Day/Night Temp Fluctuation: Tuner Trivia
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- Wheelman-111
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Day/Night Temp Fluctuation: Tuner Trivia
Greetings:
See Scooter Builds Flash III Chronicles for the full story.
Good morning, kids! In our last episode, a smug Wheelman was ever so certain he'd found the 109 to be the Magic Jet for the stock carb with the 78cc setup. Comfortably cool during testing last night, even after a good spell at WOT. So we're done until break-in stage is over, right? Maybe Not!
Now this morning, with ambient air temps easily 15 degrees cooler, it's running warmer again. Pretty much stuck at 370-400 at steady-state cruising and without throttle abuse. What makes an engine run 325 at night and 375 the next morning? Humidity? Bad eyesight??
Moving the clip down helped a little, but still nudges 400 more often than I'd like.
I need to tune for average conditions, so I'll break out the drills again tonight. Sheesh!
See Scooter Builds Flash III Chronicles for the full story.
Good morning, kids! In our last episode, a smug Wheelman was ever so certain he'd found the 109 to be the Magic Jet for the stock carb with the 78cc setup. Comfortably cool during testing last night, even after a good spell at WOT. So we're done until break-in stage is over, right? Maybe Not!
Now this morning, with ambient air temps easily 15 degrees cooler, it's running warmer again. Pretty much stuck at 370-400 at steady-state cruising and without throttle abuse. What makes an engine run 325 at night and 375 the next morning? Humidity? Bad eyesight??
Moving the clip down helped a little, but still nudges 400 more often than I'd like.
I need to tune for average conditions, so I'll break out the drills again tonight. Sheesh!
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
- bradthreee
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Re: Day/Night Temp Fluctuation: Tuner Trivia
Put the drill away and wait a couple of days for the real thing to show up in your mailbox
- Wheelman-111
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Drilling Jets
Greetings:
Wise B3 suggests:
Wise B3 suggests:
Quite true that the bore size of the jet is only one factor in how much fuel it flows. I'm still at a loss to explain the differing temps observed lately.Put the drill away and wait a couple of days for the real thing to show up in your mailbox
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
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Re: Day/Night Temp Fluctuation: Tuner Trivia
Haven't found any mfg data for the VDO gauge as to whether or not it is temperature compensated. If it is not, it will read much differently between cold and garaged in the morning vs out in the heat and sun of the afternoon.
Info below is from the Westach CHT meter:
See pic below. Westach describes the ambient temperature impact to readings.
Another source of error is shown in the Westach schematic. They show the thermocouple being wired to a 'patch cable' extension. If the splice is not thermocouple wire and is made where it is hot (like in the engine compartment), there will be increased error. Many would say run an *unbroken* length of thermocouple wire up to the meter.
The wiring splice example important because even if a meter has temperature compensation, it's cannot adjust for an unknown splice temperature.
Info from Westach 2C1 CHT gauge instructions
Edit: 11/25/2013 Pic above was lost due to a photo hosting service change. Pic below is substituted.
Info below is from the Westach CHT meter:
See pic below. Westach describes the ambient temperature impact to readings.
Another source of error is shown in the Westach schematic. They show the thermocouple being wired to a 'patch cable' extension. If the splice is not thermocouple wire and is made where it is hot (like in the engine compartment), there will be increased error. Many would say run an *unbroken* length of thermocouple wire up to the meter.
The wiring splice example important because even if a meter has temperature compensation, it's cannot adjust for an unknown splice temperature.
Info from Westach 2C1 CHT gauge instructions
Edit: 11/25/2013 Pic above was lost due to a photo hosting service change. Pic below is substituted.
- Wheelman-111
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MouseWheels Is Da 'Lectrical MAN!
Greetings:
Mr. Mouse, you dunnit again!
First of all, the Westach uses a type "J", which is encouraging if my VDO uses the same system. Pretty safe bet?
Second, the "Reads Hot When Cold" idea perfectly matches my observations. I do have a splice pretty close to the sender, inside the rear panels. Evidently there's no thermal compensation on mine.
Some of these issues are about to be resolved, however. I took a chance and ordered this Type "J" from Grainger:
One drawback was the $29 price tag. Another was that the choices were between 4' and 12' of lead wire. At least I can coil up the 7' of excess under the front cover. The good news is that all of it is metal-jacketed, fiberglass-insulated top-quality material. The ring lug is a 1/4", so it'll tuck safely away from marauding Wheelhands attacking the spark plug every other day. It's going to a headbolt instead. I'll try your suggestion and test with a cup of boiling water to get a baseline error estimate.
Thanks Mouse!
Mr. Mouse, you dunnit again!
First of all, the Westach uses a type "J", which is encouraging if my VDO uses the same system. Pretty safe bet?
Second, the "Reads Hot When Cold" idea perfectly matches my observations. I do have a splice pretty close to the sender, inside the rear panels. Evidently there's no thermal compensation on mine.
Some of these issues are about to be resolved, however. I took a chance and ordered this Type "J" from Grainger:
One drawback was the $29 price tag. Another was that the choices were between 4' and 12' of lead wire. At least I can coil up the 7' of excess under the front cover. The good news is that all of it is metal-jacketed, fiberglass-insulated top-quality material. The ring lug is a 1/4", so it'll tuck safely away from marauding Wheelhands attacking the spark plug every other day. It's going to a headbolt instead. I'll try your suggestion and test with a cup of boiling water to get a baseline error estimate.
Thanks Mouse!
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
- Wheelman-111
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Scalding Hot Water = ? 150
Greetings:
Tried the dip test with the Grainger probe. Transferred boiling water to a travel mug and got it to the hooked-up probe within a minute. Gauge responded with a reading of 150. Close enough?
Nothing to lose so I trimmed the 12' metal-jacketed wire to 6' with similar results. Water sure seemed hotter than 150...air temps around 85, no splice in the wire.
Tried the dip test with the Grainger probe. Transferred boiling water to a travel mug and got it to the hooked-up probe within a minute. Gauge responded with a reading of 150. Close enough?
Nothing to lose so I trimmed the 12' metal-jacketed wire to 6' with similar results. Water sure seemed hotter than 150...air temps around 85, no splice in the wire.
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
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Re: Day/Night Temp Fluctuation: Tuner Trivia
Definitely the VDO does not use a 'K type' thermocouple, it would read even lower.Wheelman wrote:Transferred boiling water to a travel mug and got it to the hooked-up probe within a minute. Gauge responded with a reading of 150. Close enough? Nothing to lose so I trimmed the 12' metal-jacketed wire to 6' with similar results. Water sure seemed hotter than 150...air temps around 85, no splice in the wire.
Edit (addition) The 'J' type may be correct, and the meter reads low. Below, is a 'what if'...
There is a higher output voltage thermocouple Type 'E'. The 'E' Type would read approx (150 * 68/55) = 185 degrees + 10 ambient compensation ==> 195.
How did it look on this mornings ride?
- Wheelman-111
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Re: Day/Night Temp Fluctuation: Tuner Trivia
Greetings:
That E-type sounds like the correct calibration doesn't it. I'm pretty sure that cup o'water was still hotter than 180. Lip-burning hot.
Now who carries an "E" thermocouple?? I have my original VDO that I'd written off because it began working intermittently. Can I measure it somehow? (Have Multi-Meter.) Crimp on a 1/4" ring and slip it under a head bolt??
That E-type sounds like the correct calibration doesn't it. I'm pretty sure that cup o'water was still hotter than 180. Lip-burning hot.
Now who carries an "E" thermocouple?? I have my original VDO that I'd written off because it began working intermittently. Can I measure it somehow? (Have Multi-Meter.) Crimp on a 1/4" ring and slip it under a head bolt??
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
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Re: Day/Night Temp Fluctuation: Tuner Trivia
Sure, DMM test is good, use the 200mV DC scale. Be easier to run the test in your kitchen with boiling water. Tested on the scooter, we'd want to know accurate head temperature .Wheelman-111 wrote:I have my original VDO that I'd written off because it began working intermittently. Can I measure it somehow? (Have Multi-Meter.) Crimp on a 1/4" ring and slip it under a head bolt??
Update
Added tables of input temperature (left col) vs expected voltage output (far right col) for 3 common thermocouple types. In the middle is the process to 'compensate' for 70F temperature at the meter side of the thermocouple. With a 200mv scale DMM limit on a common 3 1/2 digit DMM, the signal is in the last digit of the meter. An oven will help to increase measured voltage.
Also, PM if interested in sending a couple inches of thermocouple wire. Will ID the type with an industrial thermocouple meter. It has switch settings for E,J,K.
Re: Day/Night Temp Fluctuation: Tuner Trivia
All i can say about you kidz is both of you have no clue on how to build an engine
some people dream of speed, i own your dreams!
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Re: Day/Night Temp Fluctuation: Tuner Trivia
Hi maddog! This should save some $$$ for the the good stuff8) Why be paying $30 or more for a factory thermocouple?All i can say about you kidz is both of you have no clue on how to build an engine
Armed with this table is anyone here can test and identify what their CHT or EGT uses for a thermocouple, then get wire or probes from a lower cost source.
A test of the process was run at home, with an 'unknown probe' in a junk box.
Kitchen was 81F, probe in boiling water. Adjusted the compensation voltage to match. The closest table fitting is the 'K type' the unknown probe was within 1% of expected output voltage for a 'K' probe. It's clearly a 'K' nothing else is close!
The test is this simple
To ID an unknown thermocouple, test with the DMM close to 70F:
1)Put probe in boiling water
2)Measure the themocouple output voltage. 3.25 mV = 'K' type, 4.19 mV = J, 5.06mV is 'E' type.
If your meter cannot read into the decimal places, test at a higher temperature
1) Place in 400F oven
2) Measured themocouple voltage of 7 to 8 mv it 'K', 10mv is "J", 12 mV is "E"
----- Actual values would be (7.47 is 'K' , 9.95mV is "J' , 12.31 is 'E') if your meter could display the extra digits.
- Wheelman-111
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Some People....
Greetings:
Good info, Mouse. If I could boil water, I'd try it out but lack the cooking skills.
I'll pull out the old original VDO sender and see if it works at all.
If only someone could condescend me an engine-building clue...
Some people dress in tweed. I've sewn your dreams.
Good info, Mouse. If I could boil water, I'd try it out but lack the cooking skills.
I'll pull out the old original VDO sender and see if it works at all.
If only someone could condescend me an engine-building clue...
Some people dress in tweed. I've sewn your dreams.
- Wheelman-111
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VDO = Type "J" Thermocouple
Greetings:
Both my VDO and my cut-down TRW 6' solid wire read 3.5 mV in boiling water.
At least now we know which type the VDO requires. Is it possible my third probe from Aircraft Spruce is a Type E? That would explain alarming readings with good engine performance. Too late to pull it off tonight.
Both my VDO and my cut-down TRW 6' solid wire read 3.5 mV in boiling water.
At least now we know which type the VDO requires. Is it possible my third probe from Aircraft Spruce is a Type E? That would explain alarming readings with good engine performance. Too late to pull it off tonight.
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
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Re: Day/Night Temp Fluctuation: Tuner Trivia
Argh sure would, so many different CHT probes!Wheelman-111 wrote:Is it possible my third probe from Aircraft Spruce is a Type E? That would explain alarming readings with good engine performance.
- Wheelman-111
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Conversion Factor E to J
Greetings
I went poking around for my CHT probe receipt without success. What do you think my peak temps of 450 would be on a J probe if in fact I've got a Type E? Gauge scale is 0 at 100F.
I went poking around for my CHT probe receipt without success. What do you think my peak temps of 450 would be on a J probe if in fact I've got a Type E? Gauge scale is 0 at 100F.
Wheelman-111
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH
Most of my money is spent on scooterparts. The rest is just wasted.
"ISO": '03 Vespa ET4 Malossi187 74MPH
Flash 9: 2001 Elite SR Contesta 72 ZX Tran, 9:1 Gears, Stock Airbox/Carb/Pipe 58.8 MPH
Punkin: 2010 Vespa/Malossi S78, 61MPH