'97 R1100R Starting Issues

[wildwillywah]

Last weekend, my wife and I were riding my '97 R1100R and stopped at a rest area. The bike was running fine up to this point (1 hour out).
Upon mounting up, the bike started, but idled erratically and then died when I advanced the throttle. I made four more attempts to start. The bike idled erratically as on the first try, and on the third and fourth try, it would not fire at all.

Fortunately, we were not far out and I trailered the bike back home. The bike has 92K miles , and I had just completed service at the 90K mark. Fuel quantity is not an issue (near full). The fuel pump operates normally (new filter screen & filter at service). I pulled the injectors and checked for spray pattern (no fuel spray). Got spark. Manuel suggests either bad pressure regulator, or motronic unit. Any suggestions?

 

[52184]

Last weekend, my wife and I were riding my '97 R1100R and stopped at a rest area. The bike was running fine up to this point (1 hour out).
Upon mounting up, the bike started, but idled erratically and then died when I advanced the throttle. I made four more attempts to start. The bike idled erratically as on the first try, and on the third and fourth try, it would not fire at all.

Fortunately, we were not far out and I trailered the bike back home. The bike has 92K miles , and I had just completed service at the 90K mark. Fuel quantity is not an issue (near full). The fuel pump operates normally (new filter screen & filter at service). I pulled the injectors and checked for spray pattern (no fuel spray). Got spark. Manuel suggests either bad pressure regulator, or motronic unit. Any suggestions?

I’d pop open the fuel cap and crank the engine to see if you can see/hear fuel splashing in the tank. It’s very possible you have had a fuel line come loose or split, so while the pump is running no fuel is getting to the injectors. Another possibility is failed HES wiring, not uncommon in that vintage of bike, which can result in no fuel flow. FPR and Motronic failures are pretty rare.

Best,
DeVern

 

[senseamidmadness]

If the Hall Effect Sensor hasn't been fixed or replaced already then that's your most likely culprit. When failed the sensor will prevent spark or injector pulses or both. The wiring in the original part is a known factory defect and every one of the three I've taken apart has been failing.

I agree with GTRider that if it's not that, it's something related to fuel supply, and unlikely to be a fuel pressure regulator (though I should say I have replaced the one in my own 97 R850R). It's not unheard of for a little U-shaped rubber fuel line inside the tank, which connects to the fuel filter, to split if it gets old and brittle.

 

[m_stock10506]

I think you have already received the correct answers. Most likely issue is either a fuel hose that came loose, or a split in a hose, most likely the U hose. If you have added quick disconnects you should check them. And, as already said, if you never repaired or replaced the HES wiring, you have to do that, even if it’s not the cause of the problem right now.

 

[gsaddict]

As above check the fuel supply.
After that, the hall sensor is the next suspect.
Especially @ 92k

 

[wildwillywah]

Okay, folks. That's three for the HES. I had replaced all the fuel lines, including the OEM U-hose three services ago.
Does any of you know if the member from Canada still reconditions HES's, or of any company? I haven't checked Beemer Boneyard, yet. But they're usually sold out. Thanks y'all.

 

[pglaves]

Okay, folks. That's three for the HES. I had replaced all the fuel lines, including the OEM U-hose three services ago.
Does any of you know if the member from Canada still reconditions HES's, or of any company? I haven't checked Beemer Boneyard, yet. But they're usually sold out. Thanks y'all.

Yes, "GSAddict" still does rewire HES. He posted the photo of the two type wiring bundles in this very thread, post #5 above. Send him a private message.

 

[wildwillywah]

Thanks, Paul.

 

[33180]

Pop off one of your plug wires or coils and short the threads of the plug to ground while turning the engine over. Got spark? Forget the Hall sensor. Just because you checked the hoses three fuel filter changes ago does not mean a hose has not split or popped off in the meantime. I've been let down that way more than once, both times my fault.

 

[senseamidmadness]

Pop off one of your plug wires or coils and short the threads of the plug to ground while turning the engine over. Got spark? Forget the Hall sensor. Just because you checked the hoses three fuel filter changes ago does not mean a hose has not split or popped off in the meantime. I've been let down that way more than once, both times my fault.

Hall sensor problems can cause either a failure of spark, a failure of fuel injector spray, or both at the same time. It's not guaranteed to be just a spark failure.

 

[wildwillywah]

Thanks again for your suggestions, folks. I checked again to verify that ignition might still be the issue. In accordance with the above recommendations I removed the plugs & grounded. I got spark. Apparently tried to fire it up with the gas cap open. Nada.
While removing the tank to gain access to the HES electrical connection I found one of the fuel quick-disconnectors broken. Strange because I never smelled gas, nor was it apparent when I was wiggling the lines initially to locate the problem.
Anyway...I've got the HES off, boxed, and mailing it off to get upgraded. I really appreciate all your suggestions.

 

[52184]

QDs that won’t break: https://www.beemerboneyard.com/cpcqkdiscon.html

Other useful fueling bits: https://www.beemerboneyard.com/fuliqudise.html

Best,
DeVern

 

[gsaddict]

Only the males need replacing.
This is the updated BMW part - metal
13 53 7 700 800 QUICK-RELEASE COUPLING