2005 640 Adventure Battery Issue


Hi, I have a new to me 2005 640 Adv. Put a new battery, it died 2 times in the long highway rides. After fully charging it, it shows 12.8 v for example but after firing the bike up, it seems like it is charging the battery +0.5 v. Approx 13.2-3 v. Is this voltage normal for the rectifier? Even on the high revs doesn’t reaches to 14v. Thank you. (I have a spare recritifier btw)

Nurettin 6 years 0 Answers 934 views 0

Answers ( No )

  1. It’s a bit low, but the mistake people make is that amps charge a battery, not volts. But yeah, you could be seeing 13.8

  2. Check the wires going in to the cdi…

  3. Sounds like the battery is ok. If it was me travelling, I’d go to a motorbike garage and get them to test the charge coming from your alternator. You can tell if the rotor coils are damaged (you can also often see the damage). Swapping in a new rectifier might help, but it would be better to trace the problem rather than replace in hope of a fix. Depends how remote you are

  4. Not good mate I’ve done 40,000 on mine and it is a lot more beaten up then yours and not have those issues

  5. This is a common problem of the Adventure. You can check and clean all ground cables and solder the both cables (the red and black) from the rectifier – often the connector is lose, or at least change the connector. If the problem at the end is in the rectifier itself, you can upgrade it with those from MOSFET.

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