Fuel Injection

[tomwalshco]

I have a friend with a fuel injected bike and raves about the superiority over carb'd bikes.

Can any of you Suzuki gurus tell me which Suzi streeters have fuel injection and what year they started with that upgrade.

Thinking about upgrading and am always looking for a bargain, so I need to know what years/models I need to look out for on Craigslist. Thanks.

TW

[loudnlow7484]

Tell your friend he can suck a c***!



(c*** = carb, of course!)

[tomwalshco]

Wow, man - you look happy in your picture.

Actually my buddy has gone through the agony of Harleys with the carb ****, but now has a big, new Harley roadie with F.I. and is in heaven. If carbs were so good, then why are all the NASCAR, Cafe, Bike Racers and and any other motor sport racing community doing FI?

And also, it appears all the newer Suzuki streeters are FI. Must be a reason.

[GytRDunKat]

Nascar isn't fuel injection, good ol fashioned carbs, btw

[loudnlow7484]

I am happy.

Anyway..... carbs and fuel injection both have their issues.

Fuel injection nowadays is pretty good, for the most part. There are still bikes that have some low-speed part-throttle issues. The earlier FI bikes are known for being a little.... eh.... "glitchy" I guess is the best word for it. They also require computer mapping for any sort of big modifications.

Carbs need to be tuned. It takes a competent person to tune them correctly. Personally, I like carbs better (sound of flat-slides rattling gives me goosebumps), unless you're going with some sort of forced induction... then fuel injection is a much easier way to go (in my opinion, of course).

Cafe bikes are fuel injected, huh? This guy ( http://www.cb750cafe.com ) makes some of the coolest cafe bikes I've ever seen, and they're carbed. I haven't seen any FI cafe bikes, but I can't say I'm heavy into that scene, so I wouldn't know.

[arsenic]

there are all FI now because of the EPA, that's the reason

[philwecksr]

the gsxrs switched in 2001 I think....

Or you could do like TheSteve and me and drop 600 or so and have a fuel injected kat!!

[CarolinaRebel02]

How exactly would you go about fuel injecting a Kat Philwecksr? Please explain...

[philwecksr]

Mwahahahah with pleasure....

http://katriders.com/vb/showthread.php?t=84789

Check that out, TheSteve and me are both in process, although he is much further along than I. I've run into some other mechanical issues at this point (stupid valves) but I hope to wrap it up over the winter...

[LORDMETAL]

it's not a cafe if it's fuel injection
i'd like to build one like this some day

[The CyberPoet]

Actually my buddy has gone through the agony of Harleys with the carb ****, but now has a big, new Harley roadie with F.I. and is in heaven.
And also, it appears all the newer Suzuki streeters are FI. Must be a reason.

loudnlow7484 & Arsenic hit most of them, but missed at least what I consider the single most crucial one...

The current and next-generation crop of EPA pollution regulations and the similar or identical Euro-3 and Euro-4 regulations all require that a bike remain in complaince with the required pollution standards for a period of 5 years or 18.6k miles (whichever comes first). While they can build carbs to meet the basic pollution output requirement, ensuring carbs remain in-spec for larger engines for a five year period is a particularly daunting task and the reason everyone is moving to fuel injection in the 250+ cc size classes.

[reposted from http://katriders.com/vb/showthread.php?t=69444 ]:
Carbs vs. Injection
The primary advantage to carbs is 80+ years of development makes for very smooth on-/off-throttle response and very reliable fueling. They are also simplistic systems by comparison (in a sense) and are easily field-servicable (a number of us, such as MD86, could tear down a set of carbs *anywhere*), and when they stop working right, they will usually still get you to your destination unless they are seriously mangled.

Fuel injection requires a pump to bring the fuel up to a high-pressure level, a controller of some sort to dictate when & how long the injector should be open, a host of wiring to support these functions. Most fuel-injected bikes from 2005 forward will also require some form of Lamda loop (o2 sensor feeding info back to the computer so the fuel amount can be "tuned" to the environmental & fuel-quality conditions perfectly). Plus, because of the fuel pump, most bikes with injection systems have to have a tilt-sensor safety switch to shut down the pumps if the bike flops over on it's side (a real PIA to reset -- some have to be replaced to reset them).

The advantages of fuel injection is primarily that there are far fewer moving parts, so there is usually less diagnostics/repair man-hours involved (standard practice is to replace rather than repair a defective injector or pump, where it's common to repair carbs). And unless retuned electronically, injected bikes are more environmentally friendly than carbs ever could be simply because they do stay in-compliance for longer. But most FI systems are much twitchier about on-/off-throttle transitions (this is getting better as companies tweak their systems more over the years, but the first decade of injected bikes often show spastic reactions when you first roll on/off throttle).

will bring their engineering expertise over with a few carbs to fine-tune the final result, as they've made 600cc transverse-4 carbs for various bikes for eons -- all they really need to know is the bore, stroke, valve sizes and they can match it.

On the other hand, let's say you want to go injection. Another call to mikuni (or one of the other vendors), and this time a few of your pre-production bikes (or at least engines) need to go to their config facility -- somewhere that has a bolt-on dyno in an weather-variable air pressure chamber that can vary the temp, the humidity, the air pressure (altitude), while putting wind over the bike (esp. if it has RAM). You have to tell them how many maps you're willing to pony up for in the final variation, and how much processing power you're willing to pay for.
Then they have at it, figuring out that at 65% relative humidity and 2000 feet elevation, with the throttle at 40% & opening, they need to deliver X amount of fuel. The number of discrete points to match & set are increadible. And once they map all these points, they have to figure out how many of them can be shoved into ROM's, and how many of them can be calculated -- given the limitations on ROM size (cost) and processor strength (cost/heat) limitations Suzuki set forth at the outset, while still keeping the bike below EPA-mandated (& Euro-3 mandated) pollution levels at all points.

This is where the basic data-processing technology really starts paying off -- the faster the processor, the more you can do as calculated variables. The larger the ROM firmware, the more basic maps you can store to start with (and the less processing power is needed) -- as long as the ROM's are fast enough to respond with all the data you need. Early fuel injected systems had a lot of throttle "snatch" because of limitations on memory size and processor strength -- as manufacturers dump more $$ into the electronic control side, the throttle systems start acting more like carb'd systems, with smoother transitions and less violent responses to opening or closing the throttle.

The late model R6's are a perfect example: while riders complained the '06 was a bit snatchy, a remap of the fueling maps and a slight boost of the processor speed makes the '07 much less snatchy -- but it's also a hair down on total power due to the same parameters.

Cheers,
=-= The CyberPoet

[SweetLou]

I like carbs. Esy to tune when doing mods, don't have to take it to a dyno, or get a computer remapped, just a few adjustments. Have pulled a bike apart at a KFC once to fix a leaky carb. IMO carbs area easier to tune, just require a bit of maintenace. But really not all that hard to do yourself.

And tell your buddy that ALL the gixxers and what not in the begging were carbed, and even the R1's were carbed up to like 2000 I think.

[ATOMonkey]

Wideband O2 systems have made dyno tuning a thing of the past.

The engine is constantly compensating for weather, altitude, mods, etc.

I would not hesitate to do anything other than a wide band O2 FI motor if I was starting from a clean sheet.

It also makes plumbing of the air system much easier. No more vacuum goofyness from putting pods on the bike. Dry manifolds can also have much more aggressive bends in them, giving you more flexibility in manifold tuning and design.

Just better all around. I'd say that FI is easier to fix and tune than a carb as long as you know your way around a lap top (or PDA) and a multi-meter. Those are the new tools that will replace the screwdriver and creasent wrench for shade tree mechanics.

[tomwalshco]

Are any of the Kats FI? If so, when did they start? Thanks.

[The CyberPoet]

The GSX650F that recently came out as the Kat-replacement is; no stock Katana is (there are a couple on here that FI'd theirs).

Cheers,
=-= The CyberPoet