JH600 stalling

[MotoKai]

Relay is fine. It's a wiring issue that runs thru 4 sensor-connection points and ends up at the fuel pump.
Somewhere along the way, something's awry: faulty wiring/loose connection, corrosion, bad ground, etc.
-Could be at one of the points or could be between the points-

[MotoKai]

So, it was a sunny day today and I decided even with my bike's potential to break down, I would risk riding to work and enjoy the Spring weather.
And yeah, it broke down again. Same symptoms as listed above.

I had a spare sensor with me, so decided to swap that out. Didn't work.
Played with the fuel pump sensor wiring by hand - just tugging here and there looking for a loose connection. Didn't work.
Slammed down and back up the side stand, thinking maybe that the engine cut-out wire when the stand is down has something to do with it.
Then it dawned on me. Engine cut-out wire! 11 months ago I posted THIS.

I surmised that during the ECU swap, this spliced wire was probably tugged and now loose. This led to the erratic and intermittent cut outs, and the more KMs I added post-ecu swap, the less stable the wire was becoming, causing this to be a progressive issue.

Once the Right Switch Leads Wire Covering was opened, the problem wire was found!.
Frayed wire was repaired and now this CASE IS CLOSED.

[Barry]

Frayed wire was repaired and now this CASE IS CLOSED.

Good to hear the problem is solved just before your holiday! I'm still doubting about where to go, now also thinking about heading to Xi'an instead.

[milton]

Frayed wire was repaired and now this CASE IS CLOSED.

Congratulations on the resolution of your bike problems. I am very happy it is not related to the 3.0 ECU. Now we may have a trip after all.

Wondering what is with Victor's bike. It should not be ECU related.

[euphonius]

Let me chime in with my happiness about this nice outcome. It was not unreasonable for us all to be focusing on the new hardware -- ECU and fresh harness -- as the cause of the problem. But you were right to think "outside the harness", so to speak, and I/we should have done so too. There are indeed several ignition-related wires that are not part of the harness that could contribute to ignition failure, though I'm still a bit baffled why the starter would turn but the fuel pump would not pump. Perhaps the anti-theft circuit cuts juice to the fuel pump and coil/spark plug, but not to the starter motor?

Nah, not going to think about this too much.

Case closed.

cheers

[joker346]

So only me still have a issue with start engine :) Maybe my problem with bad wires too. I hope so. At least gratz to Motokai. Looks like bad journey is over and he can start trip season :)

[Lao Jia Hou]

Sigh ...

My JH600 has been in the hospital for 3 weeks, getting a complete ECU upgrade, etc., etc., etc.

Just got a call from Jialing saying "when we took your bike out, it is still stalling ... a lot ... we've no idea what is causing it."

So, the ECU might not be the ONLY culprit. Kinda confirms what I was feeling before, when a JH600-A rider told me he was also getting stalling.

Edit - just noticed this was my 888th post ... I thought "8" was supposed to be a lucky number? Sigh ... depression-time.

[998S]

That is too bad ... but perhaps easy to fix.
Check with them if they performed the re-set procedure for the TPS (Throttle Position Sensor).
Let them explain then how they did it, and watch ... you will know soon enough if they really have done it.

E.

PS. a TPS reset is necessary EVERY time a NEW ECU is installed.
It gives the ECU the reference point of the throttle "in rest", which is uses as the basis of the fuel map(s).
Not calibrating causes the ECU to operate in a wrong part of the fuel map, and can easily cause these problems.

[Lao Jia Hou]

Thanks for the suggestion. Any idea what the procedure is for the TPS reset? Nothing in the Jialing Service Manual (why am I not surprised?).

I've often done TPS resets on other EFI bikes I've owned/own, and each has a different procedure. E.g., a Victory is ... key on, kill switch off/on, slow twist to WOT, snap back, key off.

Jialing has said ... wait for it ... "we'll try a premium spark plug for the bike and see if that fixes it." Seriously, I am not making this sh1t up.

I'm curious if it is something with my battery (original) and/or stator (prone to failure on these bikes) and/or regulator. I recall reading on another forum (USA made bikes) that EFI can get kinda finicky if the voltage isn't where it should be.

Addendum: During its "rehab", I asked the service center to clean the throttle body when it had the air filter assembly off (I had asked for a new air filter). Assuming it actually did clean the single throttle body, it shouldn't be attributable to this.

[998S]

Yeah, that is the problem with the JL manual.
We tried to look it up when I first worked on the bike of Milton, but failed as well.

Earlier versions of TP sensors have slotted holes, so you can twist the sensor before bolting down.
This is the principle I used (I elonginated the holes for this) on Milton's bike to re-adjust the sensor, so "enriching" the mixture.

However, as the sensor is originally fixed, it should indeed be a setting procedure, either internally (something like you describe), or by means of the external diagnosis software.
Perhaps Milton can chime in with his factory contact?

The voltage story is right, bad batteries can cause strange problems. But you can easily check it with a multimeter:
- check voltage of battery on dead engine
- check voltage of battery on dead engine, with all lights and other consumers on
- check voltage of battery on dead engine, with all consumers on, trying to start it
- check voltage of battery on running engine, at 2.000, 3.000 and 5.000 rpm
Let me know the figures and I will tell you if they are ok.

Eric