New to site and having problems with reg/rec or wiring

Hello I am new to this site, I have been working on an 82 maxim 650 and am having a problem with my regulator/rectifier... I think. When I turn the key the headlight comes on but when I start the bike the headlight turns off. And when I put a meter to the battery terminals and rev the engine the meter reads around 16.5 volts but doesn't drop immediately back down to around 13-14 Volts.
So my question is, do I have a bad reg/rec or possible bad wiring somewhere?
Are there any tests I can do to check
Anything will help at this point. And thanks!!!


Cale

 

your headlight should only come on when you start the bike, and should turn off when you turn the key to the off position.

16.5 volts is WAY too high. it should be in the mid 14's when you rev the motor. youre definitely over charging.

i would start by checking the relays. headlight relay is under the left side panel, starter circuit cut off relay is under the tank towards the seat, and theres another relay under the tank towards the forks, not sure what this one is for. check all three for proper functioning (take the outside case off, visually inspect for corrosion and make sure the tab is able to move back and forth. if that checks out, hook the relay up and start the bike, check to make sure the tab is moving as it should).

 

this should help you a ton:

http://www.scribd.com/doc/45120109/Yama ... Manual-Pt2

(this manual mixed up the locations of the headlight relay and starter circuit cut off relay. headlight is under left side cover, and starter cut off is under tank)

 

http://www.electrosport.com/media/pdf/f ... iagram.pdf

I would first double check your meter. With everything off, and the battery fully trickle charged, what does your meter read? It should be between 12 and 13 V.

If that reading is good, follow the diagram in the link above. If you go to D->Yes->Higher than 14.8V, you'll see that they blame the rectifier/regulator(R/R), however, they will also have you test for a voltage drop between the brown and red wire out of your R/R, because the R/R takes it's voltage measurement off of the brown wire, but charges the battery via the red wire, and resistance in between (from a bad connector or ignition switch) will cause a voltage drop which will over charge the battery.

I found this recently on my Turbo Seca and re-pinned all of the brown and red wire connectors on the bike.

 

all the covers on these relays can be taken off with a small screwdriver, then just a swipe or two with 800 wet/dry sandpaper thru the contacts then follow the coil wires to the outside prongs and a quick touch on a trickle charger or real quick touch on the battery proves the coil part. spray some LPS 1 in there and close it up. if you do all the relays it might save you some grief down the road. then think about the connectors and fuse box.
take a good close look at 3 white wires that come from the alternator to a plug around the starter solenoid, that plug likes to melt

 

Thank you for your replies! I will check the relays and follow the flow chart to check my charging system and get back to you guys.

 

So the headlight relay was corroded inside the cover, so I will need to replace that. I can't find anywhere that sells this individual part though. Does anyone have any suggestions of where to get one?