Can anyone confirm it's the stator?

[mikesaa309]

Hi all,

Had battery die on me the other day, bumped the bike and when I stopped again it didn't start. Put battery on charge when I got home and battery is holding it's charge. I put it back in the bike and fired it up, revved it to 5k but volatage stayed at 12 odd volts.

I checked stator wires under sprocket cover and getting a 00.7 reading from wire to wire but also same reading from wires to ground. Here's some pics and vid I took: https://photos.app.goo.gl/arXwuVjq7HrSmCXLA

Pretty certain it's the stator but just wanted second opinion from people who know more about the gsx than I do. If it defenitly is the stator, where can I get one from? Wemoto here in the UK has one for £58 but worried it'll be cheap rubbish and not last 5 mins.

[Hooli]

The test is in the manual. It's something like 50-60v AC between any two yellow wires off the stator with the bike running about 5k rpm.

I've had my stator rewound twice, I think it was about £80 a time. The first rewind lasted 40-50k, the second is still going so far.

[Batkwaka]

I was never much good with multimeters and the like so I determined charging issues like this.
Wait until it gets dark and point the headlight at the wall with the engine running. Rev the engine past 4000rpm and watch the light, if it gets brighter the stators are burning out. If it stays the same then the Regulator Rectifier is most likely dead.
The slow discharge of the battery also suggests stators as a dead regulator discharges at a faster rate.

[mikesaa309]

I was never much good with multimeters and the like so I determined charging issues like this.
Wait until it gets dark and point the headlight at the wall with the engine running. Rev the engine past 4000rpm and watch the light, if it gets brighter the stators are burning out. If it stays the same then the Regulator Rectifier is most likely dead.
The slow discharge of the battery also suggests stators as a dead regulator discharges at a faster rate.

Why would the headlight get brighter is the if the stator is burning out? Surely if it get create a charge then it won't get brighter or is it because if it's burning out then power will be low but will have a bit of charging capability left to make the light a bit brighter when revved?

[KiwiCol]

I was never much good with multimeters and the like so I determined charging issues like this.
Wait until it gets dark and point the headlight at the wall with the engine running. Rev the engine past 4000rpm and watch the light, if it gets brighter the stators are burning out. If it stays the same then the Regulator Rectifier is most likely dead.
The slow discharge of the battery also suggests stators as a dead regulator discharges at a faster rate.

Interesting, so what does the light do if everything is ok?

[Batkwaka]

If everything is okay the headlight will again get brighter but you wouldn't be having charging issues.

[mikesaa309]

Okay so I did a AC voltage check from stator wires. They all read 20 volts at idle but go above 60 volts at 5k rpm which is fine according to the manual. However it still showing that from yellow wire to ground, my multimeter is reading 00.5 for all of them which means it's shorting to ground right? So is my stator still knackered even though it's giving out voltages or what is the problem? 

Headlight appears to say the same brightness when revved.

[Hooli]

These are the tests in the workshop manual for the stator & reg/rec.

[Hooli]

I'd be surprised if the stator was shorting to earth & giving voltages, that wouldn't really make sense.

[Batkwaka]

I was never much good with multimeters and the like so I determined charging issues like this.
Wait until it gets dark and point the headlight at the wall with the engine running. Rev the engine past 4000rpm and watch the light, if it gets brighter the stators are burning out. If it stays the same then the Regulator Rectifier is most likely dead.
The slow discharge of the battery also suggests stators as a dead regulator discharges at a faster rate.

Why would the headlight get brighter is the if the stator is burning out? Surely if it get create a charge then it won't get brighter or is it because if it's burning out then power will be low but will have a bit of charging capability left to make the light a bit brighter when revved?

The light gets brighter because the stators are still producing a charge but not enough to compensate for the draw on the battery, usually resulting in that slow discharge whereas a Dead regulator Stops charging completely and dies quite quickly.

[mikesaa309]

I'd be surprised if the stator was shorting to earth & giving voltages, that wouldn't really make sense.

Definitely giving AC voltage reading and they all go to above 60v AC at 5k rpm right up to 70-80v but is shorting to earth. I found this website: shorturl.at/dfvD9

Last line reads: "If you get proper AC voltage and the stator is not grounded (no light) the stator and rotor are good. At this point you can assume the problem is either a bad connection between the regulator and the battery or the regulator is bad"

So in the process of testing the reg/rec but started raining so had to abort mission for the time being and was getting late in the evening. Pain in the backside to get to was hoping I could get it out by taking side panels off albeit fiddly but nope gotta take the rear cowl off near enough Might not even be the reg/rec but might as well test it before messing about replacing the stator but just odd that it's giving voltage read out just fine but shorting to earth.

[KiwiCol]

You've not got a blown fuse have you?   

Mike, I had a look at the pic's in the link.  I'm not fully conversant with that model multimeter, but I think to measure ac you need to put the red plug into the other socket, else you'll get erroneous readings, could be wrong (again)

[froudy]

Sometimes it is worth popping the stator cover off and checking the stator. Burnt coil windings are usually evident and easy to spot...

[Batkwaka]

Okay so I did a AC voltage check from stator wires. They all read 20 volts at idle but go above 60 volts at 5k rpm which is fine according to the manual. However it still showing that from yellow wire to ground, my multimeter is reading 00.5 for all of them which means it's shorting to ground right? So is my stator still knackered even though it's giving out voltages or what is the problem? 

Headlight appears to say the same brightness when revved.

From all the time I spent on the Katana 1100 electrics, I would definitely say the Reg/Rectifier has gone.
Another way to check the reg/Rectifier is by heat, if the charge isn't going to the battery it is going into the Reg/Rec heatsink and should get uncomfortably warm.

[grog]

Mate, if its shorting to earth, insulation gone, faulty stator.