Clear all

Engine rpm same as RPM1

2 Posts
2 Users
Posts: 3
Topic starter


Hi, I have an inertia dyno for mopeds.

The Reading from the Engine rpm is the same as the Readings from RPM1 (roller rpm is correct)

I use an inductive clamp. I tried to disconnect the Roller RPM from the hardware and see if the program would show just the Engine RPM which didn’t work.

Do you think the problem is with some option in the software that is wrong, or does it have anything to to with the shielding of the cabels in dyno? Or if the Roller rpm disturb the Engine rpm or vice versa?


Posted : 17/08/2023 7:13 pm
Posts: 1299
Member Admin


This can be confusing, but the Engine RPM is equal to roller RPM * Gear ratio. This is the main RPM that the system is using to calculate engine power, torque etc and to control the brake when fitted. It is always related to the roller RPM, which is where all power/torque are measured.

If you have an inductive RPM pickup then call the channel something for example RPM Pickup. It will show the direct engine RPM. You can then compare the two by plotting them together, or create a math channel for Slip (Slip = "RPM Pickup" - "Engine RPM"), and of course use the RPM Pickup when setting the gear ratio.

Posted : 23/08/2023 11:26 am
Select your currency