FI Testing in Japan

I saw the pic in this months dirt rider of the YZF with fuel injection being tested by Yamaha in Japan.....maybe a 07 or 08 will come standard with FI? Wouldn't that be a treat that the idea of rejetting is gone....... :applause:

I thought that the AMA had a rule against fuel injection on dirtbikes..... And yes that would be awsome if we never had to rejet again. have you been getting this same crazy weather that alabama has been getting? How about the fact that it was 70 degrees 2 days after christmas. A 35 degree change in 2 days. Pisses me off, and screws up my futile attempts at jetting

When the big four from Japan tell the AMA that the bikes they are going to be racing, say in '07, will have fuel injection, they will have the choice to adapt to progress or loose the participation of 90% of the race teams that exist. They will change the rule.

Maybe no more jets, just lots of wires-maps-lap tops and schools to learn how to map.FI is not a fix all in Dirt bikes IMO.


I thought that with fuel injection, you didnt have to do anything, and that it automatically gives you the perfect air-fuel ratio every time, which is why fuel injected machines dont need chokes.

FI doesn't have a chock per say but they do have a fast idle. Put a pipe on my FI sport bike Bike went way lean on dyno needed a power commander with a new map to run, then picked up 14 hp.


It would be nice to not have to swap out the jets;but with fuel injection to change air/fuel mix you need a laptop/PDA. Also there are lots more things to break with fuel injection---I would rather have a plain old carb when something malfunctions 30 miles away from the truck.

FI would be sweet for MX! FI can be setup in any way imagionable. Either totally automatic, with completely manual maps, or any combination of the two. What they would implement on a bike to sell to the public is anyones guess, but I bet the final version will be better in most situations than a carb.

EFI is alway better than a carb. on any engine, at any time ...

a carb. is always a compromise, although some engines can perform as good with a carb. (like dragsters, stationary engines etc. ie. all engines designed to operate at a specific rpm)

as for jetting, its not possible for the EFI to adapt to a changed hardware (as new pipe and muffler) as it changes the volumetric effiency of the engine ....

of course it will be nessecary to have a lap-top (if yamaha even lets us play around with that) to alter the settings, but as always there will be a lot of aftermarket parts aviable ..

as for more parts breaking, many of the parts needed is already on your modern 4-stroke bike, in the ignition .. like the TPS, and i could guess that there some sort of temp. sensor in there to ....

bottom line, if you ever have your thottle in any other position than WOT, a EFI is good for you!

I thought that the AMA had a rule against fuel injection on dirtbikes..... And yes that would be awsome if we never had to rejet again. have you been getting this same crazy weather that alabama has been getting? How about the fact that it was 70 degrees 2 days after christmas. A 35 degree change in 2 days. Pisses me off, and screws up my futile attempts at jetting

oh yea I am getting tired of rejetting back and forth ..... every other day...

On the programming for FI - Do the roadbike guys do this that often.... :applause:

the ama allows fuel injected bikes in supercross if the bike is manufactured with fuel injection, they do not allow aftermarket fuel injection. i personally think fuel injection would be awesome and its been along time coming. :applause:

Definately a good thing, it is a natural progression. Probably will add to the initial cost of the bike though!

Yamaha has really good FI on their street bikes. It gives the "most responsive" feel of all the FI systems out there according to the magazines.

They use a diphragm type setup that allows for better feel on partial throttle openings than the other manufacturers. A big complaint of earlier FI systems were that they had an either On or Off feel to them. A much too abrupt in their delivery for alot of dirt riding applications.

FI is a great thing, IMO, think about it, whens the last time you had to mess with the FI in your truck? never, and they are also starting to put it on ATV's....i think its a great idea, and definatly coming

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