1999 R1100RS Rough running then dies

[kdhamelmann]

I was riding in light to moderate rain for about 1 hour yesterday and then stopped for gas. The bike had been running perfectly normal. Filled up the tank and took off. After a short time, the bike stuttered then ran normal. Another short time and two long stutters then nothing. As I was pulling over, I popped the clutch and got a brief stutter then totally dead. Would not even cough with the starter. Total distance from the gas stop was 9 miles.

My conclusion was that I bought bad gas. After getting a lift home and recharging the battery, I hit the starter. There was a very brief run then nothing. I drained all the gas and changed the fuel filter. No luck. It won't even cough.

I can hear the fuel pump run when I turn on the ignition but can't tell if I'm getting pressure. When I disconnect the fuel lines, I get a free flow of fuel.

Any ideas are welcome.

Karl

 

[BC1100S]

Have you ever replaced, or had rewired, the HES (Hall Effect Sensor)? You're getting classic symptoms of a failure in this area.

 

[roger 04 rt]

Two possibilities: an in-tank hose rupture or a failed HES.

If you disconnect the top hose (return line) and clamp it off, turn the key on, you should get a strong flow coming out the plastic line coming from the fuel distributor. If there is no flow or a weak flow you probably have an in-tank hose, filter or pump problem.

If not a problem in the tank, it suggests an HES problem. Are you getting a spark when you try to start the bike?

 

[kdhamelmann]

I read about the Hall Effects sensor in the archives and was wondering about it. It sounds more like an "instant dead" problem. My bike coughed and sputtered before dying. It started briefly after I rolled to a stop and again after charging the battery in my garage.

Everything points to a fuel problem. The bike coughed, sputtered, and died a short time after a gas stop. I drained all the gas and changed the fuel filter but it still wouldn't start. Was there still contaminated gas in the fuel lines and throttle bodies? I disassembled the tank and checked everything again. This time the bike started right up!

I have ridden to town and work several times and the bike seems normal. I will have a confidence problem for a while. This is the first time the bike let me down. I still have to go back in and change the fuel strainer on the fuel pump. It split open on the end when I was changing the fuel pump.

So maybe its fixed and maybe it will die again. Can a fuel pump be intermittent? Could the strainer be totally clogged and now that the end is split open the gas can get through?

Karl

 

[AntonLargiader]

If you are on your original HES, I would replace it. The symptoms are close enough.

I think if you had a fuel delivery problem it would not go away.