Clutch slip calibration problems

[Arska]

Hi

I'm installing sensor to calculate clutch slip, however haven't yet find out how to do it, so let me hear your succestions about the matter.

We have install i88 ECU to our PSB bike which is 3000cc two cylinder dragracing bike, we have primary drive with 0,7105 (54T/76T) ratio and input shaft to gearbox have two teeth to count, which number should I put in the InputShaftSpeedCalibration box to have correct clutch slip in logging. DI2 is turned to freqvence so it should be doing job correctly, and ofcourse source is DI2. Info required soon. We have upcomming race weekend starting from friday, thanks ARSKA

[Scott]

Hi Arska,

Take a look at PCLink > ECU Settings > Chassis and Body > Transmission 

and

PCLink Help > G4+ ECU Tuning Functions > Chassis and Body > Transmission

Once set up correctly the parameter 'Clutch/TC Slip' will provide the data you are looking for.

Scott

[Arska]

Hello

Thanks Scott, for your reply, unfortunately your answer is not helping 'cause I have tryed quite a few different parameter settings and haven't find the right one. In my post tried to give info for calculate right number. What parameters should be? Here is file attached I assum you mentioned. We use VTS 5.3.1.2395 software.

Pls feel free to ask more but we have really tried many different setups and have not yet figured the right one

Thanks

ARSKA

 

ViPec nayttokuva.docx

[Scott]

Hi Arska,

The Input Shaft Calibration number = 60/Number of teeth. In your case you have 2 teeth, so your calibration number should be 30.000.

The input shaft speed will then be 30.000*DI 2 frequency. 

The ECU will then compare engine speed to Input shaft speed and give a slip %.

If you can record a PCLog of what is happening for you we can help work out the problem. I would start by checking that DI 2 frequency is what you expect, and then seeing if the relationship between the DI 2 Frequency and Input Shaft speed is correct.

Scott.

Edited July 14, 2016 by Scott

[Arska]

Hello again Scott

I attached two different log files from cranking the engine 1st gear on clutch fully open then close and end the record, results may be found from below. First record is InputShaftSpeedCal 30.000RPM/Hz and second 65.000RPM/Hz, there is diffence but still not way we needed those to be, well better maybe

Thanks

ARSKA

14072016_Mellila_testi_1_30_arvolla input cal.llg

14072016_Mellila_testi_1_65_arvolla input cal.llg

[Scott]

Hi Arska,

Thanks for the files. Can you confirm for me that on your bike the flywheel attaches to the input shaft via the clutch, and there is nothing to change the ratio? The reason I ask is that in both your log files the DI2 Frequency is not what I would expect with no clutch slip.

In your log with the calibration  at 30.000 RPM/Hz when the input shaft is stable in the log, and the engine speed is 1010, the DI 2 Frequency is 11.0, where-as I would expect a value more like 33.7 Hz (1010/60)*2

In your log with the calibration at 65.000 RPM/Hz  when the input shaft is stable in the log, and the engine speed is 988, the DI 2 Frequency is 21.1, where-as I would expect a value more like 32.9 Hz (988/60)*2

It may be worth examining the signal coming in on DI 2 to confirm the amplitude of the signal is accurate, and that the waveform is as expected.

Scott

Edited July 15, 2016 by Scott
edit so I make sense

[Arska]

Hi Scott

We have separate motor and transmission units so as I mentioned in my first post, primary ratio is 0,7105, front pulley 54T, rear/clutch case pulley 76T. When engine rotates 1 full round the cluth/input shaft goes 0,7105 round. Should this 0,7105 be multiplied by 30? How many rounds does Ecu take to calculate frequence from inputshaft, Asking this for info as there were huge number in begining of record from clutch slip?

Thanks

Arska

 

[Scott]

Hi Arska, 

Thanks for explaining that, I did not understand the drive setup.

I believe an Input Shaft Speed Calibration of 42.630 RPM/Hz will work for you. 60*0.715 = 42.630.

I have tested this on my engine simulator. With an engine speed of 1200 I would expect an input shaft with a 1:1 ratio and two teeth to have a frequency of 40Hz. (1200/60)*2 = 40.

However, as your ratio is 0.7105, I would expect you to have a frequency of 28.42 Hz. 40*0.7105 = 28.42.

I adjusted my DI2 frequency to 28 Hz (closest I can get), and this shows the 'Clutch/TC Slip' as 0.4%, so this confirms that 42.630 would be the calibration number for you to use. Give it a try and let me know if you are successful.

Scott.

 

[Arska]

Thanks Scott, I'll try that setup next when I work with running engine, now I had to do some other things with the motor so next time its drivable I try that. I'll inform if success

Thanks

Arska