i bought an 80 ironhead and have been havin a good time with it as a second bike. I have had an ironhead before but it has been awhile. I ordered the hd service manual today but the dealership said it could be awhile before i get it because of the holidays.

The bike did not run when i bought it, but after I did a minor tune up it runs great.
Hear is the problem im having. The battery has died two times and i had to jump start it. The battery is pretty new and it tests good at the auto parts store under the load test. After a charge on the battery charger it tests around 12.5 with my volt meter. While the bike is running it also tests 12.5 with the meter, even when i rev it up.

I tried to polrize it but im not sure i did it right. there are no marks on the generator. So i jumped the positive from the battery to the pole on the generator that is closest to the front tire, it has twoo wires coming off it. the other pole has one tan wire. when i put the jumper on the generator there was a small spark and the generator clicked. i tried it a couple times. still testing at 12.5

So what is next?
thanks

 

If you have a mechanical regulator, flash the bat and gen terminals to polarize it. Check to see if it is charging above 12.5. If not, either the regulator or generator needs work or replacement.

 

The small spark at the battery and and the gentle clunk at the gen indicate that you polarized it correctly. Also on the stockk wire system the A is the lower terminal at the front.

However the A should have two tan wires and the F should have one green wire. On some models the there is just one tan wire at the A because they are combined earlier in the wire system, but there are two in the stock 1980 setup. Full details in this thread ...

Ironhead Charging System Checkout
http://xlforum.net/vbportal/forums/s...ad.php?t=39146

 

yea i didn't describe it right. the a post hd two wires and the f post had one wire.
thanks for posting the info, very good to have especially while i am waiting for the manual

i will start with the 5,6,7,8 tests after christmas and post the results

 

The amps test for the generator is best as it is intuitive, and definitive. If it gives 10 amps i would not bother with the other two.

If the battery loses its charge while the bike sits overnight then the regulator is no good. The one circuit that prevents this from happening is the one that is tested by the test in the thread.

 

i think i need a basic lesson in how to use my multimeter.
i am a decent parts replacer, but no good at electrical stuff

after sitting a couple a days the battery is the same as it was before about 12.5, when cranking it drops to around 10.5 then when it starts back to 12.3-5 range tested at the battery with 12v battery test.

anything more than that i am afraid to say i dont no what setting to use multimeter

for test 7 (again this may be totally wrong, but i connected the leads as said and set tester to (dcv) and put red lead in v input and black in common and increased rpms up and down and the highest it went was .o8v

i did not do test 6 ( my meter says 10amp only) meter has a dc10a setting and a dc10a input jack. Should i use this or no?

test 8 i think reads 2.1 volts

 

i got alittle frustrated and took the gen off the bike and opened it up, one of the brushes is more worn than the other. they do not seem stuck so i lubed them and put it back together. polorized it and retested with the same results. I tested it first with the wires hooked up by mistake (test 7) and the numbers were all over the place

 

Regarding using a multimeter ...

It is very important to get very good contacts. I find that is is quite difficult with the usual pointer probs that come with the meter. What i have done is buy a small package of alligator clips and replace the black probe with a clip. This way i always get a good ground, and can focus on getting a good connection with the red probe.

A better idea is to buy the alligator clips and a second set of pointer probes, and convert both to clips. Then you have one set with pointers and one with clips, and you can choose which to use in each situation.

If you are testing inside a connector use a pointer. Otherwise us a clip whenever possible.

It is worth the time and trouble to do this as it will make your electrical testing life much better, forever.

after sitting a couple a days the battery is the same as it was before about 12.5, when cranking it drops to around 10.5 then when it starts back to 12.3-5 range tested at the battery with 12v battery test

That is a good load test. The battery is good.

It is difficult to know if test #7 failed because the gen is no good, or if it because you are inexperienced with electrical testing and got a bad connection. I would do test #6 as a backup. If it fails this then your procedure on #7 was good. If it passes #6 then the gen is good regardless of anything else.

To do test #6 buy a +-30 amp range ammeter from an auto supply [Princess Auto or Harbor freight have best prices; TSC is more likely to have one in this amp range as it is used on old tractors]. Most stores carry only +-60 amp ammeters. They are OK but more difficult to see a 10 amp reading. Again this is a good purchase that you may use "forever".

This is the best test for a generator as it is intuitive. The gen produces amps and this test measures amps. The two volts tests may indicate if the gen is good or not but i do not know anyone who understands them. The amps test is in the old FSM 99484-78, the two volts tests are in the newer one 99484-85.

Test #9, the bench test, is also a good intuitive test. I believe that it is conclusive but i do not know that with certainty. Lots of guys say it is a good test. Removing the gen from the bike is easy [remove the two electrical and two bolts then wiggle it out]. My little doubt is this: if the test fails then the gen is no good for sure; if the test works i do not know with certainty is that means the gen will work on the bike. Probably does according to most guys.

Also with test #9 it may not work if you hold the third probe on a painted part of the gen body. Works best with a good connection to bare metal.

 

i did test 9 (the bench test and nothing)
i filed the paint down to get good contact on the case
i connected positive
connected negative (with small spark)
touched jumper from - battery to paintless case of gen and nothing

 

is there a rebuild kit for the generator that others have used