So, your bike won't start, before you start changing coils, leads, checking flywheel pick up sensors ( assuming your starter is spinning and your engine is actually turning over)
Try this simple test.
1 unscrew and disconnect the wire from your neutral switch.
2 unplug your side stand switch ( brown and white wires) and link out the female socket with a bit of wire
3 unplug the two top connections from relay 19 and link the two connectors together with a bit of wire ( these are the two bigger connectors of the four on this little grey relay, if you get the wrong two you will blow the 15amp fuse) this also is a useful get you home should this relay fail away from home
( it's the wires your linking out not the relay pins......)4 Now.... Make sure your clutch is adjusted properly and your bike free wheels in gear with the clutch lever pulled in.
5. Put your bike in gear ( any ) and with the clutch lever pulled in, press your start button.
If your bike starts Diode 31 has failed shut ( for want of a better description )
This Diode is a BY253 S3 (The S3 just stands for Silicone 3 amp) I found sellers on eBay that sell these diodes.
The diode is inside the wrapping of the wiring loom crimp connected between the blue and brown / white stripe wire inline with the starter motor area. There are two other diodes in this area of the loom but the one you want is crimped between the blue and brown/white wire.
MAKE SURE YOU FIT THE NEW ONE IN THE SAME DIRECTION! TAKE NOTE OF WHICH SIDE OF THE DIODE THE SILVER STRIPE IS ON AND FIT THE NEW ONE IN THE SAME ORIENTATION!
A diode is like a one way valve or a gate for that matter, it only opens \ lets the flow through in one direction (marked by the silver stripe) get this the wrong way round and it won't work!
Use heat shrink to cover the connections as per the original and tape the loom of wires back up with self amalgamating tape.
JOB DONE!
And a lot cheaper than a new wiring loom!
Hope this helps someone out there
