Stators ? By cptk (Read 3,523 times)

[cptk]

So I was running 100 extra watts in driving lights for about a year then the battery took a cr-p....Go figure Lighting problems on a MC-250B...Any how lights latley have been lookin worse than a candle flickering in the wind....Gut feeling was look at stator...And sure enough #1 and #2 Pole Chared....Not melted just burnt. Tried to clean up gently to no avail...Wires broken and too thin from heat..
Question#1 What happens when you draw too much power from a stator?
Question#2 How much voltage or amperage does the stator on these 250cc bikes put out?
Question #3 Would a second battery hooked up in series help with lighting?
Any Help/Advice or Explenation would be very appreciated....

THANX K.

[Cruiser]

Welcome to Scooter Doc, K. Your scoot was displaying an abnormal amount of charging power for a 250B since you were able to run for a year without killing the battery. I'm assuming that you did not have the driving lights on all the time. I will try to answer your questions to the best of my knowledge.

1. Drawing too much power from a stator will give the same result that you have (discoloration and burning of the windings). However, stators are always generating a maximum of power and unless that power is used by external devices, the stator will run hot because it is trying to dissipate it's own power. The amount of power the stator can generate is determined by the amount of poles, number of windings on the poles, and the strength of the magnets in the flywheel. The regulator/rectifier prevents the stator from overheating by directing the power to the devices on the scoot (lights, battery charging, etc.) and any excess is shunted to ground. So, if you run with a very light electrical load, the regulator/rectifier has to work harder to shunt more power to ground. The regulator/rectifier will limit the amount of power being drawn from the stator. If the R/R shorts, then the stator will overload.

2. Volts X amps = power (watts). Watts is the measure of output power of the stator. I have never seen a published figure for the China scoots, but the Honda Helix which has a similar system is rated around 240 watts. The China clones do not have this much output and some guesstimates are around 150 to 180 watts. Part of the higher output of the Honda is due to the better R/R which can handle the higher output of the better quality stator. The Chinese R/R's have a low output in general and are prone to overheating. Chinese R/R's are generally the cause of poor charging performance and a lot of members have gone to Honda quality replacements to get some improvement. Oregon Motorcycle Parts has made some members happy.

3. You do not want to hook up a second battery in series because this will double your voltage and blow out your headlights and other electrical components. Hooking up in parallel will give you more electrical power, but it is not a cure all as whatever you take out of the batteries has to be replaced by the scoot's charging system which is marginal with just one battery. Using the highest ampere-hour battery that will fit in the scoot will usually give the best results.

How about letting us know a little bit more about yourself and your scoot in the new members section? Again, welcome to the forum.

[cptk]

New stator in and orig. lights as bright as the day she was bought. ( which is saying a lot for these beauties ) Am looking at doing more LED add on's such as blinkers and dash lights. Already have replaced running lights and tail/brake lights, also am running an LED bar across the trunk. Looking for that visibility thing at night ya know....So here is another question for you guys??? If the stator is looking to unload energy, instead of returning it and heating things up/ causing meltdowns and such...Then why are we putting Led's in the bikes which run on less/ not of course mentioning the obvious, brighter lighting. By lessening the amp load doesnt this create more heat/energy for the stator and regulator to displace??? Yes the battery needs a good constant charge but after so much there is no where for this energy to go or am I wrong???

[Cruiser]

In normal operation, you always want to have some reserve output for extra battery charging and any additional accessories you might want to add. The R/R determines how much power will be drawn from the stator. If the stator can put out 300 watts and the R/R can only handle 200 watts, then the stator will have to eat up the rest in the form of heat. If the R/R can output 300 watts and the stator can only deliver 200 watts, then the DC output at the R/R will drop if the scooter's electrical load is over 200 watts. In other words the output will be determined by the weakest link and you should not try to use more than that or you end up with a dead battery. I know it sounds wasteful, but this shunt regulation is what we have and being frugal with the DC usage will ensure that we will have some reserve. Any unused power is shunted by the R/R to ground.

Most of these scoots are limited by the R/R output which means that the full output of the stator is generally not used.

[cptk]

Cruiser,
I would first like to thank you for the ( I would say ) expertise advice..Right now the old battery is getting I believe 15.5 volts back. And of course you are right jrryan when the fan comes on it drops/ but only to like 14.. So this is really where I want it to stay..Especially when it gets hot. 105 in Chico is a little tough to ride in, but ride home is still 75+- 80 at night. So I will go back and check the warden's page for LED's both for dash/ Instruments and blinkers. I have had the faring off and still am not sure where the Instrument lights are but I will figure it out unless you guys have some pics on hand...Thanx Again

[light77]

hi i have a bandit uc 250z. if i put in a brand new battery and it starts, and runs and everything works how ever the battery won't stay charged. so i am wondering bad stator or cdi? how do i test to be sure?

[damin69]

Light77 Welcome to the forum. Well you might want to start your own thread to help with your problem but here are some places to start.
You are in the right place to get help with Charging issues.

scooterdoc.proboards.com/index.cgi?board=electrical&action=display&thread=168

www.thegsresources.com/garage/gs_statorfault.htm