JH600 stalling

[milton]

Our JH600s' stalling problem is probably a multi-faceted problem. In my case, clearly the decompression valve and cam had something to do with its stalling a few month ago. Since those are mechanical parts, subject to constant wear and tear, they'd deteriorate as mileage builds up. The fact that it failed to function normally only after around 10km indicated an inherent design problem nonetheless.

Another possible cause for stalling has just been discovered. It is reported on a Chinese JH600 forum today that the connection mechanism from the ECU module to the circuit board is not reliably designed and easily damaged. The consequence of its failure is again sporadic stalling.

The original report can be found here.

The ECU connects to the circuit board through 2 "spring contacts" in the following picture:


As the bike moves about the springs eventually would become weak or lose adequate contact pressure. One fellow JH600 rider had experienced idential stalling problem as ours, which recovered its previous "as new" condition after he rewired the contact points as follows:


This particular cause of stalling has nothing to do with the ECU programming. It is just a bad mechanical/electrical design.

I will have mine checked (by Dr. Cui) to see if it is part of the stalling problem on my Jialing.

[euphonius]

Dear Milton,

Thanks so much for keeping your eye on the Chinese forums, and sleuthing this out. This seems extremely plausible -- a simple point of failure. Besides vibration and other physical agitation, there could also be corrosion that weakens those two connections. Perhaps they should be soldered together, or at least use some of that dielectric grease.

My KLR650 has been sitting fallow for 18 months, semi-exposed to the weather. On Saturday, apart from just breaking a clutch cable, all my non-ignition electrics failed, for no apparent reason. Both fuses were fine. But the contacts for one of the fuses showed a slight layer of corrosion, perhaps from battery fumes nearby or just humidity. This broke the electrical contact. A quick scrub with a wire brush (loaned by some kindly Hells Angels) and all was well.

Hoping against hope that this JH600 stalling problem can be chalked up to this little design flaw!

cheers!

[Nuhaus]

(loaned by some kindly Hells Angels).

[Lao Jia Hou]

Great find, Milton - thanks!

I concur - I don't think there is a silver bullet solution, except if fired from a Tommy Gun. There are probably several issues at play here. And Jialing should be coming clean with them, and helping us out.

I took my "A" for a run and did a video. Next is to figure out how to upload it withing the GFW (e.g., Youku).

Mr Euph ... "kindly Hells Angels"? An oxymoron? But the real question is ... were they riding HD or Victory? Heh heh.

[MotoKai]

But the contacts for one of the fuses showed a slight layer of corrosion, perhaps from battery fumes nearby or just humidity. This broke the electrical contact. A quick scrub with a wire brush (loaned by some kindly Hells Angels) and all was well.

Or maybe it was the Academics on motorbikes aka "Devils Diciples" (sic)
Now this is all starting to make sense....just didn't know they rode KLRs!

[Lao Jia Hou]

I have done a several videos of my "A" and my "B" and put them on Youku (with the help of a wonderful friend!)

The first one is my 2-wheeled JH600 in my garage. It demonstrates the starting/stall issue. The bike was completely "cold" (had not been started for 24 hours), although my underground garage is probably around 15 degrees Centigrade (a guess).



The second one is me taking my 2-wheeled JH600 out for a run. I am using a GoPro camera mounted sideways on my helmet, so I had to rotate the video 90 degrees (that is why it is tall and narrow).



Coming up ... the "repaired" JH600B.

PS: I profess absolutely zero artistic or technical movie-making ability.

[Lao Jia Hou]

Here is the JH600B.

The "B" was much much worse than my "A". It was essentially undriveable. At first, Jialing tried to brush me off by saying "oh, the "B" does that, some bikes more than others ... we guess you are one of the unlucky ones."

After some foreign growling (and reminding them that I, as a Canadian, wrestle grizzly bears before breakfast), Jialing agreed to "fix" it.

I received the "repaired" bike back a few days ago. It had extensive R&R, including the ECU, cam shaft, decompressor, throttle body, all sensors, air filter, plug, wire, etc. etc. etc. It was given back to me as essentially a new bike.

Here it is in the garage ...



Here it is on the road, October 18 (the GoPro was mounted on my handlebars, so it is a full frame shot) ...



And here it is on the road, October 19 (the GoPro is on my helmet, sideways, so as with my 2-wheeled on-the-road video, it is tall and narrow) ...



Although it is MUCH better than before, it still has a serious stalling issue. The bike is a 2010 with around 6,000 kms.

OK, Jialing, here's the evidence ... how about a response?

[Barry]

Just checked my bike this morning before going to work and I also get this glow-in-the-dark exhaust header in a mere 2-3 minutes from cold start. No stalls though.

The glowing exhaust header is caused due to bad timing and/or running too rich (and the excess fuel is being burnt inside the exhaust)???

[Lao Jia Hou]

The glowing exhaust header is cause due to bad timing and/or running too rich (and the excess fuel is being burnt inside the exhaust)???

Yeah, those were my thoughts also. Or, perhaps, a thin metal in the header? I think it goes away after riding around. I've never checked to see if it recurs after the bike has been ridden and is just sitting, idling (assuming, of course, no stall).

Wait a minute! Maybe the stalling is a "feature!" The stalling automatically cools the header!

Isn't that what software programmers say about "bugs" (that ain't no bug, it's a feature!)

[Barry]

Wait a minute! Maybe the stalling is a "feature!" The stalling automatically cools the header!

Isn't that what software programmers say about "bugs" (that ain't no bug, it's a feature!)

Here (my office) they will either say "Not our bug", "Deferred", "Won't be fixed" or as mentioned "Not a bug (expected behavior)"!!!

So one question is, do the latest models still have this glow in the dark feature?