Hello guys, right now I'm fixing up my bike and doing some tune up , but I have a 2 problem that idk how to fix but one I have problem is that my mph is not moving at all. But my rpm and temp and lights are working fine , I bought a used speed senser for 20 and it still not working. And my 2nd problem is that my running tail light is not working no more , but the brake light work fine. And thank you for your help , I'm driving a 1999 cbr f4

 

I'm not entirely sure, maybe my response will garner more interest for you. what I would do is go through the wiring harness with contact cleaner, some q-tips and di-electric grease. Its not a guarantee to fix it but it will benefit the bike immensely and it will strengthen the connections and reliability of the bike. I hope it helps and I hate to see someone who need help not get it.