GAS GAS 450 SM starting problem
 

hi guys
i have a 2006 Gas Gas 450 sm. the bike starts well the first time each morning but then it become very difficult even impossible (until buttery dies) to start. my mechanic says that the diagnostic states that is the bike read -16 degress temp so thats why does not start.... we change the cdi but it was not the solution.... ANY IDEAS?????? PLS HELP!!!

My first thought is that a -16 temp reading to ECU will start cold but should flood when started hot. IF it has clear flood mode as most do, trying hot starting with wide open throttle, it should start that way & although it would run very rich it should run. CDI does not control this- more likely a faulty OR poorly connected temp sensor, (sorry- no idea where it is located but check coolant hoses and passage ways for a sensor) or wiring between ECU and temp sensor.

You also want to make sure your buttery has a full charge :-)

I'm speaking from a basic fuel injection theory of operation standpoint so I can't help much further. Hope this helps

hi fred thanks for the infos... actully the situation is as u describe... will try to change the sensor....

unfortunately we change the sensor but still the same problem.... refuse to start...

Does it still have the same -16 readout?
Is it the Air or Water temp sensor?

What happens if you disconnect the sensor and do a ECU readout? If it is still the same it indicates a possible fault in your wiring harness, probably a short.

It might also be the ECU itself