ignition failure 1994 R1100

[beenaround]

I have a 1994 R1100Rs with 44,000 miles on it. The bike started to vibrate a little so I had the valvles set and injectors balanced. It ran well but 75 miles inot the trip home it seemed to begin to vibrate again. I rode the 162 miles home but the next day while riding down the highway the bike died. I pulled off the highway and tried to restart the bike after making sure the engine cut off switch wasn't bumpedand the side stand was flipped up and down a couple of times. The engine would crank but not start. It was noisy so I couldn't hear if the fuel pump was working but after trailering the bike home I hit the starter switch and the bike fired up and idled well. Any suggestions? Beenaround

[duckbubbles]

Hi, beenaround-

The hall effect sensors located on the front of the engine have been known to fail due to heat, then work normally for a while after they cool down, until they fail again. They can sometimes just cut out, like a misfire for a second, too.

 

My cousin, with an R11RT has started carrying a coil around with him. His has failed twice and I assured him that having a spare with him will keep it from ever happening again. But in that case it wouldn't fire at all.

 

There are probably other reasons for this to happen, maybe some of the other people on the site can chime in.

 

Frank

[matanuska]

Sounds like a textbook case of a bad Hall Effect Sensor (HES). Your bike is the right vintage for this type of problem too. Insulation on the HES wiring degraded enough over time to cause loss of all ingition timing signal when the engine got hot. Then while trailering home, it cooled down sufficient to permit restarting.

 

To fix this, a dealer will charge approx $250 for a new HES and likely an equal amount for labor.

 

See this link for a complete description, including diagnosis and repair, to see if it something you might want to fix youreself.

 

http://advwisdom.hogranch.com/Wisdom/oilhead_hall_sensors.pdf

 

DR

[beenaround]

Thanks for the input folks. I ordered a new Hall sensor and coil from boneyard BMW parts. The owner Mike was of the same thought and he spent time explaining how to replace it. Thanks Derek, for the webiste on how to replace/repair the Hall sensor unit, it was excellent!

[bmwmick]

Yours sounds more like a coil problem (unless it was raining when it failed) but Mike IS a good guy to deal with. You can test your coil (usually) by putting a meter acreoss it. Primary should be 0.5 Ohms and the secondary either 13K Ohms or 7.5K Ohms(depending on age of the coil, my 09/95 R1100RT has the older style coil and is 13K Ohms).

I sent you a PM too.

 

Mick