Bike has died

[Steve.S]

Hi folks ...... my 2003 non ABS R850R has die on me and I am baffled!

I rode 250 glitch free miles on Sunday and came back enthused looking forward to the summer. I decided to use the bike for work on Monday and again there were no issues on the way to work .....on the way home after about 12 miles the bike suddenly died! My first thought was petrol although the bike had only covered 130 miles since filling up so I was pretty confident that it wasn't this. Sure enough after getting my wife to bring me some petrol it still wouldn't go. All of the correct lights come on when the ignition is switched on and the starter turns over. The fuel pump runs for a few seconds as normal. I messed around with the side stand switch and the wiring particularly around the headstock area where I have removed the too tight cable ties. I checked all of the fuses, all to no avail so eventually I had to admit defeat and for the first time in years, hitch a lift home on a breakdown truck!

tonight I took a look again, this time removing a plug to check to see if there is a spark which there was. I now have the tank off but am unsure where to go next. I am guessing it may be fuel related but if so I am surprised that it died so suddenly and has shown absolutely no sign of firing since. As I have said the fuel pump seems to run ok and there is a spark.

Incidentally I acquired the bike towards the end of last year with only 2800 miles on the clock .... ridiculous for a 2003 bike I know. to be fair the bike looks almost brand new and seems in great shape although I realise not using a bike is not great for it. I have put about 800 miles on it over the winter with no problems and intend to put it to good use this summer.

Any suggestions would be gratefully received as I rarely fail to get my bikes going but I fear this may take some finding. My only thought at the moment is maybe a blocked fuel filter but I would be surprised as it gave no hint of a problem until it stopped and I would have expected some hunting or the like before it gave up

Help please!!!!

[Buckster]

Could be the hall sensor. Mine went last year.

[AZBMWRIDER]

Not familiar with the 850 at all, have you checked the fuel line quick disconnects ( if the bike has them ), to see if one may have come apart ??

You could try putting a bit of fuel through the spark plug holes and see if the engine fires then .

[Steve.S]

Thanks guys ..... My 850 is pretty much identical to the 1150 and does have qick disconnects ( and yes I they are the poor quality plastic ones currently .... It's on my to do list to change them). There are connected correctly and have been apart twice today as the tank has been off twice as I have been looking for the issue, so I can rule them out. At the moment I am thinking maybe hall sensor as per Buckster, although at 3000 miles I am surprised it could fail or the wires to deteriorate to that degree. I presume these tell the mototronic at what point to inject fuel. There is a small amount of El inthe pipes when I split the disconnects and there is a spark but maybe the fuel is not getting injected at the right point as a result of the sensor. Am I understanding ths right? I have taken the belt cover off but not pulled the belt and pulley off. What I can see of the wires looks good but I am sure that means nothing. Is there a way of testing if this is the issue. Alternatively is there a wire linked to this circuit that may have been failing due to the earlier removed cable ties?
Thanks for the advice so far guys and apologies for so many questions .... Only I am gutted as the weather is on the up and I just want to ride the damn thing!!!

[EasyBee]

ECU CDI unit gone or it's connections corroded?

[jwagreen]

I had a similar thing happen to me and it was a bad fuel pump fuse. Try putting in a new 10 amp fuse. my 2002 had an original fuse and the plastic cover came off the top of the fuse and the thin wire was corroded. I replaced the fuse and the bike started. i thought the fuse was good at first when i checked it but turns out it was a bad fuse.

[maccraith]

If you have healthy spark on both plugs, it is unlikely to be anything electronic such as hall sensor, computer, ECU or CDI. It is much more likely to be fuel related. By any chance, have you just taken your bike out of winter storage?

If so, and if you did not store it with gas stabilizer in the tank, my guess is that you have finally burned enough fuel to get to the varnish in the bottom of the tank. Once the fuel pump starts pushing that stuff into the throttle bodies and the fuel injectors, it is a matter of miles before the bike stops and won't start.

If this is the case, you are going to have to clean the tank, the throttle bodies and fuel injectors. Sea Foam in the tank may do it. If not, then clean the whole fuel system with Gumout and compressed air.

[Steve.S]

Cheers guys .... I will change the fuse although they all look ok and the pump does run briefly as it should when the ignition is first turned on. As for the fuel it has been used recently and did 250 miles ok on Saturday so I think the tank is ok.

[CycleRob]

Being that the bike died while riding and the bike is about 12 years old it could have ruptured or blown off the short internal hose that connects to the fuel filter. When you turn the key on, listen to the fuel pump and determine if it sounds a little different than before.

[AZBMWRIDER]

In the original post, it says he checked for spark and there was a spark , also when the key is turned on, the fuel pump runs for a few seconds .

Are you getting fuel into the cylinders ???

After you crank the engine with the starter, do you smell raw fuel ???

Are the plugs wet with fuel ??

When you checked for spark, was the spark bluish-white, or reddish-orange ??

[Steve.S]

Yes the pump ran on switching on and there was a spark from both pots checked separately. (bluish white I would say), however there does not seem to be fuel getting through as the plugs are dry. When I split the quick disconnects there is only a vey small trickle from them. If I turn it over with them apart I get no fuel coming out (I assumed that this would generate a flow although I am not sure?

I have had the bike for a few months and it has run fine in the 1000 ish miles I have done in that time. I am at a loss and I need to get it going as I am off to France in a month. The bike has only done 3000 miles and does look like new and has run like new up to now but I do appreciate that time may take its toll on wiring etc. I just want to ride it right now!!!

I hope the above symptoms helps someone to point me in the right direction. A hall sensor is top end of £200 so I don't want to change it unnecessarily

Thanks again for the help so far .... I would be lost without it!

[AZBMWRIDER]

With the fuel line quick disconnects disconnected, you should not get any fuel flow .
Well, it looks like a fuel delivery issue .
The fuel goes from the fuel lines on the right side, to a fuel pressure regulator, then though lines to the injectors .
Only thing I can think of, is to remove the fuel line from an injector, put a clear hose on it and put the hose into a container and then try to start the engine and see if you get any fuel flow when you turn the key on, or while cranking the engine, if you get fuel, it's an injection / engine management issue, if you don't get fuel, the fuel system needs to be checked .

Just one thought, have you looked over the throttle position sensor on the left throttle body to see if there is anything wrong, connector come loose, etc ....

I would also go back to the fuses and check them with a multimeter for continuity, sometimes fuses can fail and not readily be seen, not often though, or swap a known good fuse from another position and put it into the engine management position.

[Steve.S]

I have swoped the fuses early on just in case and they all seemed ok. I guess I need to take your advice with an injector next..... Cheers

[maccraith]

Steve, years ago I owned a BMW store. Every spring we made a small fortune collecting dead bikes off remote highways, taking them back to the shop and cleaning their fuel systems. People would typically store their bike for winter with the remaining fuel in the tank. Or they would fill the tank to full. Over a period of time, the old gasoline would begin to break down and produce varnish - just like wood varnish - in the bottom of the tank. When spring arrived, they would haul out the bike, start it up and ride it. As the gas in the tank dropped to the level where the varnish was, the fuel system would start to suck the varnish into the the carburetor jets and/or the fuel injectors. The result was dead stop and no start. There is virtually nothing you can do but clean the varnish out of the tank and clean the fuel injectors and throttle bodies.

If your tests show that there is no fuel getting to the plugs, clean the varnish out of the fuel system.

[maccraith]

One more thing, Steve. You will also have to change the fuel filter and maybe the fuel pump as well. The varnish will sometimes totally choke off the fuel supply at the filter and/or totally gum up the pump.

Good luck!

[CycleRob]

I agree, the fuel filter most likely is plugged solid. My best guess is still on a ruptured or blown off fuel filter hose, the short, preformed, C shaped one. It is age and its' constant immersion in fuel and fuel vapors, not the odometer reading that kills that hose. The next job is to remove the fuel pump assembly so you can change that way overdue fuel filter -before- you spend any cash on a Hall sensor assembly. If there is a good spark, one of the 2 Hall sensor triggers is working.

[Steve.S]

Thanks Folks ...... I will delve into the innards of the tank on my next day off and hopefully find something untoward! My only reservation is that it has run well up to now with several tanks of fresh fuel recently. I would have expected the filter to clog a little less suddenly. If the pipe has ruptured or come off that would explain the sudden demise more logically to my way of thinking, however my experience of these things is limited. Fingers crossed and I will keep you posted. I will need to get a new filter and sealing ring at the very least. I will wait until the internals are revealed before I get pipes or (God forbid) a new pump. I notice there is a gauze cover listed for the pump too!
Cheers again folks .... Your advice is keeping me sane!!

[riceburner]

Re the fuel hosing rotting - I'm assuming you're in the US Steve.S?

If not then it may be something else - 10% ethanol is still reasonably rare here in Europe.

My 98K miles bike (and the rest!) has no issues relating to the innards of the fuel tank. (and yes - I change the fuel filter at regular intervals)

[Steve.S]

I am in the UK. I don't know if the filter has been replaced since the bike was new so despite the exceptionally low mileage this could be an issue. Looking through the filler cap the tanks looks fine but I appreciate that it is the lower extremities where any issue might be.

[riceburner]

I am in the UK. I don't know if the filter has been replaced since the bike was new so despite the exceptionally low mileage this could be an issue. Looking through the filler cap the tanks looks fine but I appreciate that it is the lower extremities where any issue might be.

Whereabouts?

If you're in the UK then I'd be thinking about something other than rotted fuel hoses as it's an unlikely cause.

Also you don't need to worry about the 'canister' as UK bikes never had them.