charging issues

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bikerdays

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i have charging issues and need help. my problem is that the max my charging system will keep my battery at is 13.7v but when the bike is idling it drops to 12.4-12.5v i've replaced the stator and the regulator just cuz the bike is an 01 and shit gets old and these results now are what i got. before i could barley get into the 13 volt range. i was wondering is there any test that determines the strength of the magnetic rotor around the stator? if the magnet is starting to lose its polarity and get weak then that might make the charging rate drop at idle. any help?
 
I've never heard of a magnet losing its polarity in a stator system. Even in sleds that strictly run off the stator with no battery. Sleds tend to eat stators up.
 
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Make sure your battery is good. Batteries can develop a sulphate condition and then will not come to the voltage they were designed for. It will crank your bike over as if there is no problem but your charging system sees it differently. This condition can translate to a constant call for charging but will never reach the minimal voltage needed and there will be constant current to the battery. 13.7 vdc on a bike doesn't sound bad to me. The reg./rect. is a shunt type regulator so when it sees its voltage threshold it shunts the current from the stator to the heat sink and dissipates it as heat. This is the reason you hear people say,"Do not jump start your bike from a car that has the engine running" It can toast your reg./rectifier.

Some bikes idle with a lower voltage from the system. The current draw adds up from your running and headlights, fuel injectors, ecu, fuel pump etc. Running any ancillaries?

Is your system failing or are you just concerned with the voltages?

You might go back and do a stator test and ring out the windings to see what they are. There should be no continuity of any winding to ground.

Also you should see no reverse bias continuity from the output of you R/R to ground or the input.

Here is a schematic of a typical R/R setup. Z1 is a zener diode that sets the threshold on transistor Q1. which triggers the gates on SCR's (Silicone Controlled Rectifiers) S1-S3. These SCR's are the shunts that dissipate the output of your stator to ground. Although called the "alternator" in the schematic it is the stator and should not be confused with automobile alternators and that type of technology.

Of course make sure all grounds and connection are good. :cowboy:

RR.jpg
 
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Good call on the battery I just assumed since the stator and regulator had been replaced the battery was new too.
I bought a F150 a few years back for a winter beater and the battery read fine cranked the truck like it was new. Would not start it for anything. New battery and good to go.
 
Yeah I just tested mine yesterday too and it maxes out at about 13.7 at 4-5K. Expected a bit more since my Honda was in the 14s. I've read some people complaining about the weak electrical output for the gen I like I have so it wasn't a surprise.

I know I need a new battery. Cranking power at cold seems to just not get it up to speed well enough so I need to crack the throttle and help her out. Yes I know about the flooding carb issues but I am pretty sure its the battery since if its on the charger it starts right up no fuss. Not to mention it says full on the charger but still seems to lack cranking power and will die very quickly.

Think I will get a trugel. Had that in a VFR a few years ago. Worked great.

Pretty sure its the stock battery too, don't think the guy I got it from ever changed it. :(
 
Motogiro said:
Make sure your battery is good. Batteries can develop a sulphate condition and then will not come to the voltage they were designed for. It will crank your bike over as if there is no problem but your charging system sees it differently. This condition can translate to a constant call for charging but will never reach the minimal voltage needed and there will be constant current to the battery. 13.7 vdc on a bike doesn't sound bad to me. The reg./rect. is a shunt type regulator so when it sees its voltage threshold it shunts the current from the stator to the heat sink and dissipates it as heat. This is the reason you hear people say,"Do not jump start your bike from a car that has the engine running" It can toast your reg./rectifier.

Some bikes idle with a lower voltage from the system. The current draw adds up from your running and headlights, fuel injectors, ecu, fuel pump etc. Running any ancillaries?

Is your system failing or are you just concerned with the voltages?

You might go back and do a stator test and ring out the windings to see what they are. There should be no continuity of any winding to ground.

Also you should see no reverse bias continuity from the output of you R/R to ground or the input.

Here is a schematic of a typical R/R setup. Z1 is a zener diode that sets the threshold on transistor Q1. which triggers the gates on SCR's (Silicone Controlled Rectifiers) S1-S3. These SCR's are the shunts that dissipate the output of your stator to ground. Although called the "alternator" in the schematic it is the stator and should not be confused with automobile alternators and that type of technology.

Of course make sure all grounds and connection are good. :cowboy:

RR.jpg
Click to expand...

my system isn't failing but it does have an annoying misfire often. most of the time in lower rpms. i figure it does that due to the low voltage the coils are getting at idle. no bike should have a charging voltage in the 12 volt range at idle. that means at idle the bike isn't charging. i tested the stator a while back as well the regulator and they both tested good. the stator wasn't grounded at all and the regulator didn't show any thing on the reverse bias test but i replaced the parts anyways with oem parts. i have set a new battery in the bike just to see if the charge went up but it didn't.
 
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