Reply To: Bike cut out – ST7
Have you tried everything below ?
Use E5 only
Go to the battery and test these;
- What volts is the battery at idle (DC)
- What volts is the battery at 5k revs (DC)
Switch the multi meter to 200 to 500v AC next, while the bike is still running, go and find the location of the stator on left side of the engine.
Follow its wire. Disconnect the yellow plug (3 pin yellow plug), now do the following and report back
- Probe the meter and put both “red” and ” black” probes of the meter inside the 3 pin plug in this sequence.
- Pin 1 & Pin 2 = Volts at 5k revs?
- Pin 1 & Pin 3 = Volts at 5K revs?
- Pin3 and Pin 1 = Volts at 5K revs?
It is a three phase stator, so we check all three lines.There is no need to ground the frame or anything like that, we’re just seeing how much volt the stator gives in AC when disconnected (just the yellow plug!)
GV650, GT650, ST7 = Main major electric faults is usually the bad regulators korea ships with the bikes because Hyosung doesn’t make them, but asks another company in Korea to make stators and regulators.
Stators usually survive okay, but please check the wires are not burning hot or cooking up either, usually happens towards the regulator.
I do not mean to scare you off or anything as i’d want you to just go ride the bike but i’ve had instances where i’ve had to send both a new reg and new stator to folks in Scotland (it’s colder up there though???, i digress!)
Also check service history to see if anything about the injectors have been cleaned etc OR go to Halfords or EuroCarParts and only get this item below:
https://www.halfords.com/motoring/engine-oils-and-fluids/fuel-and-oil-additives/wynns-formula-gold-petrol-treatment-500ml-166754.htmlI do not recommend Redex, it isn’t great, despite its raves about it. Its effective on cars mainly.
If you have time and patience, you may strip the tank and (gently!) , remove the fuel pump and make sure its mesh filter isn’t overly clogged from years of debris or past keepers using junk supermarket fuel. We do not need to replace the pump if it is still working but less clogged mesh is good to improve its fuel flow.
A new pump is quite costly , we have to avoid replacing it. It will last as long as its taken care of
I hope i have made sense in this reply
// Meditation doesn't mean you have to sit still....
