I usually see a straight line during 2 or 3 seconds on the RPM graph just when release the throttle. I dont know what is happening.
I am using the last version of DL1 firmware and analysis software. Someone with similar problem can help me wrong RPM
wrong RPM
Hello, sorry for my english. I will try to explain my problem.
I usually see a straight line during 2 or 3 seconds on the RPM graph just when release the throttle. I dont know what is happening. I am using the last version of DL1 firmware and analysis software. Someone with similar problem can help me
I usually see a straight line during 2 or 3 seconds on the RPM graph just when release the throttle. I dont know what is happening.
I am using the last version of DL1 firmware and analysis software. Someone with similar problem can help me Re: wrong RPM
Details on the vehicle?
Is it possible that your particular vehicle measures RPM from the ECU, and the ECU is shutting off the ignition with throttle closure, as some cars do with injector pulse width?
Is it possible that your particular vehicle measures RPM from the ECU, and the ECU is shutting off the ignition with throttle closure, as some cars do with injector pulse width?
You have not given enough information for me to advise a definitive decrease or increase, but it is the "Maximum rate of change" setting (max. r.o.c.) that I think you need to change.
This is found in the Variable Manager under "Advanced options".
You have not said so, but I am assuming that some of the RPM trace is sensible and properly scaled. Therefore, I assume that the "Ignition Pulses Per Revolution", which lives under "Vehicle Options"in the Data menu is correctly set.
If you are not sure, log some data driving at constant speed in different gears. I assume that you know or can find out your gear ratios. The effective tyre circumference is less than that which you measure on an unladen tyre. A better measurement is to roll the car for a few complete wheel revolutions and measure the distance...
The relationship between RPM and speed should thus be known...
Thanks to our GPS, we do not need to measure circumference directly as long as we know the gearing numbers.
If gear ratios are unknown, you can still check for sensible RPM measurement by checking to see that speed and RPM stay in the proportion to each other at different road speeds in the same gear. If the max. r.o.c. is not properly set, this proportion can change.
The setting is not critical to within a hundred or so... it is unlikely that 2400 works but 2500 does not. Rather, if 2500 is not OK, 1500 or 5000 should be tried, for instance.
If I have to guess, I'll say that your max r.o.c. is set too low. If it is too high, you would probably be complaining of inexplicable peaks in the RPM data.
This is found in the Variable Manager under "Advanced options".
You have not said so, but I am assuming that some of the RPM trace is sensible and properly scaled. Therefore, I assume that the "Ignition Pulses Per Revolution", which lives under "Vehicle Options"in the Data menu is correctly set.
If you are not sure, log some data driving at constant speed in different gears. I assume that you know or can find out your gear ratios. The effective tyre circumference is less than that which you measure on an unladen tyre. A better measurement is to roll the car for a few complete wheel revolutions and measure the distance...
The relationship between RPM and speed should thus be known...
Thanks to our GPS, we do not need to measure circumference directly as long as we know the gearing numbers.
If gear ratios are unknown, you can still check for sensible RPM measurement by checking to see that speed and RPM stay in the proportion to each other at different road speeds in the same gear. If the max. r.o.c. is not properly set, this proportion can change.
The setting is not critical to within a hundred or so... it is unlikely that 2400 works but 2500 does not. Rather, if 2500 is not OK, 1500 or 5000 should be tried, for instance.
If I have to guess, I'll say that your max r.o.c. is set too low. If it is too high, you would probably be complaining of inexplicable peaks in the RPM data.
Re: wrong RPM
The vehicle is Honda CBR1000 year07
I am taking signal from the wire wich goes from ECU to tacho and connect it to the rL input of the DL1
I am taking signal from the wire wich goes from ECU to tacho and connect it to the rL input of the DL1
So it is a 4-cyl 4-stroke, the default setting, I expect, whatever version software you have.
Perhaps someone has some experience with this machine.
There are certainly some other DL1 users with 4-cyl Honda bike engines in sports cars.
The problem in RPM measurements for all data loggers is noise. Noise causes spikes that are interpreted as the RPM increasing. A neat way to filter out this noise is to use the knowledge that revs can increase only so quickly...
Do not just wait until someone tells you what setting to use.
The noise in your sytsem might be different from another same year CBR, just because a wiring loom may run a centimetre or so differently...
Just experiment with the data you already have logged.
Perhaps someone has some experience with this machine.
There are certainly some other DL1 users with 4-cyl Honda bike engines in sports cars.
The problem in RPM measurements for all data loggers is noise. Noise causes spikes that are interpreted as the RPM increasing. A neat way to filter out this noise is to use the knowledge that revs can increase only so quickly...
Do not just wait until someone tells you what setting to use.
The noise in your sytsem might be different from another same year CBR, just because a wiring loom may run a centimetre or so differently...
Just experiment with the data you already have logged.
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