1999 r6 wear is the speedo sensor - 1999 Yamaha YZF-R6

hi

this is may be the sensor which read the speed of the bike may be damaged.try changing the sensor.
2.if stil problem presists then check the cable which transmitts the signal to the speedo meter. this may be damaged so replace the wire.
3.if stil the problem presists then the problem is with speedo meter only. so change the speedo meter

first, check you battery terminals, make sure they are clean and tight.

Speed sprocket is on leftside of front wheel. Disconnect speedo cable from under speedometer itself and turn front wheel to see if cable turns. If not dis connect at front wheel and try turning cable, it's a squared pieces of cable inside black casing. If you can pull both ends out then it is definetly broken. This is much more likely than breaking the speedo sprocket on front wheel. If it is speedo sprocket, get a new one and remove front wheel , change sprocket and reassemble. If Speedo sprocket is being stubborn coming out use something relatively soft and tap it out. Good Luck.

Check internal splines on front drive sprocket.

Hi and welcome to FixYa,

Offhand, it would appear that some of the contacts of the main (ignition) switch has fused together. To check, with the ignition switch off and key removed, all wires from the ignition switch must have no 12 volts reading except for the red.

Good luck and thank you for asking FixYa.