Author Topic: Stator failed  (Read 7893 times)

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Offline jm2

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Re: Stator failed
Reply #70 on: 29 August, 2021, 05:08:17 PM
My estimate:-

If open circuit, one failed phase would reduce the available power by a third. I'm unsure how long the bike would run (with the ECU load, fuel pump and headlight alone), I've never measure the real loads.  Two phases down I expect is fatal (no useful charging available).

However, if a coil fails to earth (chassis for the pedantic) which is connected to 0v (or -ve of the battery) then it would depend how far along the chain the fault is from the phase outputs.  Either way I'd expect it to be fatal but you could get a very reduced output from two phases (reduced because that fault is always connected to any working phases via the faulty phase coils).

Of course, an intermittent fault or poor contact to earth brings in a whole new world but ought to be able to be seen by reduced charging ability.

Only do it right - no bodging please.   Keeper of the failed stator list.   John.


Online Art

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Re: Stator failed
Reply #71 on: 29 August, 2021, 05:45:25 PM
For my two penneth the most common stator failure is caused when the insulation of the copper wire coils fail and shorts to ground, normally the failure is less sudden with the insulation breaking down over a period of time. Testing, noting and comparing the charging system output (voltage across the battery terminals at 1,200, 2,500 and 5,000 RPM) at the 4,000 mile (6,000 Km) service intervals should give plenty of warning of any failure waiting to happen. The warning will come by way of a loss of voltage at higher RPM. For example if you get 13.2v at 1,200 RPM, 14.2v at 2,500 RPM and 14.2v at 5,000 RPM all is well and good. If then 4,000 miles later you get 13.2v at 1,200 RPM, 14.2v at 2,500 RPM and a drop to 14v at 5,000 RPM then suspect a charging system fault. Note here that fluctuations in voltage readings or unexpected low voltage readings can be due to the condition of the battery in your multimeter and as jm2 points out charging system failure symptoms can also be caused by a failure in the wiring, connectors, ground etc which is why, before replacing parts willy nilly, you should test the charging system in the logical order of battery, wiring & connectors, stator and last but not least regulator/rectifier.


Offline bobilovsky123

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Re: Stator failed
Reply #72 on: 10 September, 2021, 01:39:47 PM
Hi jm2....As promised to keep you informed, I sent the  stator back to them with a note saying that I wanted a full refund....and that is what they are doing :152: