Motorcycle Questions? Ask a Mechanic.
If the check engine light came on there should be a stored code. I have seen instances where it does like yours and a code is not present.
This system uses two throttle position sensors at the throttle body when there is no input from both it goes into idle mode where turning the throttle has no effect. IF only one fails you get a limited throttle.
In your case where both fail and an ignition cycle resets it's either an ecm, software or electrical wiring issue.
The dealer can test these sensors and the wiring with no codes present.
You're welcome, the aftermarket ones run around 35.00 OEM will be slightly higher.