NSR125RR electrical issue - neutral light.. Alain? Anyone?

[ripzay]

Hi all..

Got an issue with the neutral light on an nsr125rr (MY2001)

When the bike isn't running, the neutral light behaves as expected.. Comes on when in neutral.

However - when the bike is running the neutral light comes on both when the bike is in neutral, or the clutch lever is pulled in when in gear, obviously this is wrong, and can make finding neutral with the bike running a bit of a pain in the backside..

Any help would he appreciated, the bike has recently been rebuilt and this is the last niggling issue bar setting the fuelling up properly.

Cheers

Ben
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Current: 2005 KTM SuperDuke 990
Previous: 1996 Suzuki Bandit 600
Previous: 1994 Suzuki GSX-R 400

[alains]

probably the neutral switch or the sub cord damaged
see the pict :
-9 sub cord 32111KBS900 discontinued
-10 switch 35600422023 (~£18)
- 19 washer (12mm) 90402KY4900
- 21 nut 4mm 94001043000S
about the sub cord , you can make one (just copy the old one with a piece of wire and terminals)
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the worst day fishing is better than the best day working

[WD Forte]

Usually these symptoms are due to a blocking diode failing or
being connected up in reverse.
(A wiring diagram may help locate it )
If a cable had broken I doubt the light would work at all
and it sounds like the switch is working too.
____________________
bikers smell of wee

[unitynotsocri...]

If its not a loose cable then it does sound like the neutral selector switch in the gearbox
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nearly a normal tax paying tosser.......with ferrileness suzi100,cg125,cb125scb100n,cb175,cd100,cj250t,kh250,c15,125 bantam,super 6,rickman gs750,xt500,250rs,dt175,lifan125,dolomite1850,metro,Morris220ld,morrisfg,leyland princess,range rover,corsa,vw camper .now struggling with legs. MORE ORDER = MORE CHAOS

[Taught2BCauti...]

What WD Forte said.

Follow the wiring on the wiring diagram for the neutral switch and the clutch switch, and you will find the Diode Pack. On my bike, it looks like a fuse and is mounted in the fuse box, but has 3 pins instead of 2.
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Honda Varadero XL125(V8)
www.TheFutureIsHere.eu

[alains]

i doubt diode has something to say with neutral switch
but in case the pict shows where they are (you can see them Under your seat)
____________________
the worst day fishing is better than the best day working

[WD Forte]

The diode doesnt affect the function of the neutral switch but
is there purely to prevent the symptoms described
ie the neutral light coming on when the clutch is pulled
On some bikes with side stand switches, it's combined with other diodes to act as interlocks.
These create conditions on when and how the engine can be started
( and yes, they can be removed and ignored )
____________________
bikers smell of wee

[Taught2BCauti...]

Looking at the circuit diagram for mine, the wire that connects to the junction of the 2 diodes goes to the earth-side of the Neutral Lamp, and to an input on the CDI unit.

One diode is earthed through the Neutral Switch, the other is earthed through the clutch switch and side-stand switch in series. If this diode were to fail 'closed circuit' (passes current both ways) with the side-stand up - operating the clutch would make the Neutral Lamp come on - but not if the side-stand was down.

OP - does the position of the side-stand affect what is happening?
____________________
Honda Varadero XL125(V8)
www.TheFutureIsHere.eu

[ripzay]

https://www.dropbox.com/s/4qe9wdkbvvl4uos/IMAG0427.jpg?dl=1

Ok.. this table shows what's going on - there's only one error, and i've circled it, i'm going to pull the diodes and test them with the multimeter,i hope it's just one of those and not the wiring loom!

Cheers for the replies guys
____________________
Current: 2005 KTM SuperDuke 990
Previous: 1996 Suzuki Bandit 600
Previous: 1994 Suzuki GSX-R 400

[ripzay]

Diodes are fine. I should add that when we got this bike that the clutch switch was disconnected and the bike would only start on the button if it was in neutral, now the starting behavior is correct, the neutral light appears to act as a 'starter button will work now' light.

Also worth mentioning that almost every connector was taken off the loom when the bike was rebuilt so we could recover the loom in braiding - Going to have to trace the wiring loom I think
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Current: 2005 KTM SuperDuke 990
Previous: 1996 Suzuki Bandit 600
Previous: 1994 Suzuki GSX-R 400

[alains]

get the wiring here
https://www.geneva-racing.ch/~alains/schema_R.jpg
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the worst day fishing is better than the best day working

[skatefreak]

Just a tip., know it sounds obvious but...
Clutch in, knock it all the way down and then up 1/2.
Always done it out of habit and I cant even remember if my 600 has a neutral light?!?! lol

-JVr

[alains]

NSR's are nice and simple bikes , most of italian 2 strokes were built-on like them . So any mito,RS125,etc.. have about the same ignition , power alternator , regulator etc...
if they had the same terminals it should be easy to swap units
____________________
the worst day fishing is better than the best day working