'96 BMW r850r no run issue

Hello, and thanks in advance for any help, I'm at my wits end. I bought my first BMW used: a 96 r850r. It ran home nice (about 70miles) and ran a few days after I got her home. The only problem was some sort of parasitic draw. The battery would have to be charged then she would run. But then she started dying at stops, I could pop the clutch and keep her running till I got home. One thing though, i pulled the spark plugs just to check them and she hasnt run since.I've bought and installed over $1000 in parts and bought a repair manual. Shes still dead atm...

ok now what ive tried so far... ive installed a new hall effect sensor, new brushes and volt regulator in the alternator, bought a tester to test the hall effect sensor and it seems to light up at the appropriate time. New gel battery. I bought new spark plugs, and new coil, checked the wires and they seem good, I get good bright blue spark. I put in a new fuel pressure regulator, cleaned the fuel injectors, and checked the fuel pump by disconnecting the fuel line and put my finger over the end and turned her on and she shoots fuel pretty good. I bought a new pentiometer or whatever, I call it a tps. Checked voltages and such when I installed it. I checked and corrected valve clearances to the specs in my repair manual. I checked all the fuses and relays and all work fine. All the wiring seems great. As a matter of fact if i spray starting fluid in the air intake the engine roars until there's no more. I checked the air filter and housings and they are all clear. Its just when i try to start her normally she barely runs and dies. I'll choke her and she just barely purrs. I open the throttle she dies, even when the choke is not engaged or at half. If I open the throttle real fast and close it a few times I can tease the rpms up to the red line but I'll get some nasty backfire through the intake into my air filter housing. I dont know why, it doesnt happen when i shoot starting fluid in her. Im just guessing but i want to change the fuel pump, or maybe its the motronic computer, or maybe something else entirely. I just miss riding, and I'm running out of money to dump into her. Please help, any advice would be amazing. I haven't messed with her in a few months so I there might be some info I'm forgetting but I'll cooperate the best I can.

A bad battery quickly comes to my mind. BMW's don't like low voltage batteries. Hook a voltmeter to your battery and try cranking. If the voltage drops below 10 volts, you may have found your problem. If that does not solve your problem, since you say you have spark, pull the injectors and crank, looking for a nice even spray. You might hold a piece of cardboard under the end of the injector. Since you have replaced the HES and the motronic produces a nice fat blue spark, you can rule those out.

Hello, and thanks in advance for any help, I'm at my wits end. I bought my first BMW used: a 96 r850r. It ran home nice (about 70miles) and ran a few days after I got her home. The only problem was some sort of parasitic draw. The battery would have to be charged then she would run. But then she started dying at stops, I could pop the clutch and keep her running till I got home. One thing though, i pulled the spark plugs just to check them and she hasnt run since.I've bought and installed over $1000 in parts and bought a repair manual. Shes still dead atm...

ok now what ive tried so far... ive installed a new hall effect sensor, new brushes and volt regulator in the alternator, bought a tester to test the hall effect sensor and it seems to light up at the appropriate time. New gel battery. I bought new spark plugs, and new coil, checked the wires and they seem good, I get good bright blue spark. I put in a new fuel pressure regulator, cleaned the fuel injectors, and checked the fuel pump by disconnecting the fuel line and put my finger over the end and turned her on and she shoots fuel pretty good. I bought a new pentiometer or whatever, I call it a tps. Checked voltages and such when I installed it. I checked and corrected valve clearances to the specs in my repair manual. I checked all the fuses and relays and all work fine. All the wiring seems great. As a matter of fact if i spray starting fluid in the air intake the engine roars until there's no more. I checked the air filter and housings and they are all clear. Its just when i try to start her normally she barely runs and dies. I'll choke her and she just barely purrs. I open the throttle she dies, even when the choke is not engaged or at half. If I open the throttle real fast and close it a few times I can tease the rpms up to the red line but I'll get some nasty backfire through the intake into my air filter housing. I dont know why, it doesnt happen when i shoot starting fluid in her. Im just guessing but i want to change the fuel pump, or maybe its the motronic computer, or maybe something else entirely. I just miss riding, and I'm running out of money to dump into her. Please help, any advice would be amazing. I haven't messed with her in a few months so I there might be some info I'm forgetting but I'll cooperate the best I can.

Morning Profx

You have a LOT going on with this as well as having thrown a LOT of parts at it that didn't seem to help.

First thing-- You need to quit throwing random parts at it & try to find & isolate the real problem.

If we can believe that is has a nice blue spark (all the time) then your problem is probably fuel or fuel delivery related.

The holding your finger over the hose is not a good fuel pressure/fuel flow test as that doesn't allow it to build much pressure at a decent flow rate.

Your first test (given the above info) should be to do a real fuel pressure/ fuel flow test. Or lacking a proper pressure gauge do a homebrew pressure & flow test by disconnecting the fuel return hose then blocking off the return hose coming from the front (to prevent fuel leaking) then point the RETURN hose coming from the rear into a container, then run the fuel pump (either jump at the fuel pump relay or crank the engine) then look for a pencil sized stream of fuel coming from the rear return hose with the pump running. If not a good solid stream of fuel from the return hose then look for split U shaped high pressure hose inside the tank or, bad fuel pump, or filter blockage, or???

If you have a good fuel return flow then drain the fuel tank & install new (fresh) gasoline as you might have contaminated gasoline in the there now.

You also need to set your new TPS voltage correctly (you can't just bolt a new one on & have it work correctly).

If you have a GOOD blue spark, & good fuel flow with new fresh gasoline, & proper injection on an engine, with proper spark timing, & enough cylinder compression, then it should start & run (what are you missing).

Just keep in mind that the more expensive parts that you randomly throw at it the harder it will be to find the ORIGINAL problem that originally caused it to quit running. With all the new parts you have installed you not only still have the original problem but now also have possible new part install or adjustment issues to deal with.

So make sure you STILL have a bluish colored spark that will easily jump a 3/16" spark gap, that you have a good solid fuel return flow with pump running, that your gasoline isn't contaminated, that you are getting a nice BIG spray from each fuel injector with injectors removed (& pointed into a proper container) & engine cranking, that the engine has enough compression.

Also keep in mind that your choke is NOT A CHOKE, it is ONLY a fast idle device that holds the throttle plates open a little more. I know it says choke on the lever but it isn't a real choke only a fast idle device.

@Roger c: thanks for the input, I was real worried that the moronic was probably the problem, so that gave me more hope. But the battery is new and most of the time I crank it from a jump off my truck. I'll try looking at the injectors again.

@dirtrider: the Oracle indeed sir, thank you. I did read up a lot on the tps setting and I'm pretty sure I got it set right. I'm going to try the fuel pressure test you set up for me and I agree with everything you said about just throwing new parts in all over. I think my mindset was if I replace part x then for sure it's not part x messing everything up. Haha. I will keep y'all informed once I get back around to it. Thank you. Thank you. Thank you... Thank you.

Make sure your throttle cables are sitting correctly. I'd also be a little interested in the state of my internal fuel lines.

https://photos.smugmug.com/2001-R1100S/i-VgnrCwd/0/7fb8478e/M/throttle%20cable-M.jpg

Profs

Did you hook up the fuel lines correctly and not reversed?

My throttle cables are sitting correctly as well as my fuel lines.

Well, depending on the production date, you probably have 1 throttle cable that was a bit problematic and so they changed to a multi-cable set up.

The single cable, for a novice is easy to not get right.

I really suggest you take a hard look at the cable where it goes into the throttle bodies and make sure both sides are fully in the seats and not sitting on the edge on one side.

Someone new to BMW's will pick up numerous tips and tricks in time but having one side not seated is very common and causes the bike to run just terrible and the fix, when found, takes a second or two to correct.

Back in the day, (wheeze) our tech's would use 3M rubber splicing tape to wrap around the cable ends at the TB to insure they didn't pop out after synching.

As DR said, carefully check the return fuel flow.

It just seems that the bike is not synced for idle. Apart from that, check that the magnets did not come off the case, unglued, regarding your "The battery would have to be charged then she would run" issue.

Dan.

Thanks everyone for your input. I'm happy to post she is back up and running. I opened the fuel pump assembly to check it out and right off the bat I saw the hose running from the fuel pump into the metal hose going to the fuel filter was split. I changed the hose and put her back together. Tried starting it and nothing, but I decided to try again today and she coughed then came back to life. Fresh gas and some happy dancing and yelling I rode off.

Dan, what magnets are you referring to?