Engine shut off while downshifting

[Swampy]

Originally Posted by ElectricCircus

Great! Now you know what should do with the white one!

That would drive him Crazy. 2LZ has tremors when he sees picks of my "work" quad dirtied up during the season. Cant imagine him being able to sleep knowing there is anything loose on one of his machines......

[2LZ]

Originally Posted by pepperami

Another one who`s bike stalls.

I`ve changed my riding style when I`m on my RX3.
I find mine will stall sometimes when rolling off the throttle after a hard blast at higher revs.
So now as I come down the revs/gears, I blip the throttle once or twice.

Not a cure but at least I don`t end up at the side of the road trying to start it again
I wonder if these bikes are running to lean and the fuel injection/electronic wizardry cant cope at times???

I can't say it's a real problem with mine. It's very rare. maybe it's my riding style. I do blip the throttle when downshifting. I bet out of the 10 months I've owned the RX3, it's only done it maybe twice, three time possibly? It was also only when it wasn't warmed up completely to operating temp. Within the first five minutes or so of run time. I'm not considering it a major issue, just a minor nuisance....but it would be nice to find out why.

[pepperami]

Originally Posted by 2LZ

I can't say it's a real problem with mine. it's only done it maybe twice, three time possibly? It was also only when it wasn't warmed up completely to operating temp. Within the first five minutes or so of run time. I'm not considering it a major issue, just a minor nuisance....but it would be nice to find out why.

Over here it`s -3 degrees in the morning and around +6 or 7 degrees during the day at the moment here in sunny East Anglia in the UK.
Hmm? could it be more of a problem here because the bike cant warm up properly? whaddya think?

[Huck369]

Originally Posted by 2LZ

I still think it has to do with the IAC not keeping up with the sudden closed-throttle demand on occasion. What's causing it not to react is another story. Is it the IAC itself (sticky pintel?) or a sensor or ECM not feeding it the proper info in time?

Mine doesn't die when I let off the throttle....it dies after I stop and it's setting at idle for a few seconds.....

[madsocial]

gremlins...it has to be gremlins.

[2LZ]

Originally Posted by madsocial

gremlins...it has to be gremlins.

You mean after all this all we need to do as add a bell!? ;-)

[JKR]

So, this has happened to me. The bike got bad where it would die coming to a stop multiple times one day and maybe not so much another but to the point it had me worried. Just got worse and worse. I adjusted the valves and the prob went away. It came back after about 1000 miles. Started getting worse again. I did not do the valves correct the first time, bike was probably still to warm. Did the valves again and voila! the problem went away. Chang (my RX3) still OCCASIONALLY will die when coming to a stop. Not very often at all. Did the valves about 3000 miles ago. .08mm, nice little tap to them. Been a great cold weather bike too. All in all, the valves being adjusted solved the dying issue for me. Been a solid ride and love it.

[katflap]

Originally Posted by pepperami

Another one who`s bike stalls.

I`ve changed my riding style when I`m on my RX3.
I find mine will stall sometimes when rolling off the throttle after a hard blast at higher revs.
So now as I come down the revs/gears, I blip the throttle once or twice.

Not a cure but at least I don`t end up at the side of the road trying to start it again
I wonder if these bikes are running to lean and the fuel injection/electronic wizardry cant cope at times???

it is a standard response from the ECU, when certain criteria are met, to cut the injector pulse to zero, thus injecting no fuel.
Completely closing the throttle when travelling at speed will cause this to happen.

Some of the reason for this is to encourage "good" Emissions and fuel economy.

To bring the ECU out of this state, and start injecting fuel ,again, certain criteria has to be met.

2 of these are :-

The RPM dropping below a pre determined figure

The throttle being open more than a pre determined amount


by blipping the throttle you are bringing it out of this "cut-off circuit" thus re introducing fuel into the engine, helping to prevent it from stalling.


Amongst other things, having to do this indicates to me an under developed ECU "maps"

The Delphi mt05 ECU has not been specifically designed for the RX3 but is supplied to motorcycle manufacturers with a basic default "map" setup.
It is then down to the motorcycle manufacturers to develop and change the ECU mapping to suit the motorcycle it is been fitted to.

Getting the correct ECU response to a particular engine at any given time, is a very difficult thing to get right and takes time.

Though I think Zongshen may of spent a lot of time in the workshop doing this, I dont think they spent enough time monitoring the bike in "real life" situations.

As we are unlikely to get ECU "map" updates, we are stuck with trying to work around these glitches.

Some time ago I replaced my thermostat with a higher temperature one. I had a different reason for doing this but have found it had the added benefit of the bike not stalling when coming to a stop and other situations when it would stall inexplicably.

Perhaps a hotter engine is better able to cope with this type of ECU "glitch" and not stall.

DISCAIMER: just my opinion

[2LZ]

Originally Posted by JKR

So, this has happened to me. The bike got bad where it would die coming to a stop multiple times one day and maybe not so much another but to the point it had me worried. Just got worse and worse. I adjusted the valves and the prob went away. It came back after about 1000 miles. Started getting worse again. I did not do the valves correct the first time, bike was probably still to warm. Did the valves again and voila! the problem went away. Chang (my RX3) still OCCASIONALLY will die when coming to a stop. Not very often at all. Did the valves about 3000 miles ago. .08mm, nice little tap to them. Been a great cold weather bike too. All in all, the valves being adjusted solved the dying issue for me. Been a solid ride and love it.

They are extremely likeable bikes and the more I ride it, the more attached I become.

Good to hear a proper valve adjustment did the trick! I know that these (and some of my other bikes) like to loosen battery terminals also. On the RX3, this can cause some weird symptoms, especially since these are ECM driven and injected, just like my Victory's. They can act weird with poor battery connections also. I check mine about every 500 miles on the RX3 so far, just in case.

[madsocial]

See..more and more everyday someone reports this issue. CSC must have seen this thread which lead them to the blog post. However, most of us have tried the majority of their suggestions, if not all to no avail.

I think I'm going to buy a Bell for the Gremlins.

[2LZ]

Originally Posted by madsocial

I think I'm going to buy a Bell for the Gremlins.

As I recall, for the magic forces to work properly, and shed the gremlins from your bike(which make potholes), the bells must be gifted! Better have a chat with your hubby..... ;-)

[Inroads]

^^^ mine has only died maybe 3 or 4 times in 8,000 miles.
FWIW I keep my valve clearance on the loose end of the tolerance.
Might be worth trying to blip the throttle when coming up to a stop as Katflap has discussed for those who are experiencing it.

[2LZ]

Originally Posted by katflap

it is a standard response from the ECU, when certain criteria are met, to cut the injector pulse to zero, thus injecting no fuel.
Completely closing the throttle when travelling at speed will cause this to happen.

Some of the reason for this is to encourage "good" Emissions and fuel economy.

To bring the ECU out of this state, and start injecting fuel ,again, certain criteria has to be met.

2 of these are :-

The RPM dropping below a pre determined figure

The throttle being open more than a pre determined amount


by blipping the throttle you are bringing it out of this "cut-off circuit" thus re introducing fuel into the engine, helping to prevent it from stalling.


Amongst other things, having to do this indicates to me an under developed ECU "maps"

The Delphi mt05 ECU has not been specifically designed for the RX3 but is supplied to motorcycle manufacturers with a basic default "map" setup.
It is then down to the motorcycle manufacturers to develop and change the ECU mapping to suit the motorcycle it is been fitted to.

Getting the correct ECU response to a particular engine at any given time, is a very difficult thing to get right and takes time.

Though I think Zongshen may of spent a lot of time in the workshop doing this, I dont think they spent enough time monitoring the bike in "real life" situations.

As we are unlikely to get ECU "map" updates, we are stuck with trying to work around these glitches.

Some time ago I replaced my thermostat with a higher temperature one. I had a different reason for doing this but have found it had the added benefit of the bike not stalling when coming to a stop and other situations when it would stall inexplicably.

Perhaps a hotter engine is better able to cope with this type of ECU "glitch" and not stall.

DISCAIMER: just my opinion

All good stuff katflap and probably right on, especially when it comes to the "canned mapping" from Delphi.

Question though, since this is a closed loop system after it reaches operating temp, (open loop or choke mode should run on a set mapping), wouldn't then the O2 sensor (along with MAP, etc..) take over and adjust the injector pulse width, as needed, to attempt to reach it's optimum 14.7 to 1 or as close as possible?.....or I wonder if by EPA standards, as you suggest, don't allow that anymore and run them lean, even in closed loop?...which really makes no sense because usually a lean condition creates more HC's. I've never figured that one out. I know way back when I was a CA smog tech, anytime we saw high HC's, they had an air leak somewhere.

It would be interesting if someone could get a sniff at full operating temp at both idle and cruise rpms.

[Sullybiker]

Someone should start collecting some data on this, particularly ambient temperature, that kind of thing.

ECU updates are a common thing, but there's some logistical problems involved, as you can either present the bike to a dealer, or (and I suspect this would be more likely) mail the ECU somewhere to get the firmware flashed.

This problem isn't unheard of on EFI bikes, my own Ninja had a rep for it (I mentioned it up thread) but mine was not affected. I think the cure was a more aggressive idle fuel map.

Interestingly, though I've not ridden an RX3, a common remark is that the bike has excellent fuelling, by no means common on EFI bikes. It would suggest Zong has done a fair bit of work in this area.

[madsocial]

That's a good idea Sullybiker .