rtp Posted March 25, 2011 Share Posted March 25, 2011 I have a 2004 R1150RT-P (new for me last year). I've noticed that at times, my speedo goes crazy. The needle jumps all over the place, sometimes showing a super fast speed, other times just bouncing. Doesnt happen all the time. I've noticed that when I have the heated grips on it seems more predictable. Anyone else out there run into anything like this? I was thinking it might be a connector but if its related to the grips, then it would be some kind of interference. Link to comment
Boffin Posted March 25, 2011 Share Posted March 25, 2011 The speedo is cable driven, not electronic. My guess would be a kinked cable. Andy Link to comment
scout6 Posted March 25, 2011 Share Posted March 25, 2011 If a wheel was recently removed, plastic dogs that drive the metal tangs in the hub on the front wheel might not be lined up. Also, they might be rounded or stretched to the point of not working all the time. I had this happen last year after changing a tire. The dealer swapped the cable. Did not work. I pulled the hub off a parts bike we have in the garage and changed it out. Speedo again working. Link to comment
dirtrider Posted March 25, 2011 Share Posted March 25, 2011 Afternoon RTP While it could be about anything in the speedometer system from a buggerred drive/driven gear, to a dry or kinked drive cable, to a problem in the spedo head itself. About all you can do is pull the drive/driven gear out then check it for wear or lack of lube, check the cable routing and cable for kinks, then remove inner cable from the housing then clean and lubricate it. If it still acts up your problem is then more than likely in the spedo head itself. Unfortunately it has been my experience that a problem like you describe is unusually in the spedo head itself (you’ll be very lucky if it isn’t) If the problem turns out to be in the head itself-- with a lots of energy and precision and a lot of ingenuity you can remove the bezel and lens then clean it up inside and lubricate the inner workings. Sometimes that is enough to make it work right again. Do the easy things first like cable lube and drive/driven gear check and lube. Link to comment
Quinn Posted March 25, 2011 Share Posted March 25, 2011 My dealer told me that it's almost always to cable getting frayed and binding. So far, that's fixed it for me. --- Link to comment
Polo Posted March 25, 2011 Share Posted March 25, 2011 You can try this not so crazy one. Sorry, but that's what I thought when I saw the title of the post. Back to the scheduled programming. Link to comment
flars Posted March 27, 2011 Share Posted March 27, 2011 There have been a lot of threads on the speedo problem. As mentioned, the heated grips don't have anything to do with it, except...these things almost always manifest themselves in cold weather. My speedos are fine in warm weather, but go crazy everytime the weather turns cold. Could be a problem with the speedo drive dogs or the cable, or it could just be cold weather - especially if the previous owner lubed the cable (which most people agree you are NOT supposed to do). Link to comment
rtp Posted March 28, 2011 Author Share Posted March 28, 2011 Thanks for the replies. I'll be doing a tb synch and changing the belt. When i've got her apart I'll check the cables and connections. Funny it only happens cold...must be shrinkage. Link to comment
Deadboy Posted March 28, 2011 Share Posted March 28, 2011 If a wheel was recently removed, plastic dogs that drive the metal tangs in the hub on the front wheel might not be lined up. Also, they might be rounded or stretched to the point of not working all the time. I had this happen last year after changing a tire. The dealer swapped the cable. Did not work. I pulled the hub off a parts bike we have in the garage and changed it out. Speedo again working. +1 mine did the same thing.... Link to comment
AndyS Posted March 28, 2011 Share Posted March 28, 2011 Hi rtp, as others have mentioned, your speedo is cable driven. It could be kinked or trapped, but i think you are going to find the actual speedo head is goin Kaput if you are seeing what you have described. The cable is driven pegs in the front wheel hub. That directly drives a gear wheel. That gear wheel in turn, drives a cable. That cable turns a disc inside the speedo head (it also drives another small gear in the head to drive the odometer). The speedo needle is magnetically coupled to the cable. if something is going awry to make it read very fast (for a prolonged period), then it is likely to be in this area. Frayed (along with trapped and gunked up)cables can cause noise and erratic cable behaviour (bouncing needle). Check the cable routing. Withdraw the inner drive cable from the outer sheath and clean/inspect them. The outer sheath is secured at its lower end by a countersunk screw into the little gearbox on the left-hand side of the centre of the front wheel. The outer section is clipped midway along its length to a little clip on at the front of the glove box (under the fairing), the top end of the outer is secured to the speedo by means of a collared nut (a real pain to get to.....but possible). Andy Link to comment
rtp Posted March 28, 2011 Author Share Posted March 28, 2011 Andy, I understand now the speedo is cable driven. But. You mention the needle is magnetically coupled to the cable? Could this not be susceptible to interference? I tend to go with the cold weather affecting the gauge as this is when I'm more likely to use the heated grips..But with the grips on, and the speedo jumping seems fishy again. Too crappy to ride right now after all the snow. I'll play with it more when I can ride again. Thanks Link to comment
dirtrider Posted March 28, 2011 Share Posted March 28, 2011 Afternoon RTP The magnetic coupling itself seldom causes any problems. It has fixed magnets that drive the cup. The problems usually arise due to the bearing/bushings that are needed to keep the magnetic drive/driven parts in line and centered & turning freely. A few things that can usually go wrong are: -One is the bearings or bushings running dry of lube so the parts start to drive though the centering bearings and not the magnetic coupling. That changes it from a calibrated slipping magnetic drive to a direct friction drive. (cold weather can make this act up more) -Next is about the same but this involves too much heavy lube that causes the bearings/bushing to try and drive through the thick heavy lube and not he proper magnetic coupling (again this usually happens more in the cold than warm weather). The cause is usually from too much lubrication added to the spedo cable so it works it’s way up the inner cable and into the spedo head. -Another failure mode is just plain worn out bearing and bushings. They get worn so either don’t keep the magnetic cup centered on the drive magnets or don’t spin freely enough so it tends to direct drive through the worn bearings/bushing and not the calibrated slipping magnetic drive. Link to comment
awagnon Posted March 28, 2011 Share Posted March 28, 2011 I believe DirtRider is correct. Most likely the bushing on the back of the speedometer where the cable connects has either dried out or worn out. You can try putting a TINY drop of light oil around the bushing when you have the dash apart. You'll proably need to pull the speedometer head to get access. It often squeals at the same time the needle jumps around and is considered the "squeal of death" because it means the speedo is on its way out. The problem is usually exacerbated by cold weather. Link to comment
AndyS Posted March 29, 2011 Share Posted March 29, 2011 ... You mention the needle is magnetically coupled to the cable? Could this not be susceptible to interference? .... No not in the real world. It would take a huge external influence to significantly effect it. The speedo cable turns a magnet inside a cup, and the eddy currents produced when the magnet rotates, attempts to drag that cup. The cup is attached to the speedo needle and has very limited movement and its movement is harnessed & controlled by a spring. Now if the bearings in the speedo drive are worn out (or you had contamination between the magnet and the disc), the magnet could mechanically drag against the cup, so instead of being linked by eddy currents it becomes friction coupled and would cause the cup (and needle) to move much more quickly. Ultimately destroying the speedo. So, the problem could be worn bearings in the speedo head, it could be contamination (including moisture) inside the instrument. However it definately is not your heated grips. Andy. Link to comment
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