The ghost of Joe Lucas (Triumph Street Triple)

[pete376403]

Chasing a bit of weirdness in the sons 08 Street Triple. Not charging the battery. Following the usual diagnostic steps (main fuse ok) , stator resistance check (between pairs of wires 1-2, 2-3, 3-1) all spot on at 0.6 ohm. Using Fluke meter BTW. All connectors clean and shiny, no evidence of overheating distress.
At idle on the same pairs of wires *should* be more than 12 volt AC. The actual voltage is about 5v on two pairs and nothing (millivolts) on the third pair. Got another stator from TSS (Ricks Motorsports, Inc).Installed, resistance check is about the same one all three pairs. Voltage at idle (2000 rpm), now 19.2 /19.2 / 0 goes up to about 50 - 60 at 5000 rpm but still only on two phases. Original stator appears ok, no obviously blackened coils

This is before the reg/rect is plugged in so even if it is fried, it cant be affecting things. And when the r/r IS plugged in, battery voltage is 12.2 and does not change with engine speed.

Running out of good ideas here .Cant see how the rotor can be bad if its making volts on two of the phases

Edit - it has a Shindengen R/R, not a Kokusan, so it appears the recall may have been done at some time in the past (before our ownership)

[F5 Dave]

That's weird. Voltage is what I'd expect, but why only on two? Still seems like a good idea to test by plugging in a known good reg. There should be an adapter loom to fit the shin um sh14 or whatever it is called to older bike. My 2011 had the 14 std. Ohh look, what did I keep on my shelf as a spare?
I'll send you a PM.

[jellywrestler]

so while you have metered between coils have you also checked each one to earth?

[pete376403]

so while you have metered between coils have you also checked each one to earth?

Only three wires from stator, it is isolated from ground (delta wired). If any lead to ground is anything but open circuit, that would be a fault. And this is what was measured, both the original stator and the new one.

[jellywrestler]

have you tried an analogue meter? digital ones can be misleading

[F5 Dave]

Thinking some sort of earthing problem on stator mount on sidecover. Try jumper from engine to battery? - Nah, you wouldn't get the starter to operate. . . Curious.

[pete376403]

Problem resolved. When he put the new stator in, the wires ended up wrong side of the bracket/guard and the edge of the rotor cut completed through one wire and damaged insulation on the other pair. Resistance reading of the coils is so low what I was reading was the test lead resistance 0.6 ohm.
A session with the soldering iron and heat shrink has repaired the damage and correct assembly will prevent further occurrence. Testing at the stator leads with engine running give 19 ~ 20 VAC on three pairs at 2000 rising to around 70VAC at 5000. When r/r is connected there is 13.8 VDC at the battery terminals through the rev range.
Thanks for comments / thoughts / offers.

[F5 Dave]

Good to see you solve it. Vexing as both stators had one pole completely out.

[SaferRides]

There's always a reason... Just, a thought, did you check the temperature rating of the heat shrink? Stators can get quite hot.

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[pete376403]

There's always a reason... Just, a thought, did you check the temperature rating of the heat shrink? Stators can get quite hot.

Sent from my SM-G980F using Tapatalk

No and that a good thought. What I used is what I had. Might have to revisit the job one day.