A friend of mine is having problems with his 2000 Yamaha R6. The bike runs great when the battery is charged, but the problem is that the battery is not charging while he rides. Once the battery runs out of juice he only has a mile until she dies. The R6 is completely stock besides a Yoshi slip on and some LED lights he has on there. He bought it off of his brother who was the original owner, the bike has been well maintained and I believe has close to 20k miles. What does he need to check in order to make sure the battery is continuously being charged?
Thanks
2000 Yamaha R6 possible electrical problem
Started by
braaaaawp88
, Jun 19 2012 09:50 AM
3 replies to this topic
Posted 20 June 2012 - 05:03 PM
Sounds like a bad rectifier. Could also be a bad magneto. The voltage coming from your magneto is AC, the rectifier turns it to DC and limits the voltage. If the rectifier is bad, it wont be long before wires get fried.
Start the bike and use a multimeter to test the current at the negative terminal. That is where the battery charges. You should get a substantial reading on that terminal with the engine running. The positive spits out the power TO the engine. That side should have a good reading with the engine off, slightly higher with engine running.
Clean the terminals. I once bought a new alternator and battery unnecessarily, because I thought they were bad. Turns out the negative side wasnt making good contact.
I'd take it to a shop. I've ripped in to that stuff before and its not fun, not at all. If thats all it is, it shouldnt cost too much.
-Rob R.
Start the bike and use a multimeter to test the current at the negative terminal. That is where the battery charges. You should get a substantial reading on that terminal with the engine running. The positive spits out the power TO the engine. That side should have a good reading with the engine off, slightly higher with engine running.
Clean the terminals. I once bought a new alternator and battery unnecessarily, because I thought they were bad. Turns out the negative side wasnt making good contact.
I'd take it to a shop. I've ripped in to that stuff before and its not fun, not at all. If thats all it is, it shouldnt cost too much.
-Rob R.
Posted 20 June 2012 - 06:14 PM
Rob Reffner, on 20 June 2012 - 05:03 PM, said:
Sounds like a bad rectifier. Could also be a bad magneto. The voltage coming from your magneto is AC, the rectifier turns it to DC and limits the voltage. If the rectifier is bad, it wont be long before wires get fried.
Start the bike and use a multimeter to test the current at the negative terminal. That is where the battery charges. You should get a substantial reading on that terminal with the engine running. The positive spits out the power TO the engine. That side should have a good reading with the engine off, slightly higher with engine running.
Clean the terminals. I once bought a new alternator and battery unnecessarily, because I thought they were bad. Turns out the negative side wasnt making good contact.
I'd take it to a shop. I've ripped in to that stuff before and its not fun, not at all. If thats all it is, it shouldnt cost too much.
-Rob R.
Start the bike and use a multimeter to test the current at the negative terminal. That is where the battery charges. You should get a substantial reading on that terminal with the engine running. The positive spits out the power TO the engine. That side should have a good reading with the engine off, slightly higher with engine running.
Clean the terminals. I once bought a new alternator and battery unnecessarily, because I thought they were bad. Turns out the negative side wasnt making good contact.
I'd take it to a shop. I've ripped in to that stuff before and its not fun, not at all. If thats all it is, it shouldnt cost too much.
-Rob R.
Thanks Rob, I appreciate the response. Were going to charge the battery and then check the negative and positive terminals. Just to clarify because I have so little knowledge of electronics. You're saying that if the negative terminal is not putting out any voltage with the motor running then the rectifier is bad? Or if its not putting out any voltage from the negative terminal it could be either the rectifier or the magneto?
Thanks again
Posted 21 June 2012 - 05:35 PM
Well, I'm not an expert either, by any means.
Just leave everything connected....check the battery's output with the bike off, then with the bike running. It should read slightly higher when running (IE, 12 volts DC off, 14 volts DC running). If it doesnt, then you know the issue. If it does, its probably just a bad battery. Sounds like your battery isnt charging though.
If it is not reading slightly higher when running, it could be the rectifier, but if that were the case you would have fried some wiring long ago I would think. I had it happen on a jetski and BOOM! Instant electrical fire.
Could be a magneto issue, though unlikely. Could be rectifier, though unlikely. May be a bad wire somewhere, a blown fuse (DEFINITELY check all the fuses).
So, to make a long post short: If the voltage is higher when running, then your electrical system is doing its job and its a bad battery (not holding a charge well) or a terminal not making contact. Pour some water/baking soda mixture on the terminals to clean them. If the voltage isnt higher, you have an electrical issue somewhere (magneto issue, rectifier issue, fuse issue, etc). The main point is to see whether or not its even charging the battery. If I were to guess, I bet it is. My guess: Bad contact on the negative terminal. Either way, figuring it out shouldnt take long. Hope thats the case! Let me know how you make out.
-Rob R.
Just leave everything connected....check the battery's output with the bike off, then with the bike running. It should read slightly higher when running (IE, 12 volts DC off, 14 volts DC running). If it doesnt, then you know the issue. If it does, its probably just a bad battery. Sounds like your battery isnt charging though.
If it is not reading slightly higher when running, it could be the rectifier, but if that were the case you would have fried some wiring long ago I would think. I had it happen on a jetski and BOOM! Instant electrical fire.
Could be a magneto issue, though unlikely. Could be rectifier, though unlikely. May be a bad wire somewhere, a blown fuse (DEFINITELY check all the fuses).
So, to make a long post short: If the voltage is higher when running, then your electrical system is doing its job and its a bad battery (not holding a charge well) or a terminal not making contact. Pour some water/baking soda mixture on the terminals to clean them. If the voltage isnt higher, you have an electrical issue somewhere (magneto issue, rectifier issue, fuse issue, etc). The main point is to see whether or not its even charging the battery. If I were to guess, I bet it is. My guess: Bad contact on the negative terminal. Either way, figuring it out shouldnt take long. Hope thats the case! Let me know how you make out.
-Rob R.
