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Discussion Starter · #21 · (Edited)
No. I'm 100% serious.

Carburetors are superior to fuel injection. I don't know if it's feasible to put one on a K1200S, which is very unfortunate, because EFI is awful. Carburetors weren't discontinued for reasons of fuel economy, power/performance, cold starts, or even tailpipe emissions.

Carburetors were banned because the fuel from the float bowls evaporates into the atmosphere when the engine sits, and regulators had this gaga fit about gasoline vapors being the worst thing ever in the world.

So much so did they have this fit that it's the same reason again why some states have those ridiculously stupid fuel pumps at gas stations that are a total pain in the ass. The ones where you have to fight to get the thing to pump gas.

It's also same reason why you can't buy a normal fuel canister anymore, but have to get one with some mechanism to stop the fuel vapors escaping (more on this later).*

It's really important to remember that carburetors were NOT discontinued. They were used in production bikes right up until the inevitable EPA ban in 2009 or whenever. They were NOT discontinued for reasons of performance, reliability, efficiency, or, even tailpipe emissions (I think I'm right in saying).

EFI is not an inherently superior technology to carburetors. A carburetor is an analog computer, capable of instantaneous processing AND implementation of information. There has been this very pretty picture painted by the industry that fuel injection is simply a single fuel injector. See here:

Automotive tire Font Audio equipment Bicycle part Auto part


What's wrong with this picture is that in order for a fuel injector to do what a carburetor does, it also requires:
A camshaft position sensor
An Airflow Meter
A fuel pump
A manifold pressure meter or Airflow Sensor
Probably a barometer
And then finally an ECU
Of course you also need the wiring for everything
Also all of these things need to sit in the worst environment you can think of for anything electronic.
Also you need 12v of power or nothing will start.
Oh and it has to handle voltage fluctuations of the worst sort.

But none of this is for actual performance improvements.
 

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Discussion Starter · #22 ·
I thought of some more things EFI needs:
Secondary air injection for when it's cold
Oxygen sensors
Oxygen sensor heaters
preloaded lookup tables
 

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All of those things add up to a more effective and efficient system. The only reason carburettors lasted so long was because they are a much cheaper system than FI - not because they are better in any way. I have heard said that carburettors can produce more power than FI. This MAY be true but it would be at a specific point in the rev range. FI produced more power over the whole of the rev range. Perhaps you should get one of these and end your angst😁
Bicycle Wheel Tire Bicycles--Equipment and supplies Bicycle wheel rim
 

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To each his own.

Personally, all the bikes I have owned except for the current two (K1300S and R1200GS LC) have been carburated. I was quite happy with every carburated bike, and I liked the 'simplicity'. This was the case even though it meant a non-trivial amount of maintenance poor fuel economy and other grief relating to the carbs. This included dealing with winter storage and the risk of having issues in the spring, ethanol gasoline, and other issues. My current bikes are my all-time favorites partly because they are fuel injected. I am happy to move on to fuel-injected bikes for every reason mentioned in this thread.

One downside of 'electronic'/FI bikes, similar to collectable cars, may turn out to be the prospects for long-term ownership and collectability.

I just don't see how it is realistic to think we would have the wonderful K1200 and K1300 engines we all enjoy if they were not fuel injected.
 

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carburetors are great once you get then tuned properly and the engine is up to temp. But once the temperature or altitude or humidity changes all bets are off and don’t forget how cranky they get while warming up from a cold start on cold day. I don’t miss messing with the choke and idle screw. Then there are the dead spots in the rpm range who's severity changes with the weather. Don’t get me wrong, carbu are amazing devices that work way better than they should, but they are not better than fuel injection. oh and unless you plan to replace the alternator and ignition module with a magneto and mechanical points a carbureted engine won’t survive an emp. Now you may prefer carbs over FI, and it is true that FI is more complicated due to the electronics and sensors involved, but all that stuff is what makes FI engines way more user friendly than carburetors.
 

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I think you're onto something - Or on something 🙄 You'd better get onto the Motogp and F1 teams. Oh and NASCAR. You could be onto something that they'd like to know And the US military so while you're there let them know as well.

Are EFI systems better for NASCAR cars?
Despite the high costs involved in switching to and maintaining EFI systems, they have pros that outweigh the cons. NASCAR races have seen far fewer retirements due to fuel injection system failures since they were introduced. Retirements due to engine failures have also come down drastically. That in itself is argument enough to refrain from using carburettor fed engines.
Carburettors could be adjusted by mechanics to suit the cars, drivers and tracks. A carburettor allows the mechanic to make 24 adjustments. EFI systems allow a mechanic/technician to make over 150 adjustments to the systems. Most of the adjustments that have to be made to the system can be made electronically. An EFI system can be optimised to get maximum efficiency and environmentally friendly performance from the engine.


You could just buy one of these
View attachment 30999
But you were really joking weren't you
Hey don’t dis the Jawa! I had a Jawa 175 in 1965 for my first year in college! It was a cool bike and all I could afford for $75. Lasted a lot longer then my $50 Ducati 125 which I’m not sure was even made by Ducati! Then I bought a Ducati 250 Diana and that was pure heaven until you needed the lights! Meanwhile, as a retired master BMW mechanic and EE, I think the carburetor boys must be smoking something really good to think that changes in throttle position and vacuum are as precise as electronically controlled FI... Even the mechanical FI systems like the Kugelfischer system on the BMW 2002TII or early BMW/Mercedes aircraft/car engines dating to 1939 were far better than carbs especially in aeroplanes!
 

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Having experienced a K2 magneto with Amal GP carbs and Lucas electrics on a Norton, excuse me while I vomit at the thought of going back.

You probably will not survive EMP. Nothing is unsheilded electronic is going to work.
 

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Discussion Starter · #30 ·
Eh? I know there is opinion, and I do respect yours, but pretty much the entire automotive/ICE industry would disagree with you. For scientific and emissions reasons.
Please enlighten!!

I disagree with the entire automotive/ICE industry on this.

At the very least for bikes. If they had put even 1/10th the effort/research into carburetors they put into stupid EFI, we would have absolutely incredible carburetors. I don't think there has been a carbureted bike with a catalytic converter. This would solve literally all tailpipe emissions issues. It would not solve the oh-so-scary and pointless gas evaporating issue that is the reason carburetors were even discontinued in the first place (not performance, fuel economy, tailpipe emissions, or anything else, it bears repeating)

See above all the shit that's actually required to get EFI to work, and then look at the myriad of posts on this forum about people having EFI issues; although they don't recognize it as EFI issues. They make posts like "oh this sensor issue, need a booster plug, need an O2 sensor, need power commander, need tune, need PhD in Computer Science to make it work, etc. etc. etc.". Somehow we've made bikes that can't do hot starts, but nobody actually attributes this to a fuel injection problem "oh it's a sensor issue". Pfff.

This isn't in any way better than what carburetors offered except maybe cold starts. I'm pretty sure the late model Japanese bikes that still had carburetors had electronically adjustable carburetors for altitude, The Yamaha YZF600R and Kawasaki ZZR600.

Also NOTHING fuel injected can match that analog throttle response you get from a carburetor. NOTHING. People content with EFI are people content to live in a simulation. Blue pill. With carburetors, you pick up on the tiniest nuances of your engine. You become one. It's 100% a thing, and it's TRAGIC that whole generation of people will never understand just how fantastic carburetors are because they have swallowed the fuel injection propaganda. What's even more tragic, the throttle response could be even better, but the EPA nixxed that on carbs because they hate happiness. My friend's jet ski has little dump valves that pour gasoline directly into the intake whenever you squeeze the throttle quickly. This ensures instantaneous throttle response. Of course this fuel isn't metered, so some lunatic bureaucrat at the EPA had their head explode on them when they found out about this, and once they put his head back together, they promptly neutered the carburetors in jet skis after like the year 2000.

Of course all this would be solved by sticking a catalytic converter on there, but nobody in the inudstry did that for some reason. Also, in the real world EFI doesn't actually solve this problem, because the first thing cockspurter-riding wing-chung first-bike teenager does is bankrupt themselves by sticking an aftermarket exhaust on their bike, and then not having enough money to spend the ridiculous $500 or whatever it takes to make the bike not shit unburned gasoline out the back. GO GOVERNMENT!

It's actually tragic that all bikes are now saddled with this stupid technology which is great for like ships or trucks, but I'm dubious on cars and Bikes with EFI shouldn't have ever been brought into existence.
Just thinking about the prospect of a carbureted K1200S/K1300S has me purring like a cat, although to pull it off to the standards BMW could if they and the German government hadn't drunk the EFI propaganda cool-aid, is likely impossible.
 

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A carburetor will also work after an EMP blast
But the rest of the bike won't...
I disagree with the entire automotive/ICE industry on this.

At the very least for bikes. If they had put even 1/10th the effort/research into carburetors they put into stupid EFI, we would have absolutely incredible carburetors. I don't think there has been a carbureted bike with a catalytic converter. This would solve literally all tailpipe emissions issues. It would not solve the oh-so-scary and pointless gas evaporating issue that is the reason carburetors were even discontinued in the first place (not performance, fuel economy, tailpipe emissions, or anything else, it bears repeating)

See above all the shit that's actually required to get EFI to work, and then look at the myriad of posts on this forum about people having EFI issues; although they don't recognize it as EFI issues. They make posts like "oh this sensor issue, need a booster plug, need an O2 sensor, need power commander, need tune, need PhD in Computer Science to make it work, etc. etc. etc.". Somehow we've made bikes that can't do hot starts, but nobody actually attributes this to a fuel injection problem "oh it's a sensor issue". Pfff.

This isn't in any way better than what carburetors offered except maybe cold starts. I'm pretty sure the late model Japanese bikes that still had carburetors had electronically adjustable carburetors for altitude, The Yamaha YZF600R and Kawasaki ZZR600.

Also NOTHING fuel injected can match that analog throttle response you get from a carburetor. NOTHING. People content with EFI are people content to live in a simulation. Blue pill. With carburetors, you pick up on the tiniest nuances of your engine. You become one. It's 100% a thing, and it's TRAGIC that whole generation of people will never understand just how fantastic carburetors are because they have swallowed the fuel injection propaganda. What's even more tragic, the throttle response could be even better, but the EPA nixxed that on carbs because they hate happiness. My friend's jet ski has little dump valves that pour gasoline directly into the intake whenever you squeeze the throttle quickly. This ensures instantaneous throttle response. Of course this fuel isn't metered, so some lunatic bureaucrat at the EPA had their head explode on them when they found out about this, and once they put his head back together, they promptly neutered the carburetors in jet skis after like the year 2000.

Of course all this would be solved by sticking a catalytic converter on there, but nobody in the inudstry did that for some reason. Also, in the real world EFI doesn't actually solve this problem, because the first thing cockspurter-riding wing-chung first-bike teenager does is bankrupt themselves by sticking an aftermarket exhaust on their bike, and then not having enough money to spend the ridiculous $500 or whatever it takes to make the bike not shit unburned gasoline out the back. GO GOVERNMENT!

It's actually tragic that all bikes are now saddled with this stupid technology which is great for like ships or trucks, but I'm dubious on cars and Bikes with EFI shouldn't have ever been brought into existence.
Just thinking about the prospect of a carbureted K1200S/K1300S has me purring like a cat, although to pull it off to the standards BMW could if they and the German government hadn't drunk the EFI propaganda cool-aid, is likely impossible.
Hmm. I'm stepping back from this.
 

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This seems to suggest that the zzr600 DID have a catalytic converter
Carburettors by their extremely simple nature are likewise extremely limited by what can be done to them unless all the electronic wizardry that applies to EFI is applied to carburettors.
Misapplied or incorrect logic is the only thing that I can see that can make carburettors better than EFI.

Conspiracy theories never will 😳
 

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No such carburetor kit available for k120Os. You would have to melt down aluminum and mold of your own, thereafter design a throttle system to adapt, would be interesting.
Last carburetor car I had was a Alfa Romeo GTV with dual Weber’s if I recall, fun car when carbs were tuned properly, oh and not to forget my Volvo 145 also dual carburetors, add Manual trans and you have a near perfect auto that you can still work on yourself.
Miss those cars and way Better than it’s modern day plastic and wire counterpart.

Maybe this carburetors setup can be modified to work on the current k1200s velocity stacks, it is a thing of beauty!
Photograph Train White Yellow Font

Or even this set up!
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Discussion Starter · #39 ·
Did you find a workable solution? Probably had to fashion something I figure. Sorry it's off topic.....just curious....
Take the shotgun apart into two pieces, fold the case over, strap it on the back seat orthogonal to the line of the bike.
I didn't want to take the shotgun apart at first, but it's actually really easy.
 

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Thanks for the laugh Chicken.
That's the funniest thing i have read for a long time.

Think of the job of the fuel delivery system as separate to the air control system and you will see the weakness of carbs.
Carbs use the vacuum that they create in the air flow to control fuel delivery.
Throttles do not need to artificially create any vacuum to control fuel delivery, so a wide open throttle is wider open than a wide open carb.
Also carbs are way more complicated than EFI. Carbs can't handle high intake pressure without maintaining a pressure differential - K1200S uses positive intake pressure as speed.
You could make a carb set, but it would be a significant performance drop - but that is the only downside.
 
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