Fuel/Speedo gauge fix

[ninja250]

I think I came up with an idea to fix the speedometers and fuel gauges incorrectly reading with no extra hardware.

I have been working with the gauges a lot lately and notice you can pull the needles off your stock gauges. You have to put them back on correctly too, which requires you to know where to put them and how!

If you set your bike to 1500 rpm idle speed and need to remove the rpm needle (to get behind the RPM gauge face) you will have to put it back on somehow.
It's a spring loaded mechanism so you can't really do it accurately. The trick is to turn the bike back on, warm it up and let it idle at 1500rpm, then install the needle with the gauge face open. hehe

So, to fix your fuel gauge that is reading incorrectly, go fill your bike up with fuel, pull your gauge case apart and pull the needle off and set it to full. (or alternatively, you can go empty your bike and set the needle at or below empty.

Now I'm wondering:
If I use my iphone to GPS the speed on the motorcycle, I can plug the needle in to the speedometer at the exact speed the GPS is reading. This would require me to be moving on the bike and plug the needle in to the gauge at the same speed as the GPS reads.

But, it would fix my incorrectly reading speedometer. (In theory)
Also, it would surely fix an incorrectly reading fuel gauge,
and in turn, the RPM gauge.

enjoy
I sold my stock gauges already or this would be a picture/video DIY.

[ninja250]

In other words..

Those of you who have gauges that read incorrectly can calibrate your gauge needles with a bit of mechanical apt.

It would appear the gauges simply weren't calibrated as close as they could have been from the factory.

[Alex]

The problem isn't just that they are incorrect at a single speed, or level. The problem is that as they move, the differences they are showing are different than the actual differences.

In other words, if you somehow are able to reset the speedometer needle to point to 60 mph when the gps says exactly 60 mph, the speedometer will still be wrong at 30 mph and at 90 mph. The difference between actual and indicated isn't always the same # of mph, it's much closer to a percentage difference.

Same with the fuel gauge. If you have a gauge that doesn't read full, yet reads empty early, and you reset the needle to read full, it might never make its way down to empty.

[k-os]

The amount that the gauges are off, as Alex is saying, is exponential. The faster you go the more they read incorrectly. If you calibrate it at 60, it will still read incorrectly at other speeds.

[ninja250]

I've noticed this. at 100 mph it's 10 percent off while at 50mph it's 5% off.
I'd imagine you could calibrate it to be closer at all speeds then using the percentage to your advantage. (slighter over at low speed slighter under at high to get it closer on all planes)

The fuel gauge this would definitely work. HB has his like this right now and needs to use my trick to fix it. I hear people complain their fuel gauge indicates wrong all the time. This WILL fix it. The needle has to be calibrated.

I would calibrate to the empty tank to be honest. This would get you indicating a correct "E"
How full it is from there doesn't matter as long as you know it's gonna be empty when it says E.

[Alex]

No, it won't fix all fuel gauge problems either. Some folks have found the problem to be the sensor on the tank float. So if the gauge is reading empty when it has 2 gallons in it, if you tweak the gauge to read 1/3 of a tank with 2 gallons in it, it will still read 1/3 of a tank when the tank is out of gas. The sensor will not read any lower, and therefore the gauge won't read any lower.

It's like fixing a broken clock by seeing what time it is right now and moving the hands into position. And yes, that clock will be exactly correct twice a day.

[ninja250]

Didn't say it would fix all problems, just something you can try

[Kevin2109]

The fuel actually can be fixed, because thats how mine is right now! it reads half full at empty because when I put the needle back on wrong

[CZroe]

It's really more of an adjustment. I'd prefer my speedometer to read more accurately at 55-60MPH than 20MPH because more important speed limits are around that range.

As for the fuel gauge, I've found more fuel in my tank with a lower reading than I have with a higher one, so I don't think we can fix that by calibrating for empty. IOW, I've been running on fumes with barely under an eighth indicated remaining and then I've gotten down to or even below E and found MORE fuel was in the tank than the time it indicated that I still had an eighth! Usually a half-gallon.