Wildguzzi.com
General Category => General Discussion => Topic started by: antmanbee on May 24, 2020, 09:25:29 AM
-
On a Breva 750 is the low fuel light supposed to come on when you fist turn on the key as a check?
If not, does this mean the bulb is burned out or are there other possibilities? The light has never worked on this bike since I purchased it used.
The circuit outside of the dash looks simple. It is just a thermistor in the tank with a line in and out from the dash.
I have found no information on what goes on inside the dash.
-
On a Breva 750 is the low fuel light supposed to come on when you fist turn on the key as a check?
If not, does this mean the bulb is burned out or are there other possibilities? The light has never worked on this bike since I purchased it used.
The circuit outside of the dash looks simple. It is just a thermistor in the tank with a line in and out from the dash.
I have found no information on what goes on inside the dash.
No 'test' function.
The thermistor is about 1200 ohm at room temp.
Nothing in the dash but a bulb. Short out the thermistor and the bulb should light.
-
Thanks Wayne.
I have some of these thermistors to use if the Breva one tests bad. It is 2K ohm at room temp.
Digi-Key Part Number 480-3340-ND
Manufacturer Honeywell Sensing and Productivity Solutions
Manufacturer Part Number 135-202FAG-J01
Description THERMISTOR NTC 2KOHM 3468K DO35
-
Well, I'm thinking:
I suspect that you need a lower resistance, to generate the heat, that starts the process where it self heats and lights the bulb.
I can't find a single bit of info on the wattage of that thermistor. That looks like about 1/4 watt. The one in the tank is large, closer to 1 watt, to pass that bulb current.
The one in the tank is enclosed in a shield, in case something goes wrong in the gasoline, it is less likely to be a safety issue.
Have you tested the bulb?
-
No I have not tested anything yet. I am going out to ride it now but I will probably pull it apart enough to test it tomorrow or Tuesday.
That is the thermistor that someone in the Ducati forum used to fix his low fuel light issue.
-
See post #30 in this Ducati thread for how he did it.
https://www.ducati.ms/threads/ran-out-of-fuel-twice-no-fuel-light.132039/page-2 (https://www.ducati.ms/threads/ran-out-of-fuel-twice-no-fuel-light.132039/page-2)
-
Well, I'm thinking:
I suspect that you need a lower resistance, to generate the heat, that starts the process where it self heats and lights the bulb.
I can't find a single bit of info on the wattage of that thermistor. That looks like about 1/4 watt. The one in the tank is large, closer to 1 watt, to pass that bulb current.
The one in the tank is enclosed in a shield, in case something goes wrong in the gasoline, it is less likely to be a safety issue.
Have you tested the bulb?
The sensor Wayne mentioned is made by Panasonic. the thermistor is enclosed in a metal can with a very fine slot to allow the fuel In/Out, I was able to purchase a couple, one I used on an early Triumph the other I used on a Guzzi, I will try to find the part No but I wouldn't hold out much hope of finding one to purchase.
Typically they either work or not, Measure the resistance with your meter or short the wire to chassis to test the lamp. They would often get burnt out by mixing the plug with the one for an electric petcock.
LED lamps do not draw enough current to make the thermistor heat up, I have several times replaced the dash lamp with an LED but retained one of the incandescent lamps out of sight in parallel.
-
On a Breva 750 is the low fuel light supposed to come on when you fist turn on the key as a check?
.......
I believe so. On the V7, all the dash lights cycle when the ignition is first turned on. I shouldn't think the Breva would be different, same ECU as the early V7, though the dash is physically different.
-
I looked at the wiring diagram for an early V7 Classic and it is very close to the Breva but not the same.
To the thermistor is one wire from the dash and the other wire off the thermistor goes to ground.
On the Breva both wires off the thermistor go to the dash. I assume 1 wire is for ground and it is grounded through the dash.
But no telling without a dash diagram.
Big block Guzzis like V11, EV, Jackal, I am pretty sure it is like Wayne said and has not test function.
But is there anyone with a Breva 750 that can confirm that if the key is turned on and the dash does it's sweep that the fuel light comes on briefly?
-
On my Breva it comes on "occasionally ".
-
Just spoke with Gonzo. On his Breva, the low fuel light does NOT cycle on initial ignition. Although it does come on sometimes, then fade out without fuel being low - and that's on an 8,000 km bike.
-
On my Breva it comes on "occasionally ".
I don't understand. Do you mean in general use while riding it comes on occasionally?
What I want to know is when you switch on the key and the dash needles sweep and the dash lights come on, does the fuel light always come on briefly too?
-
Just spoke with Gonzo. On his Breva, the low fuel light does NOT cycle on initial ignition. Although it does come on sometimes, then fade out without fuel being low - and that's on an 8,000 km bike.
Thanks, that's kind of strange to have that inconsistency.
-
Here is a replacement for the thermistor in the V11 Fuel tank, Panasonic part No is ERTLG12N7
Oops this is only for a dash with dedicated light bulbs, not for an electronic dash with stepper motor speedo etc
http://industrial.panasonic.com/lecs/www-data/pdf/AUD0000/AUD0000CE2.pdf
I tried contacting Panasonic without success but found them on a Chinese site N Gate for $15, I ordered a pair, they took
about 2 months to arrive, I think they were shipped by boat.
It's not a direct replacement you will have to adapt the holder somewhat but for $15 instead of $150+
Its a direct replacement for the one in my friends old Triumph Tiger.
Here we go with the data sheet
https://static6.arrow.com/aropdfconversion/599d112d4eefad38687211b895992cc0102dc8b9/aud0000ce2.pdf
I wouldn't be at all surprised if you are unable to find these to purchase, I had enough trouble 3 years ago, I suspect someone is trying to corner the market, many automobiles use this sensor.
-
http://www.thisoldtractor.com/guzzi007/schematics/2004_750_Breva.gif
The Breva schematic shows an in tank pump and sensor (10), its anybodies guess what this is, at first I thought it would have a float switch for the electronic dash but I have been wrong before.
They do use the same symbology for (10) and (45) which would be a thermistor for sure.
If it is a thermistor I don't think it would be possible to mix up the connector and burn it out as happened so often on the Californias.
I agree with Wayne, if its a thermistor it would need to be < 1k to start heating up and it should be enclosed like the Panasonic, a thermistor will glow white hot if its fed 12 Volts and not covered in fuel.
https://static6.arrow.com/aropdfconversion/599d112d4eefad38687211b895992cc0102dc8b9/aud0000ce2.pdf
-
I found a picture of the Breva 750 pump assembly and the sensor looks like a thermistor in a can which is typical for the submersible pump assemblies.
The blue and white wires go back to the dash.
(https://i.ibb.co/Jcmn3vF/Breva-750-fuel-pump.jpg) (https://ibb.co/Jcmn3vF)
-
Well I have 10.9V across the two wires that go int the dash. If I short them I still have no low fuel light.
I have 2.5K ohms across the two wires going to the thermistor which is submerged in fuel.
-
Do the other lights cycle when you turn the key On?
The dash doesn't have replaceable lamps, just LEDs soldered to the board.
-
Yes all the other functions and lights of the dash work.
There is one other thing odd and this may be normal but I have no way of knowing as I have only experience with this one Breva,
but the hazard light switch on the dash is lit up all the time while the bike is running or if the key is in the on position.
The hazard switch/light will flash on and off if turned on.
Is this normal? It seems to me it would be better not lit up as the default and only flash when turned on.
-
Does not come on with the key that I recall.
(https://i.ibb.co/mqbmFc4/IMG-0416.jpg) (https://ibb.co/mqbmFc4)
-
Does not come on with the key that I recall.
(https://i.ibb.co/mqbmFc4/IMG-0416.jpg) (https://ibb.co/mqbmFc4)
Wayne,
Are you referring to the Fuel light or the Flasher warning light?
-
Wayne,
Are you referring to the Fuel light or the Flasher warning light?
Sorry, fuel light only came on with low fuel.
I'm not certain on the flasher light.
-
On my '08 Breva the fuel light only comes on when the fuel is low, not on startup. The red hazard light is on the whole time the ignition is on.
-
I wonder if there is a delay on the low fuel light, you would expect it to come on if the sensor wires are shorted together.
I have a dash here but I need to get a cable so I can connect to it.
-
With having shorted the 2 wires to the dash and no light while shorted, there is my problem.
So the question for me is, will it be worth the risk of dash disassembly of a otherwise fully functioning dash to possibly fix the light.
From reading more from the Ducati thread it looks like there is a 116 ohm resistor in series with the thermistor. So there are other possible faults besides the LED.
This info is from the Ducati thread,
First how it works : The thermistor is a device which changes resistance with temperature, with resistance dropping as temperature increases. As it is a resistor, it generates heat, which in turn reduces its resistance, generating more heat etc etc... When the thermistor is inside the fuel, the heat dissipation to the fluid is high enough that it exceeds the heat being generated by the thermistor and hence its temperature is stabilized at a certain level. However, when the fuel is low, and the thermistor is in air, the heat dissipation rate decreases, such that the thermistor starts to increase temperature. The fuel light works by putting the thermistor is series with a set resistance in order to deliver a designed current to the dash when the thermistor resistance ( as dictated by its temperature) rises above a defined value.
Measurements : Using a potentiometer in place of the thermistor it was possible to deduce that the light will come on when the thermistor resistance is below 160 ohms. By measuring the voltage drop over the potentiometer at various values it was possible to deduce that on the bike the thermistor is in series with a resistor of 116 ohms. What has happened to my stock sensor was that it was still generally working, but did not drop resistance far enough, hence the light did not come on.
Challenge : need to find thermistor which will provide the correct characteristics : resistance in fuel > 160 ohms, resistance in air < 160 ohms, but beyond this must have high resistance in fuel to avoid big constant current draw, and must be such that it doesn't go unstable ( heat up excessively) when exposed to air. Thermistors are defined by their B value, but generally also share their dissipation constant in air, and the current they will accept. Using this it was possible to build a system model, calculating resistance and hence heat generation, as well as the heat dissipation rate when in or out of the fuel. Of course, it is also somewhat important to make sure that the thermistor in air does not exceed the fuel auto-ignite temp, or the max temp permitted by the thermistor.
Result : using published properties, and knowing something of the application, I was able to select the Honeywell 135-202FAG-J01 with B value 3468K and dissipation in air of 2.5mW/degC. The nice part of this thermistor is that it is glass encased, and hence not affected by the fuel as I suspect the stock ones are. Cost was a whopping $1.47 a piece.
Testing : Bench testing was completed with 12v and a series resistor of 116 ohms to confirm that the thermistor selected responds as expected, and then I fitted it to the bike ( but not in the tank) and confirmed function by testing in and out of fluid. The fuel light worked as expected. As the worst case for the thermistor is when it is dry, I ran the thermistor in air for 24 hours constantly, and all seemed fine. However, this is as far as I got and never fitted the thermistor to the bike. I will when my light fails next time. To fit it, I'll need to dismantle the stock sensor, and fit the new thermistor in place of the old one.
BTW - note that the thermistor is mounted inside a can which has only small holes in it, such that the thermistor response is slowed and the light doesn't go on/ constantly when the fuel level is near the switch level.
So that's the status - the design is done, but not yet tested. Try it at your own risk !
-
The other models that I owned, the EV and the Centauro, that use that same thermistor, did NOT have a resistor also. It was a simple thermistor and bulb, nothing else.
You shorted the wires, and the bulb did not light. Bad bulb or wiring, right?
Sounds like you are itching to replace the thermistor anyway, even though the bulb does not work.
-
The small holes in the can are not to damp the fluid, If the sensor receives full 12 Volts in air the it can get white hot and fuse, any flame is cooled passing through the tiny holes so its contained inside the capsule. That's why you cannot use a bare thermistor.
If the light doesn't go when you short the wires out do you think a new sensor will fix it?
The dash I have is not screwed together, the light is a surface mount LED, when I find another ribbon cable I will check it out.
I think the 2.5k resistance you measured may be ok although I expected it to be lower.
BTW, is the text on your screen extra wide, (on my Mac it disappears off to the side) I think its caused by the reference in the 3rd post setting the text width
-
The other models that I owned, the EV and the Centauro, that use that same thermistor, did NOT have a resistor also. It was a simple thermistor and bulb, nothing else.
You shorted the wires, and the bulb did not light. Bad bulb or wiring, right?
Sounds like you are itching to replace the thermistor anyway, even though the bulb does not work.
I am not itching to replace anything. I wish I had the luck to only have a bad thermistor because it looks relatively easy and cheap to repair.
I was including all the pertinent information I had found about the thermistor repair because I think that a thermistor failure is probably more common.
The little 'thermistor in a can' seems to be on most of the internal pump/filter assemblies from the Italian manufacturers.
I have seen it on my Griso and CalVin too, and in many photos of pump assemblies while researching.
I included the information about the extra resistor in series because the Ducati has an electronic dash like on most late model Guzzis and I thought it would be similar.
I would much prefer if all my newer bikes had the gauge and warning light set up of the EV or Centauro.
I hate the electronic dash with it's integration of key immobilizers, parasitic drain, key codes and links to the ECU.
-
The small holes in the can are not to damp the fluid, If the sensor receives full 12 Volts in air the it can get white hot and fuse, any flame is cooled passing through the tiny holes so its contained inside the capsule. That's why you cannot use a bare thermistor.
If the light doesn't go when you short the wires out do you think a new sensor will fix it?
The dash I have is not screwed together, the light is a surface mount LED, when I find another ribbon cable I will check it out.
I think the 2.5k resistance you measured may be ok although I expected it to be lower.
BTW, is the text on your screen extra wide, (on my Mac it disappears off to the side) I think its caused by the reference in the 3rd post setting the text width
I don't think a new thermistor will fix it. It seems to me that shorting the wires to the dash should turn on the light.
I would think that the value of 2.5K would not matter as long as the resistance drops down low enough when the thermistor heats up when exposed to air.
The new thermistors I have that are rated as 2K test about 1.65K.
The text wrap in post 3 from the hyperlink to the thermistor is what is causing the extra wide screen. I will remove the link and just put the part number in the post instead.
-
I am not itching to replace anything. I wish I had the luck to only have a bad thermistor because it looks relatively easy and cheap to repair.
......
I would much prefer if all my newer bikes had the gauge and warning light set up of the EV or Centauro.
I hate the electronic dash with it's integration of key immobilizers, parasitic drain, key codes and links to the ECU.
On the early California's and a few others, with the external fuel pump, the fuel solenoid and fuel sensor plug were identical. It was easy to inadvertently mix them up. One had red paint on it, but still, they got crossed often. That would apply 12 volt solenoid power to the thermistor and it would of course kill it. I have heard of a few of the sensors leaking too. But I can't say I have ever heard of a sensor just failing. They are pretty simple and reliable.
Is your dash not like that photo I posted? I didn't know they had anything more complex on the 750 Breva.
-
I don't think a new thermistor will fix it. It seems to me that shorting the wires to the dash should turn on the light.
I would think that the value of 2.5K would not matter as long as the resistance drops down low enough when the thermistor heats up when exposed to air.
The new thermistors I have that are rated as 2K test about 1.65K.
As long as the resistance is low enough to allow it to self heat. And of course low enough when hot to light the bulb.
I suspect that in cold weather, a 2k thermistor (which would be much more then 2k when cold) would have a hard time self heating to start the 'cycle'. I've always bee surprised that the 1.2k factory ones can get hot enough to work in cold weather.
Have you tried to get into the dash? Have you measured the voltage across the sensor with the key on? If no voltage, the issue is in the dash for sure.
-
As Roy suggested, I tested the current across the 2 wires to the dash.
This is getting interesting and confusing now for me.
When I tested the current the fuel light on the dash came on.
The current is 94mA. It takes about 5 seconds for the light to come on after the amp meter is put across the 2 wires.
A dead short still will not turn on the light.
(https://i.ibb.co/QQQdfGY/IMG-1718.jpg) (https://ibb.co/QQQdfGY)
-
As Roy suggested, I tested the current across the 2 wires to the dash.
This is getting interesting and confusing now for me.
When I tested the current the fuel light on the dash came on.
The current is 94mA. It takes about 5 seconds for the light to come on after the amp meter is put across the 2 wires.
A dead short still will not turn on the light.
(https://i.ibb.co/QQQdfGY/IMG-1718.jpg) (https://ibb.co/QQQdfGY)
The ammeter lights the light, yet a short does not?
:coffee:
94ma is pretty much the current for a #74 bulb, like used in the other models.
-
Yes the ammeter lights the light.
I put a 162 ohm resistor across and it lights the light.
A 330 ohm resistor does not light the light.
So maybe the thermistor is bad and it just does not drop down to the proper resistance when heated up. (out of contact with the fuel)
-
Another test with my new thermistor which is the one from the Ducati fix.
I had to leave it plugged in to the 2 wires to the dash for a minute or more and then it lit the dash light.
I had tried this before but only left it plugged in for maybe a half a minute or so and it did not lite. It felt warm but apparently it was not warm enough. I jumped to the wrong conclusion.
So it looks like my fix is to follow the Ducati thread fix.
People over there have had the fix working for several years now.
Wayne, you were right, I guess I was itching to replace the thermistor.
-
Thats great news.
I can't understand why your ammeter would make the light go but a short won't, pretty much the same thing, perhaps it has a cut-out for too much current.
I went and got the ribbon cable from a computer. I'm busy cutting it down to just 30 wires so I can test the dash and see what it does,
This is the sensor shown in your picture, I put one in a mate's Triumph Tiger, I think they are used in many cars as well
https://static6.arrow.com/aropdfconversion/599d112d4eefad38687211b895992cc0102dc8b9/aud0000ce2.pdf
I approached Panasonic about these last time and they denied all knowledge about them, I was able to find them on a Chinese website ----gate is all I can remember, I think $15 each
Any chance you could empty your tank to give the existing sensor a good test, 2.5 K sounds high but perhaps being in a can allows it to eventually take off, they do take a while.
I see you fixed the screen width, thanks for that.
-
I will empty the tank this coming weekend hopefully.
The sensor you linked would probably work. It does look a bit larger but that would probably not be an issue.
I think the key issue is what is the fully heated resistance. I think it probably needs to be in the range of 100-160 ohms. That specification is hard to come by.
I have the glass coated thermistors that I referenced from Digi-key in an earlier post that was also used to fix the Ducati.
If you look at post #41 and #42 in the Ducati thread there are some good pictures and description of removing the thermistor from the can and replacing it.
I will replace the fuel filter while the assembly is out of the bike and maybe the submersible hose too.
I got the bike with 23K miles and it now has 27K. I don't know if the filter has ever been replaced.
Thanks Roy and Wayne and everyone else!
-
I believe so. On the V7, all the dash lights cycle when the ignition is first turned on. I shouldn't think the Breva would be different, same ECU as the early V7, though the dash is physically different.
Mine only lights upm at 160-170 miles, with about 5 lits left.
-
It should be fixed now. I just need to run it low enough on gas to see if it works.
The new thermistor worked before assembly by just putting it across the 2 wires to the dash and waiting a minute for it to heat up and the resistance to drop.
The failed thermistor,
(https://i.ibb.co/9qCHDfg/IMG-1728.jpg) (https://ibb.co/9qCHDfg)
I carefully pried open the folder over lip on the can and de- soldered the tip of the thermistor from the other end,
(https://i.ibb.co/n797qH6/IMG-1729.jpg) (https://ibb.co/n797qH6)
Soldered in the new thermistor,
(https://i.ibb.co/wJTz9tS/IMG-1731.jpg) (https://ibb.co/wJTz9tS)
The empty can with a tiny hole drilled in the end to accept the nre thermistor and solder,
(https://i.ibb.co/cD2fmh5/IMG-1730.jpg) (https://ibb.co/cD2fmh5)
The completed can with the lip bent back over with pliers and the other end of the thermistor soldered in, now ready to be attached to the pump assembly,
(https://i.ibb.co/NT4hVft/IMG-1734.jpg) (https://ibb.co/NT4hVft)
Pump assembly ready to go back into the tank,
(https://i.ibb.co/jVk1VZk/IMG-1735.jpg) (https://ibb.co/jVk1VZk)
-
One thing to be aware of, regular wire is not sealed from end to end gas could migrate up the cable between the strands. Hopefully you haven't compromised the tank seal where the cable enters the bottom of tank, just check once you have the tank full.
-
One thing to be aware of, regular wire is not sealed from end to end gas could migrate up the cable between the strands. Hopefully you haven't compromised the tank seal where the cable enters the bottom of tank, just check once you have the tank full.
I don't think this will be an issue. The thermistor/can assembly has it's own plug that plugs into the harness that comes through the fuel pump mounting plate.
There should be no compromising of that harness.
-
Went out for a spin.
The fuel level in the tank was low.
I was proceeding without any extra fuel in a can.
The light remained off.
I didn't know how far I would have to go to get the light to come on if at all.
Only just a mile down the road the light started to flicker.
After another mile it was on steady.
Pulled into a gas station and filled it up.
3.17 gallons.
Light off again.
Yeah! It works.
-
So far, so good.
-
Congratulations on a successful project
I was curious so I looked your sensor up, although they don't actually spell it out its obvious they make sensors for measuring fuel.
https://sensing.honeywell.com/honeywell-sensing-temperature-sensors-line-guide-009033-4-en.pdf look at 135 series on page 6
Here is another thermistor that Guzzi have been using for engine temperature, Air temperature etc
https://www.digikey.ca/en/products/detail/vishay-bc-components/NTCLE203E3302SB0/2601763?s=N4IgTCBcDaIHIBUDCAZAomADAZjd7mYAygEKYgC6AvkA
The one they use is 3000 Ohms at 25 degrees Celsius
NTCLE203E3302SB on page 3 you will see the Ohms at different temperatures lines up with the Air and Oil temperature sensors in the guzzi manuals
I'm sure Honeywell have the same thing.
-
I was looking for a data sheet that gave the resistance chart like the one you linked for the vishay thermistor. I could not find one.
The chart is very useful but the bit of missing information that is still needed to determine if the thermistor will work is what temperature/resistance value is it with voltage across it when out of the fuel and in the air?
To work I know 320 ohms is too high and 0 ohms is too low. So the (out of the fuel/in the air) resistance needs to bee somewhere in between. I know 162 ohms works but I don't know what the actual range is
Testing with a potentiometer could determine this range.
I found some more of the glass coated thermistors that look to be the same on ebay for really cheap.
Search, 10pcs NTC Thermistor 2K ohm 1% B 3800 Diode Type Glass Encapsulated Thermistor
I didn't want to put in the super long hyperlink and have the text wrap issue again.
-
I was looking for a data sheet that gave the resistance chart like the one you linked for the vishay thermistor. I could not find one.
The chart is very useful but the bit of missing information that is still needed to determine if the thermistor will work is what temperature/resistance value is it with voltage across it when out of the fuel and in the air?
To work I know 320 ohms is too high and 0 ohms is too low. So the (out of the fuel/in the air) resistance needs to bee somewhere in between. I know 162 ohms works but I don't know what the actual range is
Testing with a potentiometer could determine this range.
I found some more of the glass coated thermistors that look to be the same on ebay for really cheap.
Search, 10pcs NTC Thermistor 2K ohm 1% B 3800 Diode Type Glass Encapsulated Thermistor
I didn't want to put in the super long hyperlink and have the text wrap issue again.
Most thermistor specs include a chart to give the thermistor value at various temperatures. I put a thermistor on the microprocessor based battery charger I just designed and the thermistor included a chart with the resistance value at every 5C degree step. So it was easy in my software to determine the battery temperature within 5C. Then interpolate the actually temperature between each step. I was surprised at how accurate it really was.
In this case, since it is self heating, the length of the leads and a lot of such things will determine how fast the heat can escape the thermistor, so it will determine how hot it gets and thus the final resistance in open air. I'm still surprised that a 2k ohm thermistor can self heat enough to start the 'cycle'. That is only 0.072 watts at 12 volts. Not a lot. I still wonder if it will work in cold weather when the thermistor resistance is even higher.
You mentioned earlier that the light 'flickered'. On the EV style setup, the thermistor slowly heats up and passes more current to the bulb, as the thermistor slowly heats more and more. It is a very simple bulb and thermistor design. Eventually the bulb starts to glow and get brighter and brighter. It takes a few seconds to come on. Does the bulb on yours actually flicker on and off rapidly? If so, that would mean a more complicated design. Not sure why they would do that, other than to make the bulb light brighter. The EV type bulb never gets real bright.
You can use https://tinyurl.com/ or such to generate a short URL to add to a post.
-
Just an FYI, a low fuel sensor from a 67-73 Mustang / Cougar Low Fuel Warning SENSOR - Fuel Sender Mounted $16.75(Ebay) works!! Thought it was a fail until I was referred to this post and discovered I needed to leave the ignition on for longer than a minute..
-
Necro thread
My B750 ran out of gas last week without the low fuel light ever coming on. It usually comes on with 1.5 (US) gal remaining.
-
Necro thread
My B750 ran out of gas last week without the low fuel light ever coming on. It usually comes on with 1.5 (US) gal remaining.
I know how many miles mine will do before it comes on. It has never failed me yet; howver, if it went say 10 miles past where it shou8ld be on I would be most definitely stopping and give the tank a slosh. If it was sounding low I don't think I would risk it. I can assure you, the Breva might not be as heavy as a big block but pushing it a couple of kms up a slight rise is something I don't want to repeat.
-
Just spoke with Gonzo. On his Breva, the low fuel light does NOT cycle on initial ignition. Although it does come on sometimes, then fade out without fuel being low - and that's on an 8,000 km bike.
On my 2004 Breva 750 with ~22k miles, the fuel light is fairly accurate. As in, when the fuel level is low, it comes up. When I fill it up, the light goes out.
Basically, the light does a good enough job of warning me to fill the gas :thumb: