I have always heard it should be 44v on the alternator output wires, when revved.And don't discount the possibility of a weak magnet in the rotor. Heat and vibration are magnet killers, and our bikes have plenty of both.If you aren't getting at least 13.2v at the battery, then the battery will never get fully charged.
OK. When testing the stator you need to check between all the different variations of the wires. It is possible you were testing the idle circuit that was only 25 volts. Also, to test the rectifier put your volt meter on the ohms setting or continuity setting. Test between the stator inputs and also the negative and positive wires to make sure you have continuity throughout the rectifier. If there is continuity throughout the rectifier is good, if there is a fault in between any of the wires you have a bad rectifier. It's not too common to have a bad stator unless the rotor is rubbing like my stupid bike keeps doing, but that's another thread.Scottie J
I know next to nothing about these charging systems but your saying you had been in there does make me ask, is it possible one or more of the wires leading out could have been broken or grounded?It's usually best to look at anything that had been recently messed with.
Hey Scottie, I'm not catching what you're saying by checking the V/AC on the idle circuit. I ran the V/AC test similar to that Hitchcock's write-up which is similar to how Kevin has described in other threads on this forum. When monitoring the two violet wires I get single digits at idle, when I bump the throttle up to around 3500 RPM, I'm only getting around 25 V/AC.I did check for continuity through the rectifier, and everything seems to be good there. Used the continuity tester on the grounds as well and all checked out.In a bit I'm going to pull the primary cover off, I'm hoping I just have some slag coating the magnet and everything will be good after a cleaning. I had the primary cover off during regular maintenance not long ago, I can't imagine something would have fouled it up this bad in less than a couple of months, but I'll keep my fingers crossed. I really don't want to have to wait a month for back ordered parts and time to install
Bike stator/alternators are built in phases. If you have 2 wires, it's a 2 phase alternator, 3 wires equals 3 phase. Typically, they have different size coils and put out different amounts of voltage depending on the RPM the motor is turning. While 30 volts isn't crazy high for a stator that should be more than enough to work. If you are getting voltage at the the stator but NOT the battery your rectifier is going to be the culprit, not the alternator. Did you test the rectifier for continuity?Scottie J
I did check for continuity through the rectifier, and everything seems to be good there. Used the continuity tester on the grounds as well and all checked out.
Check this out.http://www.enfieldmotorcycles.com/forum/index.php/topic,490.msg4366.html#msg4366
Thanks Blltrdr! I had read this but could not find it again in my searches. Looks like Kevin said it needs to be at LEAST 50V/AC coming off of the two violet wires, and that even as low as 47 V/AC may not be enough to charge the bike. Thats good to know because the highest I have seen was 35 V/AC with the motor revved up.One thing I did not do was check resistance of the violet wires. I'll do that when I get home from work. I am now sure that the Alternator is bad, but I'd sure like to know why. I know vibration and all, but there's always been good fluid in there, and even though the bike is 12 years old, it has less than 5k miles. During the interum waiting for an alternator, I'm going over the harness with my multimeter as a fine toothed comb. Check any work I've done, patchup and secure any potential abrasion areas for the wires, dielectric grease on all connectors, make sure they're tight and all that good stuff.
Azcatfan:If your sure you need a new alternator, order it from Hitchcocks ! The shipping will be a large number but the item will be in your possession within 3 to 4 days. They airmail everything out side the UK.Neil and Buzzy the Bullet.
Electrical parts wear out period! I wouldn't worry to much on why it wore out unless you think you had done something to perpetuate the problem. These bikes do generate a lot of vibration which can be a killer on electrics. One thing to think about is you are getting voltage, just not enough. Your problem could be that your rotor is not as magnetized as it was when new. An electric motor shop in your area could re-magnetize your rotor for you or you might be able to go online and find a how to video. I would try that before spending the bucks on a new stator. Once you pull your stator and rotor off you can check the rotor by taking a large screw driver and attach it to the rotor and lift it up. If the rotor doesn't stay attached to the driver it needs to be re-magnetized.