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Sorry I am new at this. What is the difference in the FI vs carb bikes. i am just want to know what are the advantages and disadvantages of the 2, because I am looking at the 07 and 08 Husqvarna and I'm not sure which will be better for me.

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Well in my experience it seems like FI bikes have more potential, they are simple to tune and you get a more responsive throttle. You can pull a ton of power out of a carb'd motor, but it takes more time, precision and work it seems like. First time i had a FI bike it was actually a quad (raptor 700R) and i loved it. Drop in your Power Commander and tune on the fly, so much simpler than replacing needles and rejetting.

Edit: FI bikes can stay leaned over on their sides witout leaking too. No problem with long wheelies or sitting at a weird angle in the back of your truck.
 

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I like card personally, well tuned it's like a bomb.

But FI is great to :

Carb are tuned to a given temperature and a given pressure (altitude), so it cannot be optimal everywhere.
FI is auto-tuned everytime... whatever your altitude, temperature etc... so it works better.
 

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FI is inevitable and has its benefits. 95% dont understand how to accurately jet or keep a carb jetted threw out the day to keep the bike 100% perfect.

How many Drag Race/NASCAR/Stock car racers run FI??? I think there is more power to be made with a carb "if" you know how to set it up and keep it properly tuned.

.
 

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FI is great. However, don't confuse the EFI on SM bikes as the same as a new car or truck. These are very simple throttle body injection units with minimal inputs from sensors. They will carry power better than carbs over wider ranges of conditions. Despite many peoples adversion to FI, they are much easier to tune: with a PC not a wrench.
 

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They are both good, but FI is better, it can tell actually tell if to much fuel is being used then it reroutes the fuel back to the tank.
it won't reroute fuel in the way your thinking of. the correct amount of fuel that needs to be injected is constantly being calculated by the ECU so it'll never use too much fuel in that respect, once the fuel is sent to the injector there's no going back.

when fuel is sent back to the tank this is what happends: first the fuel is being pumped from the tank to the fuel distributer. once the fuel is in there it can go 2 routes, either to the injector which will inject the mixture into the motor or back to the tank through a pressure relief valve, this valve opens when pressure needs to be regulated inside the distributor. the injectors in a motor don't spray mixture continuously while the fuelpump keeps sending fuel to the distributer. there has to be a way to control the pressure inside the distributer, that's where the relief valve comes in. through that valve fuel can return to the tank and this way pressure can be altered inside the distributer.

about injection on our kinds of bikes, when done properly it's a step forward but at this point I still prefer a carb myself. you can work on a carb yourself and on our type of bikes I think a carb is still more reliable then injection, especialy since EFI on single cilinder motors hasn't been around for that long so it's possible you'll still encounter some kinks on some bikes. when a carb fails you can try and fix the issue on the spot since carbs are mechanical devices which can be worked on with simple tools. if the FI fails you're done riding, I don't think anyone here packs a laptop just in case they need to read out faults that went down with the FI unit, plus in some cases having a laptop on hand still won't fix the problem. FI depends on loads of sensors to calculate the correct amount of fuel that needs to be sent to the injector. if one of those sensors fails chances are the bike will run like crap or not run at all. those are a couple of cons imo.

pro's: FI will work with more precision when it comes to fuel delivery, it just works more accurately compared to a carb. there's more (fine)tuning abilities, you can just about alter anything to make the engine perform better, but this requires backgroundknowledge and the proper equipment, in this case a laptop with the right software rather then a wrench or other tool.

what will be better for you pretty much depends on you and the bike in question. there's some bikes out there where the EFI implementation didn't go so well and as a result the bike either won't run that well or you'll experience some glitches. don't think the 610 husky is one of those bikes but just to be safe ask around and talk to some owners if you want more insight regarding that subject. about the "you" part: let's say for instance you mount a pipe on your bike and you want to be able to set it up correctly yourself then a carbed bike is the way to go. if you don't mind a visit to the dealer so they can set it up (upload a new mapping etc), then you might as well go with the FI version.

Despite many peoples adversion to FI, they are much easier to tune: with a PC not a wrench.
true, but there's still something negative involved. stock bikes need specific equipement that's manufacturer related in order to get into the bike setup. as an average joe you won't get hold of that equipment so if you want things changed it usually ends with a trip to the dealer. the only way you can start tuning or work on the bike yourself is by implementing hardware (like a powercommander) that will allow you to get into the setup of the bike, that hardware can be controlled with software programs you can run on your own PC.
 

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Skully pretty much hit the nail on the head. Sometimes finding maps is cake. For my old car i had a program called DSMLink, and you could tune just about every aspect of the motor (A/F ratio, knock, retard, timing) and you could find maps based on what kind of modifications you have done to the car. The DSMs had a pretty big following, so maps, help, and advice were plentiful. On the other hand i had a Dobeck style controller on my Raptor 700R that you didn't need a computer for, no maps just simple adjustments. It had 3 buttons to control fuel, one for idle, mid, and WOT so you pretty much had to butt dyno it. I would stay away from a FI bike that required a PC and different map settings if you don't know what your doing. It can be a real pain in the ass setting 50 different things trying to find a custom map, because i doubt that there is that much support for the 08.
 

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The best thing is, a FI motor will be able to work in -40 conditions and +40 conditions with out altering anything, its all automated. I want to get an 03 Arctic Cat F7, which is powered by suzuki and has FI no jetting required. Or maybe skidoos Direct Injection 2 Strokes, that is the future.
 

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How many Drag Race/NASCAR/Stock car racers run FI??? I think there is more power to be made with a carb "if" you know how to set it up and keep it properly tuned.

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slightly off topic, but to answer your question..

everyone in professional racing who does not have it specificly outlawed, uses EFI.

top fuel, funny car, Ect -- NHRA / IHRA specifically says no EFI.. some still run mechanical fuel injection, depending on the class.

NASCAR has EFI outlawed... carb only is much easier to police.
 
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