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How much of a difference is there between having fuel injection vs. a carberator on a cruiser?

Well the startup procedure with a carburated bike means you have to use the Choke on most occasions. Also you you don't get a fancy low fuel warning light. Instead of rejetting when you add an exhaust or intake for carb bikes, you have to reprogram the ECU with a PC or FI. uh, all I can think of ATM, but I'm sure others will add.

Some stuff I found ol... Someone might know more...

Maintenance-wise it's a bit of a wash. FI should be cheaper in the
long run, because they have a lot fewer moving parts than carbs. But
FI also requires pressurized fuel, which means FI bikes have to have a
fuel pump. Carb'd bikes don't. Carbs have also been around for so long
that there are lots of very reliable carb designs that a bike manufacturer
can slap onto a bike and forget about. FI usually takes some R&D and
fine-tuning. An FI bike will also have more sensors to monitor the
engine than a carb'd bike. If they go bad, they can be expensive to
replace.

FI bikes should have slightly better emissions and somewhat better
throttle response than carb'd bikes because they can be a little more
precise in fuel dosages.

Carbs don't work well when they're on their sides or upside down,
and will generally stop an engine shortly after a crash. FI bikes can
stay running for a long time after a crash. Though some manufacturers
put a tilt sensor in their FI bikes to cut the engine in the event
of a crash.

Re-tuning a carb'd bike after putting a better exhaust system on
usually involves taking the carbs all to pieces and putting in different
jets to allow more fuel to flow in. An FI bike may be able to adjust itself
for a freer flowing exhaust, or you may have to hook it up to a computer
to tune it.

From what I can gather, EFI is a lot easier to tinker with (in terms of
remapping, as opposed to re-jetting). I personally haven't been able to
tell the difference between the current fuel injected and carbureted bikes
I've ridden. That's probably because I haven't ridden them for too long,
though. It seems to me that people choose EFI mainly for modification
advantages. I could be wrong.

One area EFI is definitly better is in dealing with weather and
altitude changes. The higher in altitude you go the less air there is.
If you don't adjust (reduce) the amount of fuel you are putting into
the combustion chamber you will end up "running rich". This simply
means the air to fuel ration is out of balance. Carburators can't
adjust for more or less air. They keep putting the same amount of fuel
into the combustion chamber regardless of the amount of air there is.
The only way to change this is by manually replacing "jets" and other
carb tweaks.

I live near Seattle and we have plenty of mountains around here. I've heard of guys taking their carbeurated bikes into the mountains, stopping for a break and then when they go back to start their bikes they won't start because of the altitude change. What do you do then? I don't imagine you're going to be carrying a spare set of jets and the tools needed to tear apart your carbeurator.

What earwig said is mostly right.

However,
My 1984 Interceptor is carbed... it has both a fuel gauge AND a fuel pump. Same thing with my 1994 Interceptor.. carbs, fuel gauge, and a fuel pump.

So having carbs and a fuel pump and/or fuel gauge are not mutually exclusive.

The main differences (as already pointed out): Fuel Injection is more precise, it is easier to change/alter maps than it is to re-jet. If you have to do a full clean on carbs for any reason, it is a pain in the "O Ring". Carbs effectiveness changes based on the altitude, so you might have to re-jet if you change altitudes.

If you had a choice between carbs and FI, I would pick FI.

EDIT: Gimpster, you just turn on the choke.

If the altitude is really high, choke is bad. The problem is that mixture is already too rich... enriching w/ the choke makes a bad situation worse.

My ninja is trickier to start (from cold) at home (4400' MSL) than at the office (500' MSL). The difference is that you can seriously overchoke at the higher altitude and it won't run at all at that point. Starting at 4400'MSL involves gently easing the choke out while *slightly* cracking the throttle... too much of either and it won't fire. You are almost better off with no choke at all, though that makes it hard to get the motor up to speed. Choke or no, it is very sensitive to additional throttle just after starting... takes finesse to get it up to 2000RPM the first time and I've killed it a number of times by opening the throttle too abruptly. At 500'MSL, you can pretty much hit the starter as you ease the choke out around the 1/2 way mark and it'll fire in a rev or two. A blip of throttle to get it up to "oil pressure light will light this century" revs and you are good to go.

The real problems hit above 10,000'MSL though. By 14,000MSL, there are a lot of carbed cars and such that will be pouring black smoke out the exhaust and barely running.

sharpmagna wrote:Also you you don't get a fancy low fuel warning light.

I have a carbed bike with a low fuel warning light.

FI = Start up & go. No choke no petcock. So much easier. New technology vs. old technology.

Should it be the deciding factor on buying a bike? Is old technology neccessary bad?

Diesiege is right. The last thing you want to do when starting a bike at high altitude is to choke it. It's already choked naturally .

If the bike was still running when you shut it off at high altitude, the most likely problem is that the spark plugs are either fouled or soaked with gasoline from the overly rich mixture. The quick fix is to remove the plugs, clean them off, reinstall them, start the bike, and go downhill very soon.

As for fuel pumps, bikes that do not have the fuel tank completely above the carb/FI system will need a pump to get the fuel from the tank to the engine. The type of fuel pump in an FI system is more than just a plain pump. It has to have the capability of regulating the fuel pressure to a very fine degree in order to provide just the right amount of pressure at the nozzle.