Carbs vs. FI, which is better

[localhost]

...because after asking what im about to ask nobody will probably talk to me anymore :oops:

Well before i get kicked out of here:

I don't even know how to ask this.
i want to know about fuel injection and how much difference it makes in a bike.

I know you don't need the choke if you have fuel injection, but surely it must do more than adjust the fuel input?

Some bike adds i look at i see all this about fuel injection and i get the impression it's something fantastic, and it's not worth having the bloody thing if it isn't fuel injected.

Now, having a 2000 years model (k1? i thought k1 was 2001 but ive been told otherwise, now im just not sure about anything) i know i don't have fuel injection, but i was thinking about the next bike purchase im making.
Should i go for something that is fuel injected or is it not that much a difference?

Sorry if this is all obvious to you lot, but i'm just not terribly clever when it comes to bikes . :oops:

[stewboy]

just menas the acceleration may be very very slighty better, and maybe a bit mre fuel economical but no nothing specal really IMO.


i mean yeah if i had achoice i would choose the fuel injected but again nothing special.

[Lissa]

We're the opposite..............tried our mates fuel injected SV and thought it felt flat and gutless................carbs for us every time. :D

Horses for courses I guess............thank God we all have our differences.

[RandyO]

carburetion is the tried and true method of mixing fuel and air for combustion in the internal combustion engine

electronic fuel injection is the modern way of mixing fuel & air, it's more efficient and more customizable

[Red ones]

Right.

The reason newer engines have it is nothing to do with acceleration, power or anything as brutish, masculine, or "mine performs better than yours" It is purely and simply to get round emission laws. Emission laws have now got tight enough to almost ban carbs. The engine must run clean across a wide power range and over a large part of it's life. Carbs have difficulty delivering the right mixture across a wide range and do go out of adustment, so FI is the answer. The ECU can control the FI unit far better than any mechanic with a screwdriver ever could with a carb.

It does pave the way to then have electronic throttle controls, which do a lovely job in smothing engine performance across the power band blah, blah. blah.



I'll put my head back down now.

[Sid Squid]

The reason newer engines have it is nothing to do with acceleration, power or anything as brutish, masculine, or "mine performs better than yours" It is purely and simply to get round emission laws.

Partly true, the emissions are improved on closed throttle particularly, (over-run), in other circumstances as long as your carburation is set and adjusted right FI won't offer a significant benefit over carbs.

electronic fuel injection is the modern way of mixing fuel & air, it's more efficient and more customizable.

That's a better way of describing it.

PS. When in doubt then IB is probably the right place, I'd say this was bikes talk etc etc

[localhost]

I see.
So nothing increadibly awesome then.

Well, suppose it's nothing i should be TO bothered with then.

Thanks alot for the answeres.

[Diveboy]

Carbs are smoother as the fuel is gravity fed not forced in like on the injector models. I have had a (00) and an (04) bike and I can say that performance wise there is not much difference. I think I might even prefer the carbs over the injection system but as I ride in winter the new bike is a little better in the cold.

If your happy with your bike then keep it, you wont get anything more than a slighly better looking bike by getting a pointy with EFI. :oops:

[Sid Squid]

Carbs are smoother as the fuel is gravity fed not forced in like on the injector models.

Not so, the specifics of any given machine are to do with how it's been set up, in the case of the SV the carbed bikes aren't smoother at all, but, and this is the important thing, if the balance is off, due to the fact that the FI bikes have a much lighter throttle action, it can be difficult to ride right, if that's the case it needs fixing.

[Scoobs]

Don't get carb icing with FI.

[hall13uk]

FI i better of course :roll:



i of course base this on the fact that i own an FI

:wink: :wink:

[wyrdness]

electronic fuel injection is the modern way of mixing fuel & air, it's more efficient and more customizable

Modern? Fuel injected diesel engines were common in the 1920s. The Messerschmitt Bf109 had fuel injection in the 1930s as FI isn't affected by high g-forces, unlike carbs.

[wyrdness]

There are strenghts and weaknesses of both carbs and fuel injection. Most bikes now have FI because of emissions laws. Some people prefer carbs because they're (generally) smoother, are simpler and can be set up easily. Others prefer FI because it doesn't suffer from icing in cold weather and doesn't require a choke for cold starting. Having had several bikes with each, I don't have any strong preference.

[Flamin_Squirrel]

electronic fuel injection is the modern way of mixing fuel & air, it's more efficient and more customizable

Modern? Fuel injected diesel engines were common in the 1920s. The Messerschmitt Bf109 had fuel injection in the 1930s as FI isn't affected by high g-forces, unlike carbs.

All diesel engines are fuel enjected, and they've been around since the late 19th century.

I dont think it's true to say carbs are less complex either - certainly comparing modern carbs to modern FI, FI is cheaper and easier to make, so I understand (although maybe wrong).

[Sid Squid]

electronic fuel injection is the modern way of mixing fuel & air, it's more efficient and more customizable

Modern? Fuel injected diesel engines were common in the 1920s. The Messerschmitt Bf109 had fuel injection in the 1930s as FI isn't affected by high g-forces, unlike carbs.

True, but Randy said 'electronic fuel injection' which is the difference. We had a period of what you might call 'electric fuel injection'*, which was in principal the same, but the control was no-where near as fine, The earlier systems were mechanical, and often no improvement over the contemporary carburation, especially when worn.

It might not be realistic to refer to fuel injected diesels, suggesting a difference, all diesels are injected that's how they work, the earlier ones had mechanical systems, likewise some petrol cars of the seventies had mechanical FI.

I like the badges on the back of Range Rovers: TDi, as if that means it's a better one than the non injected version, I wonder how that works? Perhaps I could put some badges on my bike that say: ZX6-Rp, (pistons) or maybe SV1000c, (crankshaft). :roll:

*eg Bosch Jetronic, which had lots of mechanical parts and wasn't very good, the airflow sensor in particular was a flap that effectively worked in steps, not very accurate control at all.

[northwind]

Personally I reckon that in the case of the SV, in standard trim the carbs are better than the FI. I've ridden 3 or 4 carbed SVs and 3 injected SVs and while they did vary a little, overall the carbed ones had better low-rev power delivery, and crisper throttle response. Carb icing is the main downside- and it can be a real pain, though it can be worked around with a little planning.

A lot of people seem to get confused because of the injected model's extra power- but the injected model's hotter cams account for that.

There's other advantages and disadvantages though. FI is as adjustable as you want it to be, but at a price, while carbs have less fine-tuning potential but can be adjusted with a screwdriver and £4 worth of jets. If you have the hardware, the adjustability of FI is far superior- but you either need to have it done professionally, or you need to buy a PC and also have the hardware to program it. Does that drawback outweigh the advantage of the adjustability? I'd say so.

Also, FI failure is usually digital- it's either on or it's off. Carbs have a curve of failure, they can go a bit wrong and you can still get home. This is balanced against the fact that FI goes wrong relatively rarely.

Good FI is better in just about every way than carbs... Real-time feedback makes it a one-sided contest. But so few bikes have that level of feedback just now. Too many bike with FI have not just dumb FI, but not very good dumb feedback.

[DanAbnormal]

Blimey!

You guys and your history lessons eh?! :D

At least I learnt something new today.

[mburnstead]

I like the badges on the back of Range Rovers: TDi, as if that means it's a better one than the non injected version, I wonder how that works? Perhaps I could put some badges on my bike that say: ZX6-Rp, (pistons) or maybe SV1000c, (crankshaft). :roll:



Doesn't TDi in that instance refer to direct injection, as opposed to indirect injection? Because there is a significant difference between the two types...

Mike

[Sid Squid]

I like the badges on the back of Range Rovers: TDi, as if that means it's a better one than the non injected version, I wonder how that works? Perhaps I could put some badges on my bike that say: ZX6-Rp, (pistons) or maybe SV1000c, (crankshaft). :roll:



Doesn't TDi in that instance refer to direct injection, as opposed to indirect injection? Because there is a significant difference between the two types...

Mike

Indeed there is, in petrol engines. Diesels are direct injection. The TDi in this case refers simply to Turbo Diesel injection.

[kazglasgow]

Hello folks,

Standard? Dunno.

FI, for easy-peasy tuning plug in and play (yup, at a cost). Buy your PCIII with the right map, plug in , 10 mins later , better throttle response and maybe a touch more power.
Being a mechanical luddite and part of the playstation generation( wee white lie :wink: ) , Carbarattorors give me the complete heebie-geebies. :? Its a black art innit.............like chain adjustment!? :lol: Sound lovely open or with fancy filter tho'.

My VTR used to REALLY pop and spit when up at altitude, flames the lot. First time it happened I was waiting for the engine to explode. Never had this happen on FI'd bikes . Adjust themselves to altitude? Amazing eh? Your own VIC20 on yer motorcycle!

[independentphoto]

Indeed there is, in petrol engines. Diesels are direct injection. The TDi in this case refers simply to Turbo Diesel injection.

Doesn't the i when appended to diesel engines normally mean "Intercooler", referring to the set up whereby the turbochargers air output is cooled down to improve combustion and hence performance & economy?

It's all very confusing! Good ones are.......

SRi = "Sales Rep inside"
BMW = "Brainless Moronic W**nker" :toss:
X5 = Number of DVD screens distracting the (already inattentive) driver.


Back to the original subject however. For my money FI for it's reliability. Carb icing has iritated me a few times too many.

Garry :wink:

[Sid Squid]

Doesn't the i when appended to diesel engines normally mean "Intercooler", referring to the set up whereby the turbochargers air output is cooled down to improve combustion and hence performance & economy?

Well...it might, but I can think of a couple of TDi badged vehicles that aren't intercooled, and if car manufacturers, and more importantly car marketing divisions, had the opportunity for a bit more 'drive-way-one-upmanship' by sticking an extra badge on the back they'd take it I'm sure. There are plenty of 'intercooler' badges out there already, they'll be applied with the slightest provocation.

The 'i' got itself a little cachet twenty years ago when few cars were injected, (except the diesels of course), enough people are still enough impressed that we still have it even where it's effectively meaningless, like on a diesel.

[RandyO]

electronic fuel injection is the modern way of mixing fuel & air, it's more efficient and more customizable

Modern? Fuel injected diesel engines were common in the 1920s. The Messerschmitt Bf109 had fuel injection in the 1930s as FI isn't affected by high g-forces, unlike carbs.

True, but Randy said 'electronic fuel injection' which is the difference. We had a period of what you might call 'electric fuel injection'*, which was in principal the same, but the control was no-where near as fine, The earlier systems were mechanical, and often no improvement over the contemporary carburation, especially when worn.

It might not be realistic to refer to fuel injected diesels, suggesting a difference, all diesels are injected that's how they work, the earlier ones had mechanical systems, likewise some petrol cars of the seventies had mechanical FI.

I like the badges on the back of Range Rovers: TDi, as if that means it's a better one than the non injected version, I wonder how that works? Perhaps I could put some badges on my bike that say: ZX6-Rp, (pistons) or maybe SV1000c, (crankshaft). :roll:

*eg Bosch Jetronic, which had lots of mechanical parts and wasn't very good, the airflow sensor in particular was a flap that effectively worked in steps, not very accurate control at all.


Yes, I did say electronic, when I was writing the post at first I just had FI, but I figured somebody would say something about some 100 year old injection system, knowing they have been around as long as anything

my BMW 320i has one of the "mechanical" Bosch injections systems

[drumwrecker]

As I understand it, these days FI is controlled by an ECU which is another electronic gizmo that can suddenly go wrong and need specialised equipment to diagnose a fault etc and then cost an arm and a leg to put right.
I think I would prefer to stay with the old technology of carbs. I believe in the KISS principle.

[mburnstead]

As I understand it, these days FI is controlled by an ECU which is another electronic gizmo that can suddenly go wrong and need specialised equipment to diagnose a fault etc and then cost an arm and a leg to put right.
I think I would prefer to stay with the old technology of carbs. I believe in the KISS principle.

True, it can go wrong, but in reality ECUs seldom do - solid state electronics are very reliable. And at least you CAN diagnose a fault - usually by plugging in a laptop and pressing a button. You can't do that with a carb - but I do take your point in the case of a mysterious breakdown miles from a dealer.

Carbs are definitely not without fault - it's very hard (impossible?) to set them up to fuel at peak efficiency at all points in the rev range, they are prone to icing in cold, damp weather, and they require more maintenance. And don't forget they've have over a century of development - EFI has only been used in anger on what you might call 'normal' road bikes in the last few years.

[Last Action Pimp]

Don't get carb icing with FI.

well done scoobs you have just said what i was going to say!

[empty]

I like the badges on the back of Range Rovers: TDi, as if that means it's a better one than the non injected version, I wonder how that works? Perhaps I could put some badges on my bike that say: ZX6-Rp, (pistons) or maybe SV1000c, (crankshaft). :roll:



Doesn't TDi in that instance refer to direct injection, as opposed to indirect injection? Because there is a significant difference between the two types...

Mike

Indeed there is, in petrol engines. Diesels are direct injection. The TDi in this case refers simply to Turbo Diesel injection.

You can have indirect injection in diesel engines - see Here (http://en.wikipedia.org/wiki/Diesel-engine), although I would imagine this is rare in cars. TDi is used by Volkswagon to describe their common rail (and turbocharged) diesel engine, it's just a brand, like Ford TDCi and all the others.

Ain't Wikipedia Brilliant?

MT

[Sid Squid]

That's not indirect injection, it's injection into a pre-combustion chamber, which is part of the cylinder volume and thus not part of the induction system, which is entirely different.
The problem here is that the language used is best suited to petrol engines, not diesels.
Direct injection = fuel goes into the combustion chamber, (or part of it - as the example above).
Indirect injection = fuel is fed into the induction system and passes into the cylinder already mixed/mixing with air.

To further confuse the unwary, there was a bunch of petrol engines, (H*nda perhaps), that employed a similar principle to the pre-combustion chamber of the above mentioned diesels, in that case it was labelled a stratified charge, as the induction gas was initially burned in a rich mixture part of the cylinder volume.

[Well Oiled]

True, they are all trying to 'out badge' each other but the TDi is meaningful in that it refers to Turbocharged Direct Injection, which VW used to differentiate themselves from the predominantly Indirect Injected diesel engined cars in the mid 90's.