Fuel useage under race conditions

Hi all,

I am currently working on an SV650 drag kart project, the kart has the standard fuel tank which I think is something like 7 or 8 litres, which is use for lap after lap on track. I will only be doing a 1/4 mile drag race and a bit of idling and waiting around in the queue for my turn to run.

I am therefore thinking about simply fitting a smaller tank, I am running a 12v solid state fuel pump rather than the vacuum fuel pump the SV usually has due to the location of the tank in the kart ie below the engine.

I am just wondering how much fuel is used on race bikes when racing full throttle so I can select the right size tank so I don't have issues with running low of fuel lol

Here is my build thread if anyone is interested

http://forums.sv650.org/showthread.php?t=174249

I have a stick....That sounds a bit wrong.
I have one off these free paint stir sticks in wood, and started with a empty tank, filled 1 liter, put stick in tank, made mark with knife, filled another liter etc etc, I start out with maybe(depends on duration, put normal is 20min) 5-6 liter on the first pass off the day, measure when I get in and go from there, try to leave 1 liter left when I get in, just incase.

Originally Posted by speedyandypandy

I have a stick....That sounds a bit wrong.
I have one off these free paint stir sticks in wood, and started with a empty tank, filled 1 liter, put stick in tank, made mark with knife, filled another liter etc etc, I start out with maybe(depends on duration, put normal is 20min) 5-6 liter on the first pass off the day, measure when I get in and go from there, try to leave 1 liter left when I get in, just incase.

Ah ok, I might just fill it with a few litres and drive it around a bit once its built and see if it drinks fuel or not lol the main issue is that the tank sticks out on each side of the steering column, I will be ofsetting the seat a bit so the bit that sticks out might make it unconfortable to drive so I guess I could just get a thinner tank custom made or something.

we used 10 litres at snetterton in a 45 minute endurance race 200 cicuit around 32 laps 64 mile if that is any help carby by the way

That seems to work out at about 29mpg lol hmm might mean I can run a fairly small tank then, I guess it will depend on how comfortable it is with the tank where it is, thanks for the info, you see all the normal fuel useage reports but not regarding how much they use during racing.

Originally Posted by m1tch_1987

Ah ok, I might just fill it with a few litres and drive it around a bit once its built and see if it drinks fuel or not lol the main issue is that the tank sticks out on each side of the steering column, I will be ofsetting the seat a bit so the bit that sticks out might make it unconfortable to drive so I guess I could just get a thinner tank custom made or something.

I thought you where after a way to find out just how much it will drink on your small runs, just enough fuel to run the 1/4 mile, best drag people run out of fuel 1 yard after the finish line, for a small run down the drag strip and a little idle in que, maybe a burnout, a pint size tank?

Originally Posted by speedyandypandy

I thought you where after a way to find out just how much it will drink on your small runs, just enough fuel to run the 1/4 mile, best drag people run out of fuel 1 yard after the finish line, for a small run down the drag strip and a little idle in que, maybe a burnout, a pint size tank?

I currently have a standard kart tank so I will just get the engine running first - im going to have to rejet the carbs anyway due to the lack of exhaust silencing

I will drop to a smaller tank at some point, I doubt I am going to need 7 litres of fuel to get down the drag strip lol probably get scared when changing to 2nd gear lol

I am just researching into the sort of size tank I will need, there will be parts of the kart that will need changing and upgrading probably next year such as possibly an electronic quick shifter and maybe a cam swap etc

thanks for all the input on this though, this is a really helpful and friendly forum

You can dedicate your first win to the forum

Originally Posted by speedyandypandy

You can dedicate your first win to the forum

I will probably die from shock from the accleration half way down the drag strip, the forum can then auction off the kart to keep the site running

[jambo]

Originally Posted by davegixer1300r

we used 10 litres at snetterton in a 45 minute endurance race 200 cicuit around 32 laps 64 mile if that is any help carby by the way

At my last track day I averaged around 30mpg too (inters).

Obviously drag races are rather different, but you're not going to suck through 7 litres in a hurry doing short sprints.

Jambo