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FI or CARBS

  • GIVE ME FUEL INJECTION

    Votes: 39 65.0%
  • I LOVE MY TRADITIONAL CARBS

    Votes: 21 35.0%

  • Total voters
    60
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perhaps it me, but why would anyone want carbs? they are easier to work on and lower costs to repair, but fuel injection yeilds better performance and smoother operation.
 

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fuel injection yeilds better performance and smoother operation.
Don't know about that. The best compliment one can give an FI system is that it is "carb like". CV carbs are incredibly well suited for smooth power delivery.

I think manufacturers use FI because it is more compact. Look at a rack of 40mm carbs some time. You can't make them much bigger because they won't align with intake ports any more. There just isn't enough space between the ports to make the carbs any bigger.
 

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carbs all the way. much, much smoother. but time marches on. and i'm sure within a few years the epa would carbs running so lean they would have no drivability.
 

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I'm going from info I have about cars when I made my comments, perhaps bikes are different, but on cars the fuel injection is most of the time larger then a simple carb. and it definately give the car smoother power and better economy, as well as prevents any lean conditions because of the sensors. I can only see advantages over the carbs, but what do I know, I've only dealt with cars up until recently
 

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Discussion Starter #7
I called Kawasaki's main office here in the states and spoke to a technical representative. He says FI is far superior to the CARBS. Does he know what he is talking about, or is this some sales pitch???

We are talking about for every day commuting, twisty, road raging wheelies.

Not for track purposes, now which is better or would you prefer FI or CARBS.

For year round conditions also.
 

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As Bill Clinton would say, depends on your definition of the word "superior"
 

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Kind of depends on the bike, don't you think? My ZX12R works perfectly with the FI, and it also has a Power Commander III and a full Akrapovic system. My ZRX works perfectly with carbs!

Harleys, in my experience, are MUCH better with the FI.

Having the mechanical ability of a footstool, I try to do as much of my maintenance as possible with a checkbook. It took me 30 years to discover that I save both money and time this way. With that background, any system that requires no maintenance is good for me.

As an example, I adjusted the chain on my ZRX today, and it was a comedy of errors. You would not believe anyone could make a 45 second job so difficult!

I owned a 1977 Yamaha XS750 triple for 22 years, and loved it. It always ran perfectly, and I never touched the carbs over 58,000 miles. A friend of mine just bought the same bike from the second owner and needed to spend some time on it, because the guy had "adjusted" the carbs so that it would hardly run.

In coming years, as computers continue to get more complex, and cheaper, I think all bikes will have FI, and they will all run perfectly. Garage mechanics everywhere will then complain that they cannot "improve" their bikes like in the good old days.

I have been riding for 35 years and the sum total of all of these experiences is that 1.) These ARE the good old days and 2.) Most people who work on their motorcycles really should not!

One caveat - I now work for a dealer, and I get to see my bike worked on and I know who is doing the work - life is good.

As for me, soap and water and wax are the only mechanical operations I enjoy - and the only ones I can do without endangering myself and the bike.

Yours in humility,
Dave Preston
 

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Carbs. They might not be "superior" in whatever sense of the meaning you prefer to take it, but you don't need a $15,000 computer to tune it.

FI is also volnerable to electrical failure. A race-mate's FI system was fried by "the shop" that was looking at a different electrical system, and refused to take responsibility. And yes, it was the shop, since he is not mechanically inclined, whips out the checkbook with each task, and it was working before he took it in.
 

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johnnyxpx said:
Hey Duc, which of your bikes do you enjoy using more for your daily riding needs?
The ZX9R.
 

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Well carbs are great, but if your are going to aftermarket exhaust, forget about it. Rejetting is a pain in the ass compared to a remap. FI is easier to meet smog with too.
 

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enki said:
Well carbs are great, but if your are going to aftermarket exhaust, forget about it. Rejetting is a pain in the ass compared to a remap. FI is easier to meet smog with too.
Yah but a pc3 is 3 times more than a re-jet and the map you use isn't 100% perfect most of the time either, still has to be tuned. I know that future changes are far easier but that first one's a bitch financially!!

I like carbs although it sounds like some bikes are coming out with decent FI, MANY of the first ones sucked. Maybe in a few years??? but for now I prefer carbs.
 

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besides the extra computer whats the difference on a bike between carbs and fi. I thought on a bike fi was similar to carbs in design, just used injectors instead of metering needles and stuff.

as far as tuning, yes it does cost more at first but the benefits are worth it, on a few of my old race cars we had custome fi set-ups which cost a nut. but with them we also had a program that allowed us to use a laptop and we could actually adjust each cylinder individually. we were sometimes able to squeeze an extra 30-40hp out this way and also make sure of no leaning conditions in just one cyclinder. in other words, I like it;)
 

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I like them both due to the fact that its easier to tune a turbo bike with an FI system. Then on the other hand i love the chatter of my FCR 39's. But as we all know, carbs will be replaced with FI systems...

marco
 

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SilentNEKO said:
besides the extra computer whats the difference on a bike between carbs and fi. I thought on a bike fi was similar to carbs in design, just used injectors instead of metering needles and stuff.
The easiest I've been able to describe the difference between carbs and FI is that basically, the needles used in carbs are "unprogrammable FI on a stick".

You get a generic FI-stick when you get the bike, basically programmed to meet EPA, and not suck too badly with the stock exhaust.

Then you get a re-jet kit like Factory Pro, Ivans, Dynojet or whomever is making needles anymore. These companies do major testing and countless dyno runs, "sculpting new FI-sticks" to result the best numbers possible. So the jetkits you buy are better tuned for your bike.

I hope that was clear, if not, I'll knock off the FI-stick analogy. :D

Sure, in the future, most if not all bikes will be replaced with FI. But like Apex said, that first upgrade is a bitch and I personally don't feel like spending a grand+ (PCIII and tune) for FI. How do I figure a grand?
- PCIII costs anywhere between $280-$320?
- decent exhaust, since you want to do this only once, about $500-600
- and I got a quote to tune my Ducati with a new chip (from Factory Pro) $675
- then I started playing the numbers game with various tuners (said I have a new GSX-R750 and PCIII. asked how much to tune), I was quoted about the same amount of dollars.

But that's just me. I'm picky about my bikes, and they all have to be tuned and running well. Sure, you can install a PCIII, download the map and go, but then, again, not all bikes, especially the motors, are not made equally, so a downloadable map is also pretty generic.
 

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Carbs. But I will take whatever they put on the bike from the factory.
 

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Fuel economy along with reduced emissions is the most part of why fuel injection was invented. I believe fuel injection is easier to work with but carbs give you that hands on experience, making you feel like you are the reason your bike runs better... FI also adjusts itself so thats a plus right there, but how many times have you had to change jets on your bike without modifications? Probably none.... I think for EPA standards FI is superior of course... Someone refered to cars and bikes and FI being sorta the same, well.... No not really... Same "basis" they work off of but once into the system they are a bit different.....
 

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Carbs: Use the jets outside the engine in an enclosed area, a box if you will. Carbs mix the fuel and air before it enters the cylinder.
FI: puts the jets straight into the cylinder.
Carbs are usually smoother as the injection is constant and all the cylinders get their mix from the same source (usually) while FI is a spurt of gas exactly when each cylinder needs it.
Since in carbs you mix the gas and air outside the cylinder there is a lag before it gets into the cylinder plus you cant control the mix as exactly. FI the computer can control the mix exactly as required that's where buzz phrases like 3d real time mapping and such and such bit computer systems come in (and why you can simply remap FI when you modify something (power commander)) . The better the computer knows what is happening the better the mix is. Thats why FI is crisper and more responsive.
Carbs are simplier and easy to fix but without changing the carbs themselves you cant really do much with them. FI you can simply reprogram.
 
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