Race track fuel burn

[mwirrick]

Any racers out there have any numbers on how much fuel you use while racing? I finished my last race, and, for various reasons, removed the gas tank and it hit me that I had a lot more fuel on board than I needed to get through the race. Won't make that mistake again! Am going to measure the fuel in the tank more carefully in future--no more, no less than necessary! Curious from the get go, though, if anyone knows what the mileage is at full chat. Thanks for any input.
Mike

[csmith12]

Hey Mike! How goes?

Just over a 1/4 gallon is not enough hahahahah. It nets you watching the rest of the race from turn 9 at Putnam. I won't be doing that again either. I think Rick tried a full gallon and still ran out. lol

[tooblekain]

Hard to say.

I know with my D675, I can do 1.25 gallon and make a 6 lap race provided there were no red flags and restarts. I came back into the pits and my bike was bone dry after the race. Probably another 100 feet and my bike would have shut off.

For the Ninja, I did a 20 minute session which was about 6 full laps and I got about a gallon used.

[Aufitt]

Ive put 4 litres in a bone dry tank and marked the fuel guage with a line.

I know it will do a 15 minute track session, so 6 lap races with an in and out lap is safe.

One thing I noticed is it uses exactly twice the fuel my cbr did.

[rojoracing53]

I practiced Friday and Raced 2 races Saturday and 2 races Sunday all on one tank of gas. No refueling FTW

[zvonler]

Depending on the track, I've found that the racebike burns a full tank in two hours, give or take 10m either way. That rate has been pretty consistent, so you could probably take your race duration as a fraction of that to get an expected usage, then add a little for safety because the bike will start to cut out at full lean before the tank is completely empty (ask me how I know!).

[iZapp]

if you could possibly run at WOT max power (>12000 rpm) for an entire lap, you would burn 2 gal/hr. So, if you're pinned 75% of the time i'd guess maybe 1.5 gal per hour, or about 1/2 gal for every 20 minute session.

practically speaking, we can run a full trackday with a full tank of fuel. that'd be 20 minutes *7 = 2.3 hr. At 1.5 gal/hr consumption rate, that would equal 3.5 gal, which seems just about right considering the tank is about 5 gal.

here's the calcs:
25 hp
* 0.5 lb fuel/hp/hr --> approx BSFC (brake specific fuel consumption) of most engines running at WOT
/ (8.33 lb wat/gal
*0.74 lb gas/lb wat)

=2.0 gal / hr

[mwirrick]

Thanks for the great info., everyone. Every little bit of weight savings helps on these bikes!

[rc-rick]

I can tell you right now 1/2 gallon in 30 min WILL NOT WORK! Hell, 1 gallon for our 25 min race may not cut it. I had right at that in our 3 way battle and ran out. I run 1 1/2 to be safe. Drain the tank before the race and add the gas. I have done some changes to the bike. Ill be looking forward to Sept!

[2WheelGuy]

My stock motor gets right about 30mpg on the track.

[Rexbo]

Originally Posted by 2WheelGuy

My stock motor gets right about 30mpg on the track.

haha i calc'd it out once and it was ~34 mpg for me hahaha

better than an RSV4 on the highway