrover colour scheme. I'm just interested in how it has developed so no headslapping icons please.

The mechanics of the GS engine seem bullet proof and although the boxer engine is a bit unusual its as simple as any internal combustion engine. Attached to it is what appears to be a convoluted fuelling / engine management system that seems fraught with performance problems. There are hundreds of posts on this site about lean running, booster plugs, remapping, accelerator modules etc. (I've fitted one of the latter.)

Remember this isn't a criticism but I did my DAS on a new Honda CBF 500 which was a pretty dull bike, but it could pull away slowly in first gear with no accelerator and then toodle along forever. As I said there was only ever one bike that I was going to buy and I have got used to the occasional lurch and splutter. So my question is why has the GS developed in this way? I don't want to know how to fix it, I've read all the posts on remaps and bolt ons and the cheapest option has done a very good job for me. I'm just a bit surprised that I would need to fit one. Is there a reason why BMW havevn't addressed the problem?

Having received some very random answers to previous posts I would be really grateful if you could answer the question that I'm asking above and not provide me with an answer that refers me to Google, the IAM, a Youtube video about milking cows, or any answers designed to show how much smarter than me you are.

Cheers.

There isnt anything to fix. Its a characteristic of bike enthusiasts that they like to tinker and modify - you only need to think of the cruiser lot to see this. And in the case of the GS there are quite a lot of riders who have come from sports bikes and want to make a higher powered version of the GS for road use. Their bike and their right to do so, but dont for a moment think they are curing a problem. They arent. In fact in many cases they will be making one. The GS isnt perfect. No bike is. But apart from mods like a better seat, huggers etc, theres nothing much that Joe Public can do to better what loads of engineers and millions of £ have not done at BMW.
 
There isnt anything to fix. Its a characteristic of bike enthusiasts that they like to tinker and modify - you only need to think of the cruiser lot to see this. And in the case of the GS there are quite a lot of riders who have come from sports bikes and want to make a higher powered version of the GS for road use. Their bike and their right to do so, but dont for a moment think they are curing a problem. They arent. In fact in many cases they will be making one. The GS isnt perfect. No bike is. But apart from mods like a better seat, huggers etc, theres nothing much that Joe Public can do to better what loads of engineers and millions of £ have not done at BMW.

Whilst there is an element of truth in what you say I would point out that BMW along with just about everyone else don't necessarily give their all with each new vehicle. Every manufacturer looks at the market and their rivals in these markets. If every bike in that segment has, say,100 bhp then they have little incentive to give much more. They might go to 110 bhp but would need to beware of a rival then going to 120. So I suspect that what happens is that the market gets maybe a 105 bhp version because that is more than enough given the competition. They may have developed versions up to 120bhp but there is no incentive to launch these unless others up the anti

This theory applies to several parts of the bike, there might be for instance, better brakes waiting in the wings should the market dictate a need. They make good bikes these days, and I wish I could afford a new GS, but the manufacturers are not a philanthropic as you imply. I would therefore suggest that improvements on the standard bike are possible. As to such improvements being available or affordable, that is another matter altogether.

John
 
Back in the 1990s I had a VW TDI 90 chipped (remapping in new money). It now made 110 bhp and behaved just like the more costly 110 version. Later more powerful models would also upscale.

This pretty much proved the manufacturer was deliberately under rating their engines to sell the more powerful versions at a premium price.

BMW don't have different boxer engine specs for the GS but this under-rating via engine management does seem to be happening. The Hilltop remapped bikes don't use any more fuel than standard so emissions must be similar. The question is why do BMW feel the need to dial in a lumpy torque curve and under-fuel the engine. Seriously they can't be less capable than Hilltop so why do they do it? No sarcasm intended.
 
Back in the 1990s I had a VW TDI 90 chipped (remapping in new money). It now made 110 bhp and behaved just like the more costly 110 version. Later more powerful models would also upscale.

This pretty much proved the manufacturer was deliberately under rating their engines to sell the more powerful versions at a premium price.

BMW don't have different boxer engine specs for the GS but this under-rating via engine management does seem to be happening. The Hilltop remapped bikes don't use any more fuel than standard so emissions must be similar. The question is why do BMW feel the need to dial in a lumpy torque curve and under-fuel the engine. Seriously they can't be less capable than Hilltop so why do they do it? No sarcasm intended.

Sorry I thought this was well covered. They have to make the bike meet emission standards, to do this the vehicle must pass at some fairly arbitrary points in it's operating range. They set it up to do this and create the problems you mention because they have to. The likes of Hilltop have no such restrictions placed upon them. It is quite possible that out in the real world the remapped bike will be no more polluting than the standard one. Very difficult to prove either way, it would almost certainly fail the official testing procedure (I'm not talking about an MOT type test) but then if the standard bike was tested at different points than those specified it might also fail.

John
 
Back in the 1990s I had a VW TDI 90 chipped (remapping in new money). It now made 110 bhp and behaved just like the more costly 110 version. Later more powerful models would also upscale.

This pretty much proved the manufacturer was deliberately under rating their engines to sell the more powerful versions at a premium price.

BMW don't have different boxer engine specs for the GS but this under-rating via engine management does seem to be happening. The Hilltop remapped bikes don't use any more fuel than standard so emissions must be similar. The question is why do BMW feel the need to dial in a lumpy torque curve and under-fuel the engine. Seriously they can't be less capable than Hilltop so why do they do it? No sarcasm intended.

You're conflating two different issues as even you acknowledge.

The reasons why BMW map the engine as they do has already been detailed previously. It's something every manufacturer does alongside measures to help it comply with noise, chassis and even local mudguard regs.

I come from a background where 'tuning' was primarily a performance enhancing aid and by feck I've improved the performance of a few bikes over the years. In most cases, tho' still perfectly acceptable, I made 'em slightly worse to ride day to day tho' tbh.

I've still got my old Busa and it's got buckets of guts and another 20hp or so over it's already prodigious power output but..........it's a nicer bike to ride on a tour when standard when all's said and done, standard exhausts and original ECU. Not as 'impressive' but nicer.

Along comes the GS and let's face it no tuners were particularly interested in 'improving' them nor (surprisingly) were the riders (at least not in the engine dept) for years.

It's a tremendous sales success story, has brought many new owners into the fold, many of them with a performance oriented tuning bent and then, all of a sudden the bike has a 'problem' and Mama Mia the tuners, with their dwindling sportsbike rider customer base, can sort the 'problem' out for only a few hundred quid on top of the farsans already spent on other add-ons.

It particularly perplexes me that riders without any other frame of reference, apart from the bike they did their test on, perceive the 'problem' to be serious enough to partake in the wizardry that can be performed:nenau

Almost as much as it puzzles me why more experienced riders develop 'Princess and the pea' syndrome, still perceiving the problem with a big, perkily tuned flat twin even after several mattresses have been applied.:confused:

Get on the bloody things and ride. Put a fruity exhaust on and enjoy that too by all means just don't kid yerself you're 'improving' anything at all.
 
It particularly perplexes me that riders without any other frame of reference, apart from the bike they did their test on, perceive the 'problem' to be serious enough to partake in the wizardry that can be performed:nenau

Almost as much as it puzzles me why more experienced riders develop 'Princess and the pea' syndrome, still perceiving the problem with a big, perkily tuned flat twin even after several mattresses have been applied.:confused:

I don't think you have to serve some sort of motorcycling apprenticeship to have an opinion on a bike's performance, or comment on it on this site particularly if you're keen to learn about more than just riding the bike. That does sound just a tiny bit elitist.

I stated very clearly in the original post that I am interested in the GSs development and wasn't identifying a problem. Thankfully most of the responses have been very informative and support my own conclusion that the lean fuelling is a characteristic of the GS that can be improved if you can't live with the occasionally jerky throttle response. I suspect that BMW could have improved this issue at source and that an individual map per location could have been possible but as some contributors have stated riding my bike from the UK to Sicily would require a European standard of emission control.

I did wonder how long it would take for someone to tell me that my opinion isn't relevant, even if I was using the site for it's intended purpose. Shame.
 
I don't think you have to serve some sort of motorcycling apprenticeship to have an opinion on a bike's performance, or comment on it on this site particularly if you're keen to learn about more than just riding the bike. That does sound just a tiny bit elitist.

I stated very clearly in the original post that I am interested in the GSs development and wasn't identifying a problem. Thankfully most of the responses have been very informative and support my own conclusion that the lean fuelling is a characteristic of the GS that can be improved if you can't live with the occasionally jerky throttle response. I suspect that BMW could have improved this issue at source and that an individual map per location could have been possible but as some contributors have stated riding my bike from the UK to Sicily would require a European standard of emission control.

I did wonder how long it would take for someone to tell me that my opinion isn't relevant, even if I was using the site for it's intended purpose. Shame.

Your opinion is, of course, relevant.

I did pose a couple of queries myself as a result and, horror of horrors, expressed my own view.

FWIW I had a crack at some experienced riders too.

You may disagree but don't go fecking looking for a cross yet;)
 


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