I know there have been a million posts about charging issues and i have read them all but i can not seem to figure out the problem. I have performed all the test on the charging system and everything appears to come back ok. But once the bike is running for about 20 min thats when i start to have problems.
When i turn the bike on i am getting around 13.5v and it drops to about 13.2 at 5kr pms. Once the bike warms up it will drop down to about 13v and doesnt go much higher than that when i rev to 5k rpm. The longer the bike runs the more the volts drop and after a while ill be at 12.5 and will increase to 12.8 at 5k rpms. The longer the bike runs the more volts i drop, sometimes as low as 12.1-12.4. When i do rev the volts jump up a little to indicate it is charging but at idle it will drop back down.
Everything i have read says that it should run above or around 13.5v at all times.
I have a brand new battery.
The rectifier is only about 4 months old, i have also performed the diode test on the rectifier and that came back showing the rectifier is good.
Testing the stator showed .2ohm on all 3 wires and according to the manual that is correct. Also performed the AC volts test and at 5k rpm it is putting out 50 ac volts which is the correct #.

Ive been stranded too many times now and can not figure out what is the issue that is causing my volts to drop as i ride.

Any ideas or help would be greatly appreciated.

 

Well to be honest my bike does the same thing if I just let it idle. So to combat the problem I just stay above 5k done when I ride around. I do plan on replacing the r/r with a mosfet r/r but that's in the future.

 

did you check the r/r plug and wires for burns, or things that can cause resistance? check the resistance of the yellow wires between the stator and r/r. did you see if the stator winding is shouted to ground?

your r/r may be going out again.

 

I have checked all the plug and wires and everything looks good, i also sprayed the connections with connection cleaner.

This is the rectifier i have now

ACCEL Regulator/Rectifier | ZZ36167 | J&P Cycles

Anyone know of a better one? Maybe the K&L one?

 

Yea check out mosfets. I have only heard good things about them,they do require a bit of modification to the wiring harness but I can walk you through it if you end up going that route. You could also look at replacing the wiring between the r/r and stator with thicker gauge wire you should see a small improvement withthat alone.

 

Here are 2 pictures of the plug that the stator plugs into. It looks like one of the wires has some kind of krimp in it and it is brown at the ends when the wire are supposed to be yellow.

I checked the resistance between the stator and rectifier and it came back ok, but im thinking this could cause the issue.

Let me know what you think

Also how difficult would it be to replace those wire ends and plugs?

 

Anybody have any ideas?

Yesterday i tried just taping up those wires coming from the plug and i ran the bike. For about the first 10 min i was holding steady at 13.5 and around 13.1 at 5k rpms. But after about 20 min its starts to steadliy drop all the way down to 12v and even lower when i rev. I can not figure out what it is and im going crazy not being able to ride.

Any suggestions would be greatly appreciated.

 

Mine is somewhat similar. WHen Im idling its a little dim but when i rev it or am riding the higher rpm i am at the brighter it get(balances out and stays the same at about 4000 Rpm+)

 

did you see any burns inside the connector?

that wire is defiantly an issue, if not THE issue. taping it wont fix it, replace it, you need to anyway. i'd put some new wire, bypassing that connector, and see if it solves you problem.

 

I remeber in my research on my rectifier and coming across a few places where the wire/windings of the stator were breaking down and resulting in what sounds like your issue.
I agree with everyone else, check connections first. I just fixed my friends 636 that had one fried terminal in the r/r harness that was returning the voltage back to regulator.

Check eack one and even if they look kind of ok look for discoloration. Sometimes the female spade terminal is opened too much. I typically would check every connection i have with an ohmeter and anything over .3 would require additional investigation.

On another note, Start the bike up with the seat off and the tank loose. I made afeeder bottle for such prcedures. Check for your 50 volts or so AC voltage while running. Good? ok, now plug in the stator connection, verify 13.5-14 DC or so. Good? ok let the bike get hot and when you see your voltage drop as you have been diconnect the stator plug again and see what ac voltage you have then. If its lower then your stator is breaking down.


As to your question of replacing plugs using sealed male anf female spade connectors and taping them and sealing them will work, if not i actully have a site that i buy universal plugs that i use and they work really well.

Hope this helps. Do you have a good Ammeter?