JH600 stalling

[td_ref]

Well, I guess I agree with you, my experience in China makes me indeed afraid that nothing much will come out of it.
Most likely somewhere down the line we are going to hit the concrete barrier, but who knows?
Everything we learn till that moment might contribute to the solution.

Frankly speaking I think that at the end it will be us who are pushing the buttons on the mobile device.
That it is a mobile device make things easier though, your damn bikes are really heavy to ship ....

For those of you who are interested, I chalked up a simple diagram of the fuel system on your bikes.
It is not complete, but it gives the idea of what we are chasing.



You can simply break it down to 3 main streams:
1. The fuel supply on the left, which is just supplying the filtered fuel at a constant pressure to the fuel injector,
2. The Air supply on the right, which does the same for clean air,
3. The control in the middle, consisting of the ECU, with input form the sensors, and output to the injector.

"Inside" this ECU is a fuel map, which is basically nothing else then a value of how much the injector sprays for each position of the throttle, at each RPM.
It can be easily visualized by a spreadsheet, or by a 3-D diagram.





The problem on your bikes is most likely in the left lower area (no throttle, low RPM).
Solution should be to increase the fuel-values in that area a bit, to let the injector spray more fuel.
Simple, and ice-cream earned ...

However, there is one catch.
Your bikes are of the newer type fuel controls, where there is a sensor (AFV) mounted in the exhaust, and measuring the quality of the exhaust gasses.
It kind of "overrules" the fuel map by adding or taking off fuel of the whole map to compensate a "bad" mixture.
I need to find a bit more info on this matter.

Ok, I will handle the technical discussion by email and not on this forum, but give an update once there is something new to announce.

E.

OK, not to overwhelm someone, I once "research" into FI technology from a vendor call 光印电喷，the text article is confusing in Chinese. This is so much sensible to me.
Technical is cool.

[euphonius]

....Ok, I will handle the technical discussion by email and not on this forum, but give an update once there is something new to announce.

Great, great stuff, Eric, and surely no need to take this discussion offline unless you are worried about disclosing proprietary stuff from Bosch or AVL or Jialing. But I think all of us who ride the JH600 or are considering one, or just are curious about China's enforced drive toward very tough emissions controls will want to read your findings and ideas.

I've offered before and will offer again: If I can be of use in a concerted "customer feedback" action with Jialing, I stand ready to do so.

This is really getting interesting, and encouraging.

thanks again!

[998S]

td_ref: Don't worry, if I don't explain it to myself in a simple way, I get lost as well ;)

euphonius: The reason I will take it off-line is not so much that is is secret or that we should offend someone, but just that by going around with direct e-mails I can copy people easier.
I simply hate the in-forum email services.
But I promise I will either post copies of emails if it is interesting enough, and surely keep you updated.
I actually sincerely hope that it can be solved rather quickly, with just some limited email exchange.
The longer it takes, the worse it will look for you (and for my icecream...).

E.

[998S]

And for all those who have stalling issues, there might be more going on then you tell us

why-men-shouldnt-write-advice-columns-big.jpg

[Lao Jia Hou]

Update re ECU mapping:

We contacted the Beijing Service Center and this is what we were told:

1) The handheld reader that it uses is strictly a reader that can pull error codes off. It cannot alter any part of the ECU.

2) The Service Center said that it thought that even Jialing's Chongqing factory does not have the proper equipment to modify the ECU.

3) The Service Center said that it believes only Bosch has the capability to modify the ECU (i.e., Jialing never acquired the "mother" programs/equipment from Bosch).

4) The Service Center said that, in its experience, it finds that some ECUs work better than others, even though all ECUs are presumably created equally.

So, it seems as if Jialing puts Bosch ECUs into the JH600s as a complete black-box component without an inherent understanding of what is going on inside of them.

This complicates matters, substantially, as now there is another player on the scene.

One could reasonably argue that Bosch is at fault, for designing/providing an ECU that results in the bike operating with persistent stalling. Another argument is that Jialing, as the marketplace vendor, is responsible to the end consumer (us). Of course, "us" (the little people), do not have much hope in getting Jialing and Bosch to sort this out.

Bottom line appears to be we are up shit-avenue without a kick-starter.

We are going to try and deal with Jialing (Chongqing) later this week.

[998S]

Jialing 1 - Bikers 0

I had a chat with LJH on MSN at 7 this morning (you see how serious we take this).
Although it is not the news we want, it is at least very clear answered, and we know it is not just a matter of hooking things up right now.

As mentioned, LJH (and his wife) will go one step up, and try to contact Jialing direct, to see if anything can be reached there.
I agree with them, the final destination will be Bosch CN.
Most likely we already know the answer, but you never know.

But I guess Bosch CN is run by a German Director.
Is there any German member with us in China, who might want to do some PR?
Perhaps they can do us a personal favor, that might be more successful then ending up with a low positioned Bosch manager and knowing the answer already.

In the meantime, Chinabiker in Austria has the questions for AVL, but I did not hear anything back from him.
Let see what comes out from that.

Last suggestion, as a plan B:
I discussed with LJH the origin of the Jialing engine. He is not sure, mentioned Aprilla, but also the F650 from BMW.
I am surprised that a class A supplier such as Bosch is showing up at all, and I presume it is because it was also on the "original" design the copied.
If so, a visit to the local BMW service centre might be considered, who knows if the ECU can just be hooked up to their instruments?

For the above, if any has a suggestion or even a good contact, kindly ask you to please coordinate with me and LJH.
This to prevent that things are done double, probably shooting ourselves in the foot.

Eric

[998S]

I have one more suggestion for a JH600-owner who is a bit handy.
Try to get to the airfilter, and close it for 1/4 of the filter area.
I presume a sleeve of some paper or carton, with some duct tape will do.

This will reduce the air flow, therefore enriching the mixture.
This is not a lasting solution, and you might experience a power reduction.
But it will show if we are on the right track, as it should reduce or solve the stop-stalling issue.

Would love to hear the results from someone doing this.

E.

[Barry]

I have one more suggestion for a JH600-owner who is a bit handy.
Try to get to the airfilter, and close it for 1/4 of the filter area.
I presume a sleeve of some paper or carton, with some duct tape will do.

This will reduce the air flow, therefore enriching the mixture.
This is not a lasting solution, and you might experience a power reduction.
But it will show if we are on the right track, as it should reduce or solve the stop-stalling issue.

Would love to hear the results from someone doing this.

E.

That's a nightmare part of the JH600, taking it apart is one thing. Putting it back together is a pain in the ass however. But I could give it try since mine is fixed with tie-wraps already, I broke the damn thing when I replaced the filter. I have another new filter as well!

[998S]

Yeah, I heard that from Motokai as well.
You might alternatively close the suction opening in the airbox instead.
Perhaps that is a bit easier to do.

Start with 1/4 closure and see, increase or reduce upon feeling how it goes.

E.

[Barry]

Yeah, I heard that from Motokai as well.
You might alternatively close the suction opening in the airbox instead.
Perhaps that is a bit easier to do.

Start with 1/4 closure and see, increase or reduce upon feeling how it goes.

E.

So just put some tape over the intake opening like displayed in the last picture of post #17 here?