Idle problem solved

A late euro3 bike with the headlight on permanently regardless of switch position, can usually be sorted by binning the harness jumper inside the headlight (see pic).
Some had their switch gear blanked off too....just pop the switch button off and flick out the bit of plastic that was put in there to jam it in the on position.
Most management lights staying on with euro 4, if the bike runs well, is usually just a sporadic signal received from the chinese cam sensor when the battery is slightly down on power. The Bosch cam sensors do seem to help with this from what Ive found.
 

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Stu Bodycote said:
A late euro3 bike with the light on permanently regardless of switch position, can usually be sorted by binning the harness jumper inside the headlight (see pic).
Some had their switch gear blanked off too....just pop the switch button off and flick out the bit of plastic that was put in there to jam it in the on position.
Most management lights staying on with euro 4, if the bike runs well, is usually just a sporadic signal received from the chinese cam sensor when the battery is slightly down on power. The Bosch cam sensors do seem to help with this from what Ive found.
Click to expand...
The cam sensor issue is very true.
 
I can’t claim to fully understand the deeper level technical stuff that you guys are involved in, but I am really glad that you are if we ‘the devoted’ are to continue riding our bikes. My running issues (that seem resolved - for now) have almost all revolved around the health of the battery.

Parasitic drain can cause low battery voltage and low voltage, as you identify, causes a whole host of secondary running issues. It seems to my technically challenged brain that it‘s paramount that the battery is healthy at all times. For me, the Shorai lithium (managed through the Shorai BMS) is doing that. Others are using different setups as we know. Whilst I’m really glad you guys are chasing down these issues, I‘m hoping to get away with having changed all dodgy relays/sensors and keeping the battery in tip top condition. Really happy though, that if my plan goes ‘tits up’ that there are technical solutions in place.
 
City Garage said:
The ECU isn't the issue on low voltage. The ECU while a little more technical is basically just a switching and reading hub. Its how the components it trigger react to low voltage. The starter is the biggest draw but it is not dependent on the ECU. The IAC/ICM is controlled by the ECU but if the ECU only gets 11v from the battery at start then the IAC only gets 11v. So if the battery is weak and the draw is excessive when starting the IAC doesn't work well, or it steps slowly is more correct to say. Some of the IAC recover quickly when the bike is started a voltage increases but some freeze or stutter which causes many of the idle issues.

Also unless you have that same battery, each battery will preform different than each other. CCA and capacity make a difference. SO your bike might not start with 11v someone's else will. Also, some of the 961's have the ability to shut off the front headlamp some don't, etc
Click to expand...
@City Garage I wasn't thinking of the electrical load of the IAC, but the mechanical load caused by its operation. Without the IAC fitted the cranking effort is reduced as the cylinders don't get as much air, and the bike turns over noticeably better. @TonyA I believe will confirm this.

By the same process, if a bike has an IAC, and the IAC is "opened" by the ECU during cranking, cranking effort would be higher, and therefore a higher load.
 
Gojuu said:
@City Garage I wasn't thinking of the electrical load of the IAC, but the mechanical load caused by its operation. Without the IAC fitted the cranking effort is reduced as the cylinders don't get as much air, and the bike turns over noticeably better. @TonyA I believe will confirm this.

By the same process, if a bike has an IAC, and the IAC is "opened" by the ECU during cranking, cranking effort would be higher, and therefore a higher load.
Click to expand...
It will change the compression slightly but not enough to really change the cranking effort. Think about the size of the IAC intake hose then look at the size of the air chamber in the crossover. It's no different than cracking the throttle slightly.
 
City Garage said:
It will change the compression slightly but not enough to really change the cranking effort. Think about the size of the IAC intake hose then look at the size of the air chamber in the crossover. It's no different than cracking the throttle slightly.
Click to expand...
@City Garage I would have agreed that it wouldn't be enough to change the cranking effort. However, I've tested exactly what you say - cranking with a slightly open throttle vs closed - and got a different result. Makes a much larger difference than expected.
 
I have for now fitted a small wired switch into the back of the fuse box, so when the bike is standing I can just switch the live to the clocks off. There is no parasitic drain from the clocks, I can leave it for weeks and the battery voltage stays at 12.4 v starts every time. Happy days.
 
DODGY DEN said:
I have for now fitted a small wired switch into the back of the fuse box, so when the bike is standing I can just switch the live to the clocks off. There is no parasitic drain from the clocks, I can leave it for weeks and the battery voltage stays at 12.4 v starts every time. Happy days.
Click to expand...
May as well just wire that switched live to an ignition switched live chap
 
Stephen_Spencer said:
I can’t claim to fully understand the deeper level technical stuff that you guys are involved in, but I am really glad that you are if we ‘the devoted’ are to continue riding our bikes.
Click to expand...

To be honest, I joined this forum to learn. Being at the factory, you were pretty much very limited in what you could do with regards repairs and/or modifications. At times it was immensely frustrating! Taking over service, I saw another side to the 961's, and I enjoyed the challenge I was set, and even though we were very limited with resources, we were still making solid progress..... up until it went belly up.
We'll all get there with it though, the 961's are getting more and more reliable as the niggles are sorted.
 
DODGY DEN said:
I have for now fitted a small wired switch into the back of the fuse box, so when the bike is standing I can just switch the live to the clocks off. There is no parasitic drain from the clocks, I can leave it for weeks and the battery voltage stays at 12.4 v starts every time. Happy days.
Click to expand...

Stu Bodycote said:
May as well just wire that switched live to an ignition switched live chap
Click to expand...
Just wondering, but if I did that, or just a switch as Dodgy did, what sort of saved information would be lost? Pretty sure the time-of-day would have to be reset every time you started the bike, if you wanted it to be correct. Would anything else be lost? I would hope that most of the settings would be saved in non-volatile memory, as they are in the ECU, but I don't have any idea if that's how the instruments are built,

Ken
 
Euro 3 bikes would lose the time and when you shut off the ignition, the rev counter needle will stay in that position until the next ignition on.
Euro 4 bikes are wired a little differently to try and get around this drain. The permanent 12v on their rev counter was instead made an ignition switched live, by wiring it to the ecu shut down relay. They couldn't do the same with the speedo due to the time being lost. Would you rather know the time or go for a ride?
 
lcrken said:
Just wondering, but if I did that, or just a switch as Dodgy did, what sort of saved information would be lost? Pretty sure the time-of-day would have to be reset every time you started the bike, if you wanted it to be correct. Would anything else be lost? I would hope that most of the settings would be saved in non-volatile memory, as they are in the ECU, but I don't have any idea if that's how the instruments are built,

Ken
Click to expand...
The time is the only thing that is lost which would happen if the battery drained down due to parasitic drain. Iam seriously not bothered about the time rather enjoy the ride.
 
A hypothetical ( perhaps stupid) question. What would happen if only one side of the manifold cross tube was blocked off. Would the feed to the other cylinder be enough to keep the RPM higher at startup?
 
Stu Bodycote said:
Euro 3 bikes would lose the time and when you shut off the ignition, the rev counter needle will stay in that position until the next ignition on.
Euro 4 bikes are wired a little differently to try and get around this drain. The permanent 12v on their rev counter was instead made an ignition switched live, by wiring it to the ecu shut down relay. They couldn't do the same with the speedo due to the time being lost. Would you rather know the time or go for a ride?
Click to expand...
The owner who does this will shut the bike off normally first , then the tacho will be at 0 revs . After this , they will remove the power to the instruments via the added switch. Am I missing something here ? Has it been determined that if the gauges are fixed the drain will be nearly nil ? A good gauge will draw less than 1ma .
 
Stu Bodycote said:
Euro 3 bikes would lose the time and when you shut off the ignition, the rev counter needle will stay in that position until the next ignition on.
Euro 4 bikes are wired a little differently to try and get around this drain. The permanent 12v on their rev counter was instead made an ignition switched live, by wiring it to the ecu shut down relay. They couldn't do the same with the speedo due to the time being lost. Would you rather know the time or go for a ride?
Click to expand...
Ok , now I see what I have missed . This problem will occur if you put the tacho to switched power via the keyswitch,. So say bike idles at 1200 rpm , needle will stay at 1200 rpm when key off (not a deal breaker) . If the kill switch does the same , then you snub the engine first and then turn off the key ! :)
 
DODGY DEN said:
I have for now fitted a small wired switch into the back of the fuse box, so when the bike is standing I can just switch the live to the clocks off. There is no parasitic drain from the clocks, I can leave it for weeks and the battery voltage stays at 12.4 v starts every time. Happy days.
Click to expand...
Hi Dodgy , Can you tell us where the switch is located ? Do you have to remove the seat to reach it ? Thanks
 
TonyA said:
The owner who does this will shut the bike off normally first , then the tacho will be at 0 revs . After this , they will remove the power to the instruments via the added switch. Am I missing something here ? Has it been determined that if the gauges are fixed the drain will be nearly nil ? A good gauge will draw less than 1ma .
Click to expand...
To shut the bike off normally is to use the ignition switch, not the kill switch.
My bikes never on charge, with its Motogadget speedo.
 
Stu Bodycote said:
To shut the bike off normally is to use the ignition switch, not the kill switch.
My bikes never on charge, with its Motogadget speedo.
Click to expand...
Just trying to save the guy a few $ . Yes motogadget is very nice ! Would also be nice if VDO worked better. :)
 

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