[RESOLVED - bad HES] '02 R1150R can't hold idle

[m_stock10506]

also wanted to test the alternator today, but seeing as my Clymer instructs me to first get the bike to idle at 1400, I can't really do so. Any ideas?

Even at idle, 1050 rpm, the voltmeter should show 13.7-14.0 volts. But just bring the rpm to 2-3,000 rpm and check the voltage there. It should be 13.7-13.8 if the alternator is working. 12.3 volts at idle doesn’t sound right, but test it at higher rpm.

Battery load testing should be done with a battery that is fully charged. If the load test is done when the battery isn’t charged then it isn’t valid.

 

[pauls1150]

I'd think that if the voltage climbs back up after the engine is off, then the alternator/regulator isn't putting out enough, and/or the battery is weak.
And there's a difference between "isn't charged" and "is partially charged"... A load test on a "Suspect" battery may reveal that it is on its last legs, while the test on a "lightly boosted" battery (such as what the FLAPS does) may only indicate "marginal" (or better).

(Speaking of which... my present Yuasa from January 2022 is starting to show symptoms... this would be the shortest-lived one I ever had... )

 

[omega man]

How old is the battery?
OM

 

[wobbleduck1150]

The battery was installed by the previous owner and has no manufacturing info on it, but should be no older than a year. Tested today with a generic battery tester, not a load tester, but got abnormally high resistance and a max capacity of 65%. Gonna look into a new battery.

Even at idle, 1050 rpm, the voltmeter should show 13.7-14.0 volts. But just bring the rpm to 2-3,000 rpm and check the voltage there. It should be 13.7-13.8 if the alternator is working. 12.3 volts at idle doesn’t sound right, but test it at higher rpm.

Battery load testing should be done with a battery that is fully charged. If the load test is done when the battery isn’t charged then it isn’t valid.

My bike "idles" with the needle bouncing around well below 900 RPM, and cuts out if any throttle is applied.

 

[bc1100s]

Have we eliminated the HES as being the issue? Visual check of the wires inside the sheathing?

 

[m_stock10506]

bike "idles" with the needle bouncing around well below 900 RPM, and cuts out if any throttle is applied.

Does this bike run? If it stalls when you apply “any throttle” then are you saying that it idles poorly and won’t run at all above idle?

 

[wobbleduck1150]

Have we eliminated the HES as being the issue? Visual check of the wires inside the sheathing?

I'm planning to open it up tomorrow.

Does this bike run? If it stalls when you apply “any throttle” then are you saying that it idles poorly and won’t run at all above idle?

It doesn't run. It idles very poorly (checked today, it's around 300-400 RPM), dies after ~10 seconds, and won't run at all above idle.

I took the ignition coil (single spark) out today and tested it. Primary resistance is 0.8 ohm and secondary is 7440 ohms. Are these values within spec? I've found conflicting answers so I figured I'd ask you all.

 

[m_stock10506]

It doesn't run. It idles very poorly (checked today, it's around 300-400 RPM), dies after ~10 seconds, and won't run at all above idle.

Was this info posted earlier? This is classic symptom of insufficient fuel delivery. You likely have a cracked fuel hose inside the tank on the fuel pump plate. More than likely the U hose. You have JUST enough fuel getting to the injectors to barely run the bike at idle. As soon as you try to add throttle, there isn't enough fuel and it dies. In spite of the high cost, I recommend using the BMW U hose.

 

[pauls1150]

So far, WD50 hasn't said that he changed out the U-hose. Still highly suspect.

Referring back to the posts about his battery, he hasn't said that he's R&R'd that, either... Still highly suspect.

And yeah, my battery is definitely dying... putting a BMW maintainer on it overnight only resulted in about 9 volts. It still starts and runs (so the alternator works!), but it's a goner.

 

[pauls1150]

ADDENDUM - As I mentioned in another thread, I like to dink around with my stuff.... So I learned that my present BMW Maintainer had the exact same problem as a previous BMW charger: the wires going into the male plug (which then connects to the accessory receptacle on the bike) are clamped to the terminals by a tiny screw, and one of them had worked its way to quite loose, meaning that it wasn't making decent contact between the wire and the terminal, so my old battery was not getting a proper charge. (But it STILL started and ran!) Oh well... Check your plug connectors, folks!
And Valdi - Thanks for the great deal!

 

[wobbleduck1150]

New battery arrived. Made sure it was fully charged and swapped it in -- no difference. The HES wiring appears to have some heat damage near the Motronic, so I will see about getting a new heat-resistant one from EME.

Was this info posted earlier? This is classic symptom of insufficient fuel delivery. You likely have a cracked fuel hose inside the tank on the fuel pump plate. More than likely the U hose. You have JUST enough fuel getting to the injectors to barely run the bike at idle. As soon as you try to add throttle, there isn't enough fuel and it dies. In spite of the high cost, I recommend using the BMW U hose.

I had not previously posted the 300-400 RPM bit, but otherwise my problem is as described in my first post. In post #16 we checked that my fuel pressure is within spec at 41 psi, which is why I haven't changed the U-hose. If I've overlooked something please tell me. I'm really a novice at this kind of stuff.

By turning out the BBSs I can get an idle of almost 1000 RPM, but the end result is always the same with it sputtering out.

I set the TPS voltage to 250 mV; dunno what it was before. I'll leave the throttle stop screws alone for now (they're still sealed), as I don't want to cause any more problems messing with things I'm unsure about.

 

[GTRider]

I set the TPS voltage to 250 mV; dunno what it was before. I'll leave the throttle stop screws alone for now (they're still sealed), as I don't want to cause any more problems messing with things I'm unsure about.

A wise choice! There’s an old adage about suspected carb/FI problems actually being electrical problems, and vice versa. The new HES and wiring may make a difference.

Best,
DeVern

 

[m_stock10506]

set the TPS voltage to 250 mV; dunno what it was before. I'll leave the throttle stop screws alone for now (they're still sealed), as I don't want to cause any more problems messing with things I'm unsure about.

This is wrong. Setting the TPS to 250 mv is part of the process of resetting the throttle stop screws. Eventually, in the procedure, you adjust the TPS to 340 mv. If your stop screws still are set to the factory paint marks, your TPS setting should be 340-380 mv, not 250.

I’m not saying you have to change the U hose no matter what, just check it and go from there. I have read others saying that a fuel pressure reading doesn’t necessarily mean that sufficient fuel is getting to the injectors. A fuel return flow test is supposed to show that. I have never done that myself. Disconnect the return fuel hose, and direct the hose from the pressure regulator side into a container. Crank or run the bike and you should see a pencil sized stream of gas coming from the return hose. This shows that the pressure is sufficient to allow the regulator to return gas to the tank.

 

[pauls1150]

Take off the front engine cover and examine the High-Energy-Spark'n'Spittin' wiring RIGHT THERE AT THE HES - this is the most common failure area, since it's very hot down there. You should also try peeling back that little harness' jacket to get a better view "upstream" of those wires.
This is a common failure of the "wrong insulation used thanks to Germany's EPA" bikes.
The fuel return flow test would be a Very useful point of information... one may not see a teeny split in the U-hose.

see also: https://forums.bmwmoa.org/threads/1999-r1100rt-rain-problems.100503/page-2

 

[omega man]

Take off the front engine cover and examine the High-Energy-Spark'n'Spittin' wiring RIGHT THERE AT THE HES - this is the most common failure area, since it's very hot down there. You should also try peeling back that little harness' jacket to get a better view "upstream" of those wires.
This is a common failure of the "wrong insulation used thanks to Germany's EPA" bikes.
The fuel return flow test would be a Very useful point of information... one may not see a teeny split in the U-hose.

Yeah, may the “field collapse properly”.
OM

 

[wobbleduck1150]

Slapped the new HES in and it runs beautifully now. Thanks to everyone for all the help!

This is wrong. Setting the TPS to 250 mv is part of the process of resetting the throttle stop screws. Eventually, in the procedure, you adjust the TPS to 340 mv. If your stop screws still are set to the factory paint marks, your TPS setting should be 340-380 mv, not 250.

I’m not saying you have to change the U hose no matter what, just check it and go from there. I have read others saying that a fuel pressure reading doesn’t necessarily mean that sufficient fuel is getting to the injectors. A fuel return flow test is supposed to show that. I have never done that myself. Disconnect the return fuel hose, and direct the hose from the pressure regulator side into a container. Crank or run the bike and you should see a pencil sized stream of gas coming from the return hose. This shows that the pressure is sufficient to allow the regulator to return gas to the tank.

Thanks for catching my mistake. I set the TPS to 340 mV and did the return flow test prior to installing the new HES.

 

[bc1100s]

Slapped the new HES in and it runs beautifully now. Thanks to everyone for all the help!

Sometimes the simplest solution is also the easiest.