Questions about gauges and sending units

[TopCatGr58]

Hey Folks,

I mentioned somewhere on here that I will be putting an aftermarket DASH Tach/Speedo/gauge combo set on my bike. It has the ability to monitor OIL TEMP, as well as FUEL level...not just an idiot light.

The OIL TEMP.....although the ITEM eBay description says OIL MASS....which to me sounds more like PRESSURE.....However I've only seen sending units for oil pressure to be with tubes to run the oil up to the gauge?? And this being a CHEAP Chinese product thinks that it should be using an electrical sending unit...it has a WIRE dedicated to that function. And when I played with the gauge powered up...as I switched thru the gauge display...it would switch from Fuel level to the Oil and it shows a Thermometer symbol...so that's why I think it's a TEMP gauge despite their poor translation of MASS??

SO...anyways...I've found a sender with a range of 140 to 320 degrees....others were lower ranges but I think they were for WATER. But the description doesn't say what the OHM range the sender works at? I've written to the site that sells the sender..the same place that I get my fuseblocks from....asking them if they can tell me the operational ohm range.

The Gauge/dash cluster says that it can work with senders that work at either 100 ohms or 500 ohms. Doesn't anyone KNOW what or if there is a common OHM range for Oil temp sending units??

I've have a Special, with an XJ tank, but I swapped out the sending units so that it would match my Special gauge/light. I think the XJ float was damaged anyways. But I did find that the XJ gauge used a sender that worked in the 20 Ohm to 320 Ohm for empty to full. I've found a generic sending unit that is adjustable from 4.5" to 21"....I'm assuming the length of the float arm, and it also works in the same/similar OHM range. SO...I'm hoping to be able to mount it INSIDE my XJ tank and have an actual fuel gauge as well instead of an idiot light.

What I've got to figure out is whether I would need a right handed or left handed style. The Special tank sender is on the Right hand side of the tunnel, but the XJ's is on the left hand side of the tunnel. SO..looking into the tank from the tunnel, the larger deeper portion of the tank will be to the right. The generic fuel sender is available in both right and left handed styles, but I don't know how they are really oriented?

The Gauge cluster is designed for SCOOTERS, small motorcycles...like Vespa's and such. Does anyone know what the OHM range of the fuel senders for these types of scoooters work at??

It may be a moot point because with the float low it should have the least amount of resistance...and so hopefully that will show up on the gauge fairly low on the scale? Seems like a fuel gauge is really just a fancy specially purposed OHM gauge? Once I get it figured out, I'll be posting a thread/tip about it, how to wire one up, etc., so that it will also have applications and info for folks wanting to put aftermarket gauges on and what will work, etc.!

T.C.

[jetmechmarty]

What does your new setup look like?

I have seen bikes running Acewell meters. They get good reviews. It appears they tolerate the XS650 vibration very well.

[IanDMacDonald]

I believe Gallaceus/Garamangus has the Acewell on his bike.

[CaptonZap]

Hey Folks,


The Gauge cluster is designed for SCOOTERS, small motorcycles...like Vespa's and such. Does anyone know what the OHM range of the fuel senders for these types of scoooters work at??


T.C.

110 ohms empty, 50cc Kymco. Cant tell full, because I would have to pull the tank out to get the sender out, or fill the tank on a dead scooter.
Wait a minute, a wire pull may do the trick. I'll be back in a few.

OK, 110 empty, and 9 ohms full.
The gauge is a volt meter, which measures the voltage drop through the sender resistence. You supply 12+/- volts to the sender when you turn on the key, and the sender drops that according to the resistence, and the gauge reads the results.

CZ

[TopCatGr58]

Hey Marty/Ian,

I'm sure that Acewell is a nice gauge....but it's a $200+ price range, and remember, we're cheap bastards here on channel 11! The one I got from eBay/China was only $50.00 WITH shipping, and it's got a bigger dial and layout so that my OLD eyes can more easily see things on it, not all cramped up inside a little ~2" round gauges!?

CZ, thanks for that info. I was first trying to see if I had an old Potentiometer laying around that I could put on the gauge to see what ranges of resistance I could create and what the gauge would do/show.

But I didn't have one! I did find a basic RELAY and the 85-86 terminals had about 75 OHMS, so I was able to put that LOAD on the gauge and at least I got the readout to stop just BLINKING!! The OIL temp showed just a few bars in the COLD range. The Fuel sender seemed to show almost FULL?? I wish I had a POT that I could create a variable amount of resistance to see what range it will work/read at?

Guess I'll just have to get the float/sender and play with it to see what it shows. I'm not too worried about true accuracy, just that it will be nice to be able to see/tell that it's getting low vs. waiting for the RED LIGHT to come on and then only have 20 miles range!?

Hopefully DelCity will write me back tomorrow(Business day) and let me know what OHM range the OIL temp sender works at. Does the 140 to 320 temp range sound right for OIL vs. only up to 240/280 for water?

T.C.

[crazy steve]

Does the 140 to 320 temp range sound right for OIL vs. only up to 240/280 for water?

Either range should work for oil temp, although you want more than 240 for oil and if you see 300+ you have a problem...

Unfortunately, gauges don't have 'standard' sensor ranges, some even work 'backwards' so you may have to do some hunting to find something that works and is affordable....

[TopCatGr58]

Hey Steve,

Thanks! I could have sworn that when I was looking at a fuel sender/float assembly that when the float was LOW the contact arm was very close to the end of the coil so that it would not have had very much resistance which would indicate a LOW FUEL level, but CZ's readings suggest the opposite?

So...you would suggest that I get an OIL sender unit with a max range of 280 degrees!? The gauge just shows vertical BARS with a little thermometer graphic, but no actual degrees readout, just that it's programmable for either a 100 ohm or 500 ohm sender??

T.C.

[James England]

I have a Stack oil temperature gauge on my XJR. It is electrical and uses a sender which screws straight into the oil sump by removing an OEM blanking bolt. The gauge calibrates itself each time the ignition switch is turned on. It's been very reliable in the 9 months it's been on and was easy to fit. I find it reassuring to have a temp gauge as I fitted a Mocal oil thermostat into the oil cooler pipes, so it's a good way of verifying that the thermostat is operating correctly.







Here's the sensor in the oil sump..

[crazy steve]

T.C., you really need to know how the gauge is 'set-up' internally to select a sending unit. As an example, there's at least six different 'ohm ranges' used in 'most' automotive fuel level gauges among the major car manufacturers, and yet different ones for 'odd' makes or years.

With a gauge that has no 'values' on the gauge face (merely from 'low' to 'high'), you can 'calibrate' the gauge to read anything you want... with the right sending unit. The problem is two-fold; first, what ohm value at the sending unit corresponds to what gauge indication? As you mentioned, the easiest way to check that is with a variable potentiometer, but you may need to be careful not to expose the gauge to a too-low resistance or too much current flow may damage it. After you determine that, then it's a matter of finding a sending unit that has an ohms 'range' that matches the gauge and 'reads' the desired 'quantity' that you want to measure.

As an example, if the gauge reads 'zero' at 30 ohms and 'maximum' scale at 100 ohms and the desired measuring range is 140-280 degrees, you need a sending unit that reads 30 ohms @ 120 and 100 ohms @ 280. The key item here is the range; 70 ohms difference. If your sending unit 'range' is larger/smaller than 70 ohms (say 10 ohms to 120 ohms or 30 to 70 ohms), accuracy will suffer and there's a possibility of gauge damage. But if you can find a sending unit with the right 70 ohm 'range' but a lower low/high resistance, you can install a resistor in series to 'correct' it. Too high won't work.

Not to be discouraging, but finding a 'correct' sending unit may be a can of worms if the gauge manufacturer is no help. There's literally dozens of units out there; you'll have to research the OEM units as the electrical specs are rarely given, but most aftermarket units will give the range or the manufacturer will tell you if you ask.

Hope this helps, good luck!

[TopCatGr58]

Hey Steve,

Yep, I'm learning a bit about gauges, senders, and such. The gauge I have has a built in protection circuit, when I connected the sender wire to direct ground=0 ohms, it just blinks the display. It was when I connected it to the load is when it stabilized. I just checked RS and they have a 5K ohm Pot for $3.49. The only other one is a 25 ohm, and that's just too low.

I've been looking closely at the fuel senders, and the Universal ones are designed mostly for AUTOMOTIVE style tanks where the sender bolts into the TOP of the tank, and the sending wire connection is on the outside of the mounting plate....similar to our bikes units with external sender connections.

However, ours are side mounted. The Stewart Warner side/R/L/handed style can be set for ~6", so it should be able to fit INSIDE the tank. The Float arm can be BENT/adjusted depending on the positon of the mounting base plate. My other concern is mounting the float assembly completely on the INSIDE of the tank...using an L bracket or such to attach it to the OEM plate/mounting holes. And so I want to connect the sending wire connection from the new universal unit to the Inside of the OEM plate, so that I can still use the OUTSIDE of the OEM plate and it's wire connection for the sending unit wire.

Will the wire inside the tank...being exposed to the fuel still work? The sender will ground thru the base/L bracket to tank/frame. I don't know if fuel is very conductive or not? I think I remember that the OEM sender grounds thru the harness and not to the tank casing itself....I may also need to connect the new sender to ensure it connects to the ground connector on the OEM plate.
Does this sound workable?

CZ posted that the scooter gauge/sender he had worked in the ~20-110 ohm range. This gauge cluster states it's for Scooters, but also for Motorcycles, so I'm just going to have to test it with a POT and Ohmeter to verify what it will read, the range. The universal floats are available in the 110 or 240 ohm ranges.

T.C.

[crazy steve]

Will the wire inside the tank...being exposed to the fuel still work? The sender will ground thru the base/L bracket to tank/frame. I don't know if fuel is very conductive or not? I think I remember that the OEM sender grounds thru the harness and not to the tank casing itself....I may also need to connect the new sender to ensure it connects to the ground connector on the OEM plate.
Does this sound workable?

Fuel isn't conductive (or enough to matter) so that's not an issue, but you don't want any wire to the 'new' sender come outside the tank unless it goes through some sort of bulkhead fitting. One, gas will probably eat up the plastic insulation fairly quickly (most are only 'gasoline resistant'), and two, you don't want fuel 'wicking' through the wire.

Yes, you'll need a ground to the new sender baseplate. Remember, the tank is rubber mounted....

[TopCatGr58]

Well, I've been doing a little more research, and then thought about why try to re-invent the wheel, and so I checked eBay to see if there were any XJ11 fuel tank senders on there. I didn't see any, but I did see an XJ650LK, and the mounting plate looked similar to the XJ'11's, AND the XS11. So I looked it up on the Yamaha Fiche site, and sure enough....the GASKET for the plate has the 2H7 prefix....so it's the same BOLT LAYOUT as the XS11.

SO...I just need to be sure that where the sender is mounted is on the same side as the XJ11 for the sender to work correctly and not be upside down. And the XJ11 manual stated that it works in the 240 ohm range. I just picked up a Pot and will be testing the Gauge this evening to see what range it reads...I'm hoping and expecting it to be within the same Stewart Warner Standard range of 240...but we'll see! I'll also check out the OIL Temp as well, but I still haven't heard from Del City regarding the Oil temp sensor range.

But being able to use an OEM bike sender will solve my connection problem as well as mounting position problem.

T.C.

[IanDMacDonald]

I'm excited to see the final showing of this project. I know of a few members whom post about Acewell's, etc., but we never find-out if they are full-functioning.

[D0wn5h1ft]

Are there any bolt-on oil temp sensors for our XS11s like the one James posted? I'm trying to make some pretty long distance trips this summer and one of the things that makes me nervous is engine overheating from cruising at highways speed for hundreds of miles. With student loans looming on my horizon, I'd be hard pressed to come up with the cash to tow my a$$ back to wherever I start out from if I blow up my engine. I'd love to be able to monitor temps on the road without having to pull over.

[bikerphil]

Should be able to rig up just about any oil temp sensor, it could go into a custom made pan drain plug, then up to a gauge. JAT

Edit: I've seen fellas bore a hole in the side of the oil pan and install one there.