[How to Tutorial] Alternative Gas Fuel Level Sender/Sensor Gauges for Carby GT GTR Hyosung
- This topic has 11 replies, 4 voices, and was last updated 5 months, 1 week ago by
.
-
Posts
-
-
.bbpress-topic img {
This topic for Gas Fuel Tank Level Sensor/Sender replacement applies only to
CARB VERSIONS of GT Naked & GTR Hyosung Models.
We’re going to take a look at various fuel sensors (level senders) that can be used inside your tank.The carby ones are no longer made. The world has moved on to EFI systems, it is what it is.
To preserve our carby bikes, we’ll slowly add some topics like these to use parts from Cars, Trucks, etc.
I’ll avoid mentioning other bikes — car/truck parts are more widespread and easier to source!Applies strictly to these bikes:
GT125 Naked & GT125R GT250 + GT250R GT650 + GT650R All carb models (2001–2021) Carby only Carby only
Sensor #1 – Toyota Hilux
Part Numbers: 83320-80357, 83320-39516
This one has a very long arm, but it fits inside the GT tank with some modding.
A rider from Portugal confirmed it works fine.⚠️ Do NOT cut your main bike harness!
Simply replace the sender’s connector with a common 2-pin 2.8mm connector used in cars.
- TOYOTA HILUX 2.4L Diesel (1997–2001)
- TOYOTA HILUX 2.8L Diesel (1997–2006)
Sensor #2 – Toyota Hilux (different style)
Part Number: 83320-39405
Similar to the first one, same base and gasket, float arm slightly different.
Replace the connector and extend the cable if needed.
Fits Toyota models: LN55, RN50, YN55, RN55, LN85, LN80, YN85, RN85⚠️ Note: Both Toyota sensors may not read Hyosung levels accurately.
Always ask the seller for the Ohms range (Full → Empty).
Avoid shady sellers — stick to Amazon Prime or Toyota dealers.
Fuel Tank Sensor Facts (GT125R, GT250, GT650 Carby)
- Fuel Low = 100+ Ohms
- Fuel High = ~30 Ohms
Wire colour = Yellow with Black stripe (tank → dash)
Q&A for newer GT125R (2012–2021)
Q: My 2016 GT125R fuel light flashes even when fine? A: The dash is fussy! Clean the connectors, check continuity, test the sender.
Sometimes it takes 10 mins to stabilise the reading.
💭 This guide will be refined over time. Share it if useful!
Extra Notes
- Bolts: M5 x 16mm stainless steel recommended
- Alternative vehicles with similar senders: Isuzu TFR, Vauxhall Brava, Isuzu Rodeo, Opel Campo, etc.
Ride safe & don’t get stranded ⛽
Disclaimer: This guide is for information only. Consult a competent mechanic if unsure.
max-width: 100%;
height: auto;
border-radius: 6px;
}
.bbpress-topic table {
width: 100%;
border-collapse: collapse;
margin: 1em 0;
}
.bbpress-topic td {
vertical-align: top;
padding: 8px;
}
.bbpress-topic hr {
border: 0;
border-top: 1px solid #444;
margin: 1.5em 0;
}
-
-
Useful info there Marcel.
Thank you my fellow man 😉
I haven’t forgotten about EFi , was thinking of finding ways to replace their fuel senders and throttle cables and what not. Sender from a car is possible , i don’t see why not but cables may be from a bike instead. I will do further studies and testing at my end (unless i have someone to test stuff for me haha)Hope you are good!
-
3 questions. I think. Block off the sending unit hole in the tank, go with old school petcock with off, on, and reserve( no standpipe for reserve? no vacuum bullshite, no gauge level.
The fuel pump is gravity-fed. Is it needed due to the orientation of the carbs float bowls or a v twin-specific issue( for the most part I have only dealt with singles or parallel twin carbs)? I have a new one either way.
Question 3? Somewhere on this forum, I saw a post with pics of how to eliminate the air valve thingy. Should the line coming from the base of the rear cylinder have a check valve installed for crankcase ventilation? I might have missed something being a USA citizen (joke).
I’ll expect a reply just as I wake up at 3 am to watch Moto GP live from Assen.-
I answered my own questions: The tank outlet is level or just above the carb inlet. (So the pump is needed),( head pressure and such).
The petcock is situated at the rear middle of the tank. ( so a manual petcock would have to be remote to be accessible ).
And finally just block the pump hole and watch the odometer for range. -
-
-
-
tutorial for egr block off is in tutorials section even for the 650cc is the same principal
tank – how will you know you have low fuel ? the bike behaves worse when fuel level is too low in tank (as quoted from service book)
the vacuum taps are okay , they work nicely with vacuum pump – i tried bypassing, the bikes hate it. so respect to korea for leaving the pump on the frame for high speed runs
-
I may be wrong here: Most cars/trucks I have seen ,the sender unit mounts from the top of the tank down vs a motorcycle. Would that warrant swapping the wires to correct the ohms reading? Also, at least here in the US the first part numbers 34810 match a Suzuki side kick. It all seems to be reversed as far as the photos go.
-
Some unknown sendors will be reversed saying EMTPY on the dash when the tank is actually full, i have experienced this myself. So Hyosung seems to be dead set on their dashboards making sure empty starts at at the base of the tank, as the float goes , the bars on the dash correspond to it.
either way based on my extensive tests of OEM hyosung senders, the ohms in this topic must match (or close to ) whichever sensor you would like to affix to the tank
Hope this helps
Toyota Hilux is common in asian countries where Hyosung is also present as alternative senders.
-
I bought a new sender from a car/truck ; although the mount flange is the same pattern and float arm would need to be modified it works bassakwards as far as resistance goes. Which is what I feared would happen as most cars/trucks level senders are mounted from the top of the tank unlike , I assume most bikes.
I would go with an old-school manual Petcock if the location was reachable. I don’t remember from whom I purchased the thing or what model it fit.
I was probably shopping while drinking and didn’t go from your list of recommendations. Also while drinking : The”SWAP THE WIRES “comment of mine , WHAT AN IDIOT. I’ve got a sender that I bought accidentally with the oval base which I guess is supposed to fit the injected models if someone wants it, just pay for shipping ( I’m in the US) the readings on that are 8.6 ohms empty 97.2 ohms full so this may not be in order either.
Lest I word on more; I think I’ll just seal the broken sender back in the tank and move on to other issues. Thank you for your help.
-
-
For those wondering. CARB bikes with first gen green dashboards (gv/gt650, gt250 / two connectors to the display) have different readings. It’s actually 100 oms – full and 20 – empty. The next gen green dashboard (with a single connector from the board to the display) is apposite. I was surprised recently when was working with dashboards and switching them over. There’s a way to modify the stock 1st gen fuel level sensor. By inverting the position of the float arm to the other side. You’ll need a new steel rod though to shape the new float arm. Works well.
-
- You cannot reply to this topic.
- This topic has 11 replies, 4 voices, and was last updated 5 months, 1 week ago by .
-
Posts
-
-
This topic for Gas Fuel Tank Level Sensor/Sender replacement applies only to
CARB VERSIONS of GT Naked & GTR Hyosung Models.
We’re going to take a look at various fuel sensors (level senders) that can be used inside your tank.The carby ones are no longer made. The world has moved on to EFI systems, it is what it is.
To preserve our carby bikes, we’ll slowly add some topics like these to use parts from Cars, Trucks, etc.
I’ll avoid mentioning other bikes — car/truck parts are more widespread and easier to source!Applies strictly to these bikes:
GT125 Naked & GT125R GT250 + GT250R GT650 + GT650R All carb models (2001–2021) Carby only Carby only
Sensor #1 – Toyota Hilux
Part Numbers: 83320-80357, 83320-39516
This one has a very long arm, but it fits inside the GT tank with some modding.
A rider from Portugal confirmed it works fine.⚠️ Do NOT cut your main bike harness!
Simply replace the sender’s connector with a common 2-pin 2.8mm connector used in cars.
- TOYOTA HILUX 2.4L Diesel (1997–2001)
- TOYOTA HILUX 2.8L Diesel (1997–2006)
Sensor #2 – Toyota Hilux (different style)
Part Number: 83320-39405
Similar to the first one, same base and gasket, float arm slightly different.
Replace the connector and extend the cable if needed.
Fits Toyota models: LN55, RN50, YN55, RN55, LN85, LN80, YN85, RN85⚠️ Note: Both Toyota sensors may not read Hyosung levels accurately.
Always ask the seller for the Ohms range (Full → Empty).
Avoid shady sellers — stick to Amazon Prime or Toyota dealers.
Fuel Tank Sensor Facts (GT125R, GT250, GT650 Carby)
- Fuel Low = 100+ Ohms
- Fuel High = ~30 Ohms
Wire colour = Yellow with Black stripe (tank → dash)
Q&A for newer GT125R (2012–2021)
Q: My 2016 GT125R fuel light flashes even when fine? A: The dash is fussy! Clean the connectors, check continuity, test the sender.
Sometimes it takes 10 mins to stabilise the reading.
💭 This guide will be refined over time. Share it if useful!
Extra Notes
- Bolts: M5 x 16mm stainless steel recommended
- Alternative vehicles with similar senders: Isuzu TFR, Vauxhall Brava, Isuzu Rodeo, Opel Campo, etc.
Ride safe & don’t get stranded ⛽
Disclaimer: This guide is for information only. Consult a competent mechanic if unsure.
-
-
Useful info there Marcel.
Thank you my fellow man 😉
I haven’t forgotten about EFi , was thinking of finding ways to replace their fuel senders and throttle cables and what not. Sender from a car is possible , i don’t see why not but cables may be from a bike instead. I will do further studies and testing at my end (unless i have someone to test stuff for me haha)Hope you are good!
-
3 questions. I think. Block off the sending unit hole in the tank, go with old school petcock with off, on, and reserve( no standpipe for reserve? no vacuum bullshite, no gauge level.
The fuel pump is gravity-fed. Is it needed due to the orientation of the carbs float bowls or a v twin-specific issue( for the most part I have only dealt with singles or parallel twin carbs)? I have a new one either way.
Question 3? Somewhere on this forum, I saw a post with pics of how to eliminate the air valve thingy. Should the line coming from the base of the rear cylinder have a check valve installed for crankcase ventilation? I might have missed something being a USA citizen (joke).
I’ll expect a reply just as I wake up at 3 am to watch Moto GP live from Assen.-
I answered my own questions: The tank outlet is level or just above the carb inlet. (So the pump is needed),( head pressure and such).
The petcock is situated at the rear middle of the tank. ( so a manual petcock would have to be remote to be accessible ).
And finally just block the pump hole and watch the odometer for range. -
-
-
-
tutorial for egr block off is in tutorials section even for the 650cc is the same principal
tank – how will you know you have low fuel ? the bike behaves worse when fuel level is too low in tank (as quoted from service book)
the vacuum taps are okay , they work nicely with vacuum pump – i tried bypassing, the bikes hate it. so respect to korea for leaving the pump on the frame for high speed runs
-
I may be wrong here: Most cars/trucks I have seen ,the sender unit mounts from the top of the tank down vs a motorcycle. Would that warrant swapping the wires to correct the ohms reading? Also, at least here in the US the first part numbers 34810 match a Suzuki side kick. It all seems to be reversed as far as the photos go.
-
Some unknown sendors will be reversed saying EMTPY on the dash when the tank is actually full, i have experienced this myself. So Hyosung seems to be dead set on their dashboards making sure empty starts at at the base of the tank, as the float goes , the bars on the dash correspond to it.
either way based on my extensive tests of OEM hyosung senders, the ohms in this topic must match (or close to ) whichever sensor you would like to affix to the tank
Hope this helps
Toyota Hilux is common in asian countries where Hyosung is also present as alternative senders.
-
I bought a new sender from a car/truck ; although the mount flange is the same pattern and float arm would need to be modified it works bassakwards as far as resistance goes. Which is what I feared would happen as most cars/trucks level senders are mounted from the top of the tank unlike , I assume most bikes.
I would go with an old-school manual Petcock if the location was reachable. I don’t remember from whom I purchased the thing or what model it fit.
I was probably shopping while drinking and didn’t go from your list of recommendations. Also while drinking : The”SWAP THE WIRES “comment of mine , WHAT AN IDIOT. I’ve got a sender that I bought accidentally with the oval base which I guess is supposed to fit the injected models if someone wants it, just pay for shipping ( I’m in the US) the readings on that are 8.6 ohms empty 97.2 ohms full so this may not be in order either.
Lest I word on more; I think I’ll just seal the broken sender back in the tank and move on to other issues. Thank you for your help.
-
-
For those wondering. CARB bikes with first gen green dashboards (gv/gt650, gt250 / two connectors to the display) have different readings. It’s actually 100 oms – full and 20 – empty. The next gen green dashboard (with a single connector from the board to the display) is apposite. I was surprised recently when was working with dashboards and switching them over. There’s a way to modify the stock 1st gen fuel level sensor. By inverting the position of the float arm to the other side. You’ll need a new steel rod though to shape the new float arm. Works well.
-
- You cannot reply to this topic.