Hi. Newbie here. I just bought a Kawasaki Vulcan 700 (1985 - redundant to say, I know), and didn't check further into just what was wrong when the previous owner said that the battery wasn't turning the engine over fast enough to start it so he had to get another battery. I didn't know that alternator problems on bikes, or at least this bike, could be an expensive or time consuming project vs. changing an alternator on a car. I guess that is what I deserved buying an 85 for $1,500 with 17,000 miles on it.
Annie way, I checked the voltage at the battery while still in the bike and turned off and it was 12.5v, and then while idling it is 12.1v. So, yes, I suspected a problem. I've pulled the plug on the regulator/rectifier and tested for resistance across the various 6 posts, and get basically nada on all of them - I have ordered a new regulator/rectifier from regulatorrectifier.com which is supposed to be better than OEM for $100.00.
I also have tested the resistance across the three yellow alternator wires, trying the various combinations of two wires at a time, and get about .18 average. I started the engine and ran it at 4000 rpm and tested across the three wires with different combinations and I only get 17.5 - 19.1 volts a/c. I understand it should be between 50-70 volts.
So, if I did things right, I'm guessing that at least my stator, and possibly the rotor, is shot as well as the regulator/rectifier. Am I right? Or, could I still be missing some things? I've read a number of threads on this group to learn some of this, along with my Clymer manual, but I'm not sure I still might be missing something. Pulling the engine or loosening and tilting the engine sounds like a real pain in the butt, or paying someone else to do it appears to be real expensive. I haven't called yet, but I imagine the labor would probably be somewhere around $500.
Thanks for any help you can give!
Last edited by Crisco; 07-10-2009 at 07:03 PM.