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Quick question. The manual says the tank capacity is 4.8 gallons. However, I've never been able to put more than about 3.2 gallons in the tank. Even if I wait til the needle is right at E, I still cannot put more than that in the tank. What am I missing?
 

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Quick question. The manual says the tank capacity is 4.8 gallons. However, I've never been able to put more than about 3.2 gallons in the tank. Even if I wait til the needle is right at E, I still cannot put more than that in the tank. What am I missing?
*sigh* I will be nice for this one and only time... Just think about it, when you fill it up, is the tank itself bone dry??? Also where are other places gas gets "stored" on your bike?
 

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Check your gauge with the bike parked on the side stand. The reading should seem about right, doing it this way. However, this method is useless while riding. I'm also betting that when it says E while sitting on the stand, you won't have a lot of miles before it really is E.
 

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It says "E" when you actually have about a gallon left....Notice there are four seperated in bold dash...they represent one gallon each. Where do they represent the last .8 gallon? thats the E. I looked in the gas tank out in the sunlight, and it seems a lot left over on the E.But E is just a warning to tell you to get more gas. I usually get 3.5 each fill up than the whole 4.8 gallons.
 

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mine is wierd it shows that i eat up the first half of my tank in like 20 to 30 miles but then stays at the half way for along time to make up for it i guess, anyone elses do that, its like it just doesnt like to stay at the f
 

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Mine has never been on F. When I fill the tank up, it usually shows about 3/4 full or so. There are issues with the fuel guage not being accurate. I do not pay attention to mine, I just use my trip odometer as a indicator along with looking down into the tank when I think it may be low.
 

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Mine is all over the place too. At about 30 miles it shows 3/4 tank. At about 80 it's almost to 1/2...then it stays there until about 150 miles and it's still close to 1/2. I think the fuel quantity indicator looks great but can't be trusted. No worries I always set the odometer and even tho my bike is new I know I can get 250 miles or more on a tankfull. Once I really learn the fuel consumption of the bike I'll know how far I can go for the type of riding. Too bad Kawa didn't provide a better indicator. Reguardless is a very minor gripe for me.
Bill
 

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Just think about it for a second. The gas tank is not the same dimension from top to bottom. It is narrower at the top, wich means less gass is held at the top of the tank and it's at it's widest at the middle so that's why you burn through the top half faster. Also, if you hold your bike upright when fueling you can fill it up all the way to full.
 

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First, consider that the fuel reservoir (i.e. gas tank) is not a cylinder, cube or other straight-sided container. It's not even a sphere, it is an irregular shape.

Second, the fuel gauge operates based on a signal from a mechanical instrument inside the gas tank. This is the "sending unit", and yes there are copper/metal contacts involved.

Third, the gauge itself (in dash) only translates current from the sending unit into an analog dial readout. It is basically a ohm's meter (measuring resistance). The amount of resistance (voltage) cause the dial hand to move.

Consider how the fuel level "sending unit" operates:

There is a float, that for the purposes of this discussion, moves basically up and down. As it moves up or down, it physically positions a "metal lever" onto a coil of copper/metal wire. The position of the metal lever on the coil increases or decreases resistance based on the contact point of the metal lever. It's similar to a variable resistor, rheostat, or potentiometer. Like on an old TV or radio, as you turn a knob, volume increases or decreases.

Ok, so, if you have say, exactly 4 gallons of gas in a bucket, or something non-irregularly shaped, you can take exact readings of the remaining volume of the container if you know the liquid level, and have measured how much it drops when you remove a certain amount of fuel. Say you remove 1 gallon of the fuel from the bucket. You have exactly 3/4ths the amount of fuel that you started with. Each gallon of fuel will decease the liquid level in the bucket by exactly the same amount that the removed gallon did. Now you can calculate exactly how much fuel will remain in the bucket when it gets to a certain height.

The sending unit, as I said before, moves basically up and down (it's actually an arch, or radius, but the metal lever pivots opposite the float, or it is attached to the float arm in front of the float arm pivot point). Calibrating such a device for use in a bucket is easy for the engineers. Values will remain constant, and each change in fuel amount will change the fuel height by a specific amount. Since your fuel tank is irregular, and not even remotely spherical, removing the first gallon of gas from a full tank lowers the liquid level by a certain amount. The second (or third) gallon removed changes the fuel level by a considerably different amount. There is a lot more fuel in the middle "4 inches" of the tank than there is in the top "4 inches". The volume of those two "sections" is considerably different. So the fluid level changes at a different rate, since we are actually removing fuel at a fairly constant rate (just what you are feeding the engine). This means that the float will take longer to traverse the fat spot than it will the upper and lower sections of the tank.

Therefore, I have three possible conclusions:
1. The Kawasaki engineering team in charge of designing the fuel sending unit did not correctly take into account the shape of the tank.
2. The Kawasaki team did not bother with such trivial things as designing the sending unit to exactly match the fluid level in the tank. After a few tanks through your bike, you will get used to how it reads. "E" means look for gas sometime soon, not "EMBARK".
3. The fuel gauge only operates correctly when the bike is on level ground and on the side stand. I didn't read the manual on how to read the gauge, maybe this is correct, maybe not. It is true for my bike, but only at either the FULL or EMPTY extremities of the gauge. The fat spot is still a fat spot.

Personally, I "use" a combination of conclusions # 2 and #3, whether they are accurate or not. I keep track of my trip odometer for every tank (to calculate mpg), and I hate to think of what the price of the bike would be if the kawi engineers and sending unit manufacturers spent the time and money to get the gauge to be exact.

Now, you've gotta decide which option you like the best.

'nuff said.
 

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gas guage question...

hey guys i just wanted to ask you if your bike's gas guage reads right? when i fill my 2008 250r up it reads that it has only "half-full" on the gas guage. the guy i bought it from says they aren't very accurate gas guages and it still has about 1/2 left when it says empty. are you guys having the same problems? and if you are is there an easy way to fix it? also i just wanted to throw a question in here of what is the actual 0-60 time on a 250r i keep hearing anywhere between 8-5seconds... does anyone know which one is right? thanks for the help ^_^
 

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Hi InsomniacGamer,

The gas gauge on my bike seems reasonably accurate. I've filled her a few times, when the gauge is between 1/8 and 1/4 tank and she takes about 3.5 or so gallons, and that's with the bike on the kickstand so there's probably more room in there, but seems accurate - or at least, consistent.

I'd estimate the 0-60 time on this bike is about 7-8 seconds. I've read 5.75 seconds, but it's not near that fast, imo (my car is that fast, and this bike is not nearly as fast as my car). I think my wife's V6 Sonata would probably give it a run for it's money :)
 

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Its good for a quick estimate, but your odometer will be much more reliable in telling you how much is really in there.

Last months cycle world had an article on "Best Beginner Bikes" the 250r was in there, and they called it 7.4s 0-60, and 15.5ish quarter mile.
 

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Mine is accurate. When I first gotten the bike, I listened to some bozos here saying when it's on "E", you have about 50 miles...well, first ride out and it was showing E on mine so I thought I will last...wrong...she started loosing power, puttering etc...so Ipulled over to the next gas station, filled her up and she ran fine after that.
 
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