I’m new too this forum, i searched but could find an answer to my problem. My 2004 Honda Rincon 650 is showing a 4 flash code and won’t shift up. this code says it the rear speed sensor. So….i search hi and low for a rear speed sensor in the area of the read diff but found nothing. Some threads on this site even talked about a sensor just forward of the rear diff…..but i cant find one. All i can find is the speed sensor on the front diff and what they call the "rear speed sensor" on the back of the front diff. So…..there are 2 speed sensors on the front diff. So is the "rear speed sensor" on the front diff my problem? am i missing a sensor on the rear diff? any help, thanks.