NC30 electrical fault

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jetman88
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NC30 electrical fault

Post by jetman88 » Wed Jan 23, 2019 6:22 am

Hi all

I've got a problem and have searched and searched before asking but can't seem to find this issue. Lights/indicators etc won't work, temp gauge goes on the spaz to hot (just like it does when grounding the sensor wire to check the gauge) and bike does not run. It will turn over but absolutely no sign of sparking up. Strange thing is on the side stand I can move the bars just a little or even just put gentle weight on the left bar and it will come right, temp gauge drops back down, lights will work and bike will fire up without any issue, however it can easily fall out of this "sweet spot". When I start it, if I can keep the revs up over around 6-7k i can ride it just fine but as soon as revs drop back down, boom, problem kicks in, coughs and splutters and struggles and then dies.

Hoping I've overlooked something simple here and someone can help. Seems like maybe some dodgy wiring is earthing out (could explain the temp gauge??) and causing this? Haven't got to really pulling things apart yet but I've pushed and poked and prodded every piece of wiring I can trying to get a reaction but nothing seems to make a change other than that slight tweak of the handle bars :?

Anybody have an idea what could be causing these symptoms, be it certain components or a section of wiring? Any ideas or help on where to start looking would much appreciated! Track day in 2 weeks need it running :( :pray:

magg
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Re: NC30 electrical fault

Post by magg » Wed Jan 23, 2019 9:28 am

Interesting problem. You might try inspecting the loom earth point in front of the front ignition coil, on the left side of the bike. There are two wires in a common lug. It appears from the wiring diagram the one wire is the front half loom earth and the second, the rear half. Mind you wiring diagrams are not necessarily how the loom is constructed.

You could also use a multimeter to check for 12 volts at various points in the front half of the bike and continuity to the chassis for various earth points.

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NGneer
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Re: NC30 electrical fault

Post by NGneer » Wed Jan 23, 2019 10:00 am

From what you describe it would seem to be an electrical issue one way or the other (short circuit or dodgy earth IMHO).

I would check all your earth points, checking that they are clean and there is a good clean contact to the frame. I have had electrical problems where all the earth points "looked" fine but the problems persisted. All earth cable ends and earthing points on the frame were then cleaned and this has solved a number of issues. Also check that the earth lead itself is in good condition i.e. not breaking down or badly corroded which could stop it working (or at least make it work intermittently).

After that check all the various loom connectors. A good clean with some electrical connector cleaner, visual check of all the cables (looking for damage, corrosion, signs of burning etc). If ok a light squirt of WD40 and check that the connectors go back together properly.

Finally give the whole loom from front to back (including behind the clocks) a good look over for any areas that have rubbed through the protective sleeve and may be causing an intermittent short circuit.

If the bike actually runs as you say it does, it sounds like you just need to find the intermittent electrical gremlin. Work through step by step and you should find it.


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