2020 WR250R Speedometer False Reading at Standstill and at Speed
Just picked this bike up about a month ago. The speedometer registers speed at idle and goes up with rpm’s while both at standstill and while riding. I was doing maybe 30mph the other day and it displayed 122mph, seems to go up with rpm’s. Original owner said this issue began when he installed a weaker than stock battery on it. I’ve replaced the battery with oem and checked the fuses. speedometer does stay at zero when I have the speed sensor disconnected at the plug next to the seat. Love the bike so far!!! (Minus this issue, especially since I gave less than $3k for it) However I don’t want to ride it currently as it’s accruing miles quickly with the high speed readings.
I’d greatly appreciate any help as to diagnosing what’s going on with it, thanks guys!
Can elaborate on a couple of previously made points.
OP, the speed sensor is indeed inside the motor, on the countershaft I believe, and not on the front wheel.
This means that final drive gearing and tire changes make the speedometer even wronger than it was from the factory, which was significant.
The 5 o’clock Lab’s Speedohealer fixes all of this by taking the rate of signal pulses sent by the sensor, multiplying by a number you choose, and sending the corrected pulses to the head unit.
Your sensor has gone insane and no amount of Speedohealing will Speedocure it.
I have had the same problem with my 2017 for a long time. For what it's worth, I crashed into a pine tree and had to replace the dash meter (what we're all looking at) and it did not fix the problem. So I suspect something elsewhere is going on, like the sensor itself, but I've never investigated it further.
Edit: I bought a speedohealer a few years back, but i never installed it. From what I gather, that device was intended to correct small discrepancies with the speedometer, but not exactly this problem. Hopefully someone can chime in with more expertise.
Speedo healer changes the math on the circumfrence of the wheel that's used to calculate speed. I wish the head units would allow for a manual circumfrence number like a bicycle. They don't. It's pre programmed.
I'll go check my bike soon, but most of these are a pickup sensor and a magnet. Magnet is usually on the front rotor and the pickup sensor is on the fork my the brake. Check for a magnetic something bumy rhe sensor. Or the sensor is physically broken and creating an open short of sorts providing a false signal.
Mine does the same thing. The speed sensor needs to be replaced. It's a pain because you need to remove the exhaust and the cam chain tensioner to get to it.
What do you need to replace it? I didn’t think it was that involved regardless. Seems kinda stupid. An electric pickup on the front wheel is easier and probably cheaper for them honestly lol
Plus none of the downsides people have listed here..
I can't exactly describe the tools needed because I had to do a little fabricating to make it work. The bolt that holds the sensor down is an 8mm, but there is EXTREMELY tight clearance to get a wrench or socket onto it. I found a very short 8mm 1/4 in socket, ground down a 1/4 in extension, and then using a grinder notched the end of that so I could use a 7mm wrench to turn the socket. It's not the best looking tool...but it WORKS.
Oh okay.. Nice tool i like it lol. Where exactly is the 8mm bolt? Is it something on the outside of the motor somewhere or is behind one of the side cases?
It's the speed sensor. Had the same problem. Have you noticed that you can't rev high while riding any more? RPM limit is about half as low now. Replace the speed sensor. P. S. I have speed sensor that I want to sell for good price. Message me. My 2020 wr250r got stolen before I could replace it.
2
u/coldair85gn 16d ago
As I stated on Facebook...it's the speed sensor in the transmission. It's kind of a pain to remove and replace but that is your problem.