ran out of petrol at 80 miles/h

[Seb_43]

ChunkyMonkey (05/10/2008)

Kevsta (05/10/2008)

As for racing, carbs are easy to adjust than fi systems and will give a more consistent result in the hands of small team who cannot lug massive amounts to technical gear to race meets.

Bloody EU.

How did you work that out Kevsta?

How is it easier to faff about changing jets and needle heightscompared toplugging in a laptop?

i’m lost on that one too.

[Kevsta]

Seb#43 (05/10/2008)

ChunkyMonkey (05/10/2008)

Kevsta (05/10/2008)

As for racing, carbs are easy to adjust than fi systems and will give a more consistent result in the hands of small team who cannot lug massive amounts to technical gear to race meets.

Bloody EU.

How did you work that out Kevsta?

How is it easier to faff about changing jets and needle heightscompared toplugging in a laptop?

i’m lost on that one too.

FI systems can be incredible complex, how wide the throttle body is going to be, hole many holes on the injector itself, do you go for 1,2,4, 16 etc holes? Do you have a common injector for all cylinders, or one per? Do you have multiple injectors per cylinders with different amount of holes to get better response through the rev range?

What about sensors, or do you go with a basic injection setup with one mapping regardless of the conditions or do you go the hole hog and have fuel temperature, air temperature, anti knock, lamba sensors, engine coolant and oil temperatures sensors? What about fuel quality sensors? Do you have sensors for each cylinder or one to cover all of them?

What about direct or indirect injection? What about the fuel pump? What pressure do you run the system at? What effect with this have on the injectors?

Do you use continuous or pulsed injection delivery?

Do you shut off the injectors when the throttle is closed or do you keep the injectors on to keep the system wet? So when the throttle is opened again there is minimum hesitation?

With all these options you have to map out all the variables. If you are a small racing team it would be easier to just work on a carb.

[Seb_43]

Kevsta (05/10/2008)

Seb#43 (05/10/2008)

ChunkyMonkey (05/10/2008)

Kevsta (05/10/2008)

As for racing, carbs are easy to adjust than fi systems and will give a more consistent result in the hands of small team who cannot lug massive amounts to technical gear to race meets.

Bloody EU.

How did you work that out Kevsta?

How is it easier to faff about changing jets and needle heightscompared toplugging in a laptop?

i’m lost on that one too.

FI systems can be incredible complex, how wide the throttle body is going to be, hole many holes on the injector itself, do you go for 1,2,4, 16 etc holes? Do you have a common injector for all cylinders, or one per? Do you have multiple injectors per cylinders with different amount of holes to get better response through the rev range?

this is done at manufacture of the engine (99.9% of all race bikes are modified from a homologated model)

What about sensors, or do you go with a basic injection setup with one mapping regardless of the conditions or do you go the hole hog and have fuel temperature, air temperature, anti knock, lamba sensors, engine coolant and oil temperatures sensors? What about fuel quality sensors? Do you have sensors for each cylinder or one to cover all of them?

Again installed at time of bike build, and again, 99.9% of race bikes won’t have any of this

What about direct or indirect injection? What about the fuel pump? What pressure do you run the system at? What effect with this have on the injectors?

Do you use continuous or pulsed injection delivery?

Do you seriously think this kinda thing is adjusted at the track???

Do you shut off the injectors when the throttle is closed or do you keep the injectors on to keep the system wet? So when the throttle is opened again there is minimum hesitation?

Something logical…and something that can be pre determined on a dyno for £30 and a propper set up

With all these options you have to map out all the variables. If you are a small racing team it would be easier to just work on a carb.

You have gone into such intracacies here. The point being to manipulate fueling FI is a million times less time consuming and only takes a lap top and some ready made maps made by your favourite dyno man for very little money…oh and I am a small race team…and i haven’t got time to be fecking around with jets and fuelling. AND one of the reasons you are seeing 4 strokes outnumbering 2 strokes in the racing world is because its so much less hassle to run a 4 stroke, less rebuilds, less stripping and rebuilding, less fooling around with jetting etc etc. Tell you something tho…some of the cables needed to map fuelling can be anything from 200-1000 quid…ouch!! Thats what your dyno man is for though eh.

[ChunkyMonkey]

Kevsta (05/10/2008)

Seb#43 (05/10/2008)

ChunkyMonkey (05/10/2008)

Kevsta (05/10/2008)

As for racing, carbs are easy to adjust than fi systems and will give a more consistent result in the hands of small team who cannot lug massive amounts to technical gear to race meets.

Bloody EU.

How did you work that out Kevsta?

How is it easier to faff about changing jets and needle heightscompared toplugging in a laptop?

i’m lost on that one too.

FI systems can be incredible complex, how wide the throttle body is going to be, hole many holes on the injector itself, do you go for 1,2,4, 16 etc holes? Do you have a common injector for all cylinders, or one per? Do you have multiple injectors per cylinders with different amount of holes to get better response through the rev range?

What about sensors, or do you go with a basic injection setup with one mapping regardless of the conditions or do you go the hole hog and have fuel temperature, air temperature, anti knock, lamba sensors, engine coolant and oil temperatures sensors? What about fuel quality sensors? Do you have sensors for each cylinder or one to cover all of them?

What about direct or indirect injection? What about the fuel pump? What pressure do you run the system at? What effect with this have on the injectors?

Do you use continuous or pulsed injection delivery?

Do you shut off the injectors when the throttle is closed or do you keep the injectors on to keep the system wet? So when the throttle is opened again there is minimum hesitation?

With all these options you have to map out all the variables. If you are a small racing team it would be easier to just work on a carb.

Agreed Kevsta, FI systems are complicated in their design as you describe above, but nowhere in the above did you mention how simple and quick they are to adjust. Compare stripping out a bank of 4 carbs, changing jets, needle heights etc with plugging in a laptop and downloading a new map in seconds. There’s no contest mate.

[Steve]

I can adjust the fueling and timing in my garage on a wet Sunday afternoon with just an old laptop, a cup of coffee ! It’s quicker to boot the laptop, adjust the fueling and shut it down than it is to make the (proper) coffee

[Nonsense]

johnp (04/10/2008)

Ddin`t you get the red petrol light come on either.

My old hornet didn’t have a red light - I just had to fill up before 100 miles to be sure :w00t:

[oldguy]

Anita

Thanks for the sanity.