PDA

View Full Version : Gear indicator Honda CRF 450 X



AnKa
10-09-2012, 10:15 AM
Hi,

We´re trying to figure out a smooth way to get information about which gear the engine is in. There´s nothing in the stock engine which indicatie either gear nor neutral.
Are there anyone here who have experience on this engine and maybe also have solved the gear indication problem?

Kirk Feldkamp
10-09-2012, 11:26 AM
On an engine that doesn't have a gear position sensor, generally it's easiest to use a math channel that compares the engine RPM and the post-tranmission RPM. Most dashes or DAQ systems are already set up to do this. This isn't great for doing things like shift control, but works reasonably well for most simple gear display situations.

-Kirk

Tilman
10-09-2012, 12:51 PM
Heyho,

if there is not even a neutral sensor then things will get complicated.

For our next car our engine guys will fit some "nipples" to the shifting drum that have different resistances to the engine, which is grounded. With a resistance network, voltage divider and an AD converter we can determine the current gear.

Kirk's idea is quite easy if you do not want to modify the engine case. You could fit a hall effect sensor to the small sprocket, for example. However, this will not work reliably if you have a slipper clutch and the car is moving in drag mode (is this the right word?).

If you want to have a sensor for the shift system to determine when the shifting process has finished you better rely on a sensor at the pneumatic cylinder or actuator ...

Moreover I have seen systems where a rotary potentiometer has been mounted inside the engine case and has been driven by a gear on the shifting drum. But this usually requires modifications of the engine case ...

Cardriverx
10-09-2012, 01:28 PM
We run a 600rr, and this year we will be fixing a shaft onto the shifter barrel that sticks out of the engine case with a potentiometer on the end of it. While the speed vs RPM can work, this is really the best way to do it.