Any thoughts on FI (Fuel Injected) bikes?

[87cr250r]

The "inorganic" feel you get from the FI bikes is from the oversized throttle bodies seen on sport bikes. FI lets the bikes run substantially larger throttle bodies than carburetors. The big throttle bodies make for the harsh transition between closed throttle and partly opened throttle. Manufacturers have attempted to deal with this in the past by using a second set of computer controlled butterflies above the primary set to smooth out the transition. More modern bikes have done away with the second set of butterflies and are drive by wire so the computer limits the rate you can open the throttle at.

 

[Caddywumpus]

David... Carbs run on old man magic.

 

[wakked1]

Most bikes have crap FI due to emissions requirements. That's why they have odd holes in their torque curve around 5500rpm, shut off fuel entirely at closed throttle until you drop to idle, and other weird things that have 0% with having the engine run right. I've had a bunch of FI bikes, but I'd recommend carb overall as it gives you 100% control over how the bike will run. Others will disagree tho.

 

[day004]

All of my current bikes have carbs, and it sure does make me miss just hitting the starter button on my 1000RR and not having to figure out what combination of choke and throttle I need to get the bike started as I am pushing it through the pits in full gear.

True ,My old 76 Yamaha XS500 had built in theft deterrent. If I didnt tell someone how tho start it , it was basiclly a rock with wheels.

 

[madsen203]

A litter FI bike will give you all the organic feels you need. Enough mid range to blow your panties off so you can stay low in the RPM.

 

[sliverstorm]

I love FI. Lift up the seat and push buttons on the Powercommander to adjust it instead of spending hours with needles and floats.

This is one of the many wins for FI.

The biggest thing carbs got going for them is simpler, cheaper and smaller, but this isn't an issue anymore for most bikes. They also are a bit coarser, and have a cool feel to them sometimes, but it's a fact that a carb can only ever be at BEST, equally as good as a (good, tuned) FI system. When it comes to the bleeding edge of performance, FI is where it's at.

I've come to think of it like this:

For reliability and the ability to fix in backwater locations, carbs (though this may change, and may have already changed, with us just being too scared to risk it. Most car EFI systems anymore need far less service than carbs)

For sheer performance and/or tuning, FI

For feel (I know what you're talking about- one of my bikes had that) carbs. FI feels soulless because it's typically much more precise- same as how F1 cars sound soulless to me. Magically fast, but no character in their exhaust note.

 

[Burning1]

Most bikes have crap FI due to emissions requirements. That's why they have odd holes in their torque curve around 5500rpm, shut off fuel entirely at closed throttle until you drop to idle, and other weird things that have 0% with having the engine run right. I've had a bunch of FI bikes, but I'd recommend carb overall as it gives you 100% control over how the bike will run. Others will disagree tho.

The ECU on an 04 GSXR (and others) can be re-programmed completely. The changes that can be made to fueling and behavior are virtually unlimited.

Stock ECUs can be rather restrictive for legal reasons. The aftermarket stuff gives you unbelievable levels of control over how the fueling system behaves.