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TobyL
26-05-11, 05:08 PM
Hi,

So here is my little problem:

Sv was eating battery power like no tomorrow not, wanting to turn over or start. Battery replaced and worked for a while but then then started not holding charge again.

Stopping at junctions after a long ride there was a funny smell.

Did some tests on recharge voltage with the bike running having jumped it and found it to be 17.5v at idle and 22v at 5000rpm!!


Having read other threads on the forums tested the R/R and found it to be faulty so replaced with a GSXR one. Also found that the battery had boiled and basically melted under my bum - hence the lovely smell I had been getting.

When replacing the R/R also replaced the wiring so that the output from the R/R goes direct to the battery via a 30Amp fuse on the + ve rather than through the original loom.

New battery on and bike turns over great and starts at the touch of the button no problem. Measured the voltage across the battery when idle and is now a healthy 14.5v but when revved to 5000 rpm drops to between 8 - 10volts.....

I have disconnected the three yellow wires coming from the stator and get about 23volts AC at each at idle and 86v AC across all combinations when revved to 5000rpm.

Resistances between the yellow wires are all 0.08ohms and none have connection to ground.

Tried another R/R from another SV and results are same - 8v at 5000rpm.

I've had all the stator connections off and cleaned with Wd40.

So my question is what is going on, why does my battery voltage drop to 8volts and what is my next course of action.

Also just to add to the fun I am under a time pressure as meant to be going away on it to the IOM TT next week.

Thanks

bones450
27-05-11, 06:42 PM
i've just had problems with my charging and done all the checks you have done and had all the same results apart from one. My problem was the r/r was only outputting 8 volts no matter what the engine speed was, replaced it and all is good now, runs at just over 14 volts. My stator windings a all checked out the same as yours. I would be looking at your r/r, was it new?

Geodude
27-05-11, 06:56 PM
What year/model? Might help with solutions. Mine was down to bad earth.

Biker Biggles
27-05-11, 07:40 PM
What year/model? Might help with solutions. Mine was down to bad earth.

Yes.Do check all your wiring connections,earths and battery terminals before lashing out more money on new parts.

TobyL
27-05-11, 09:29 PM
Right problem seems to be sorted. Not sure what I did to correct it but it is now all good. I get very little change in the voltage over the whole range of revs. Battery is a high output anyway so I'm very happy. All earth points are good. I did all the connections a good going over with contact cleaner and unplugged, re plugged everything I could get at.

Strangest thing now is that I want to get a better touring bike. Perhaps a BMW F800ST.........

TobyL
27-05-11, 09:31 PM
And to answer the above question its an S on a V ('99) plate. I eliminated the R/R as I tried two different ones with the same results.

Thanks to all for suggestions - time to load up, IOM TT races here I come.....

yorkie_chris
27-05-11, 09:44 PM
Could be stator is breaking down under load. Where are you?