Gen light off

[dewane]

OK thanks. I found some fuses in my toolbox  (it's a really weird, reall low amp fuse) and checked it out.

Reading is an open circuit. Note: I got the same reading when I disconnected the two spade terminals coming from the brushes. When connected, ohms reading is about 1.5 ohms. I did the paper thing as well - same reading - open circuit.

So...bad rotor? On the good side, I'm doing this before going on a long trip. So, best for it to happen now, I guess.

If so, should I call up Rick from motorrad? Or where can I get a good rotor.

Also, anything unusual to note about removal-replacement? I see from the Haynes book that I need to insert a rod into the rotor bolt hole after removing the bolt?

[Bob_Roller]

To remove the rotor you need a special tool, it's available from Motorrad Elektrik for about $5, don't try inserting a rod or anything else, chances are good it will bend and get caught in there, a real job to get it removed .

Motorrad Elektrik is about the best place for electrical parts here in the US .

If you've done business with Rick Jones, you already know he's a great source of parts and troubleshooting help .

How do your brushes look ?

New brushes are about .75 inches long, so if their on the short side ( when they get to about .25 inches long, they start giving you problems), you may want to consider replacing them now as well .

[dewane]

Rick is a great help for sure, and nice to have somebody around to help to keep these old bikes on the road. Thanks a lot for the info Bob - if you're ever in the SF Bay Area, I owe you a cold soda, or oat soda (my uncle's name for beer  ).

Dewane

[montmil]

Hey guys, if we could get back to my problems, which naturally are the most important things...heh

OK, newbie. Consider us adequately chastised. [smiley=furious3.gif]

[nhmaf]

Umm, when you measured open circuit, you were measuring with the probes on the slip rings (copper rings on front of alternator) with the brushes disconnected or with business cards/plastic sheet inserted between the brushes and the rings, correct?

If your multimeter is no an autoranging type - be sure that you had it set on the LOWEST Ohms setting (usually 200 Ohm full scale) as the alternator is very low resistance (normally).   On out of range display measurement might look to some people like an open circuit..

[Justin B.]

might look to some people like an open circuit..  

Short circuit?

[dewane]

Umm, when you measured open circuit, you were measuring with the probes on the slip rings (copper rings on front of alternator) with the brushes disconnected or with business cards/plastic sheet inserted between the brushes and the rings, correct?

If your multimeter is no an autoranging type - be sure that you had it set on the LOWEST Ohms setting (usually 200 Ohm full scale) as the alternator is very low resistance (normally).   On out of range display measurement might look to some people like an open circuit..

Thanks for the info. I did both actually - tried it with the brushes disconnected, and then with paper between the brushes and the slip rings. I figured it was the same but...well why not?

With the tester, I did it with both settings, which on mine is "Rx10" and "Rx1k" settings. It's an old analog one - I like those better than the digital.

Is there any trick to moving the brushes out of the way? I can't get a good hold on the spring loaded clips that hold them in, especially that one in the rear. The Haynes manual says "see illustration" and then they don't show much of anything in the illustration.

There is open circuit, closed circuit, short circuit. Basically a short circuit means the juice is not going where it should - electricity always takes the shortest route, so it's taking a shorter path. In fact, that's exactly what I did when I did the test by shorting the slip rings together and turning the key, and got the gen light to turn on, as a test.

Which one is this? Open I believe, a short would mean that the circuit is complete, and I don't believe it is.

[Semper Gumby]

I would slip a 3X5 card in between the brushes and the ring...mo rigid!  

[dewane]

Hey, thought I'd follow up on this. I got a new rotor from Rick at Motorrad and installed it. His pilot-puller tool to pull the rotor worked perfect - worth the six bucks or whatever I paid for it. Popped in the new rotor and all is well.

For some reason, it even runs a lot better - i rebuilt the cards and replaced the coil with a Dynacoil, and reset the timing (it was way off), but seems like it just runs a ton better with the new rotor. That...makes no sense. I was getting about 30 mpg before and after all my fixes, I'll be interested when I need to refill what I'm getting now. It will probably be 30.

Keep em on the road!

[nhmaf]

Glad to hear that the R65 is happy again!
Properly tuned up and ridden at relaxed pace, you should get~45 MPG (US Gallon) or so.    I've gotten as high as 49.5 toodling at 50-55 on secondary roads and as low as 39-40 (running ~ 75 MPH steady, loaded, on interstate highway and up&down big hills).