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When riding into work last Thursday the 11s cut out in the fast lane on the M25 at about 80mph, I managed to coast onto the hard shoulder without too much trouble as it wasn’t that busy. Still scary stuff though!!.

All the electrics were working and the fuel pump was cutting in, but the bike just turned over and over without firing up. I knew what it was as I neglected to change the fuel filter at the last service and had the same problem about a year ago. Anyway to cut a long story short I managed to start the bike after about 20 minutes and rode down to the Lakeside exit where I filled up with petrol. I sat in the petrol station for about ten minutes turning the ignition on and off and starting and stopping the bike several times, on each occasion the bike fired up on the button without hesitation, I then managed to ride it 60 miles back to Colchester without it missing a beat.
I’ve now changed the fuel filter, with the old one being the cause of the problem as I could only just manage to blow through it.
I rode the bike into work the next day on Friday, approx 160 miles round trip, without it missing a beat.
However when I pulled the bike out on Monday this week, it fired up on the button and sat on the drive for 20 seconds before I setoff to the end of the road about 100 feet away, where it stalled and refused to start. I have stripped the bike and found there is petrol getting to both cylinders, but there is no spark on either side. All the electrics are working and the fuel pump is kicking in.
After reading some of the post on here relating to non-starters I have the following questions:

1. Am I right to check the side stand switch, throttle sensor switch and halls sensor first?
2. Could it be the coil, would it suddenly pack in without prior warning?
3. If I disconnect the battery to reset the motronic control unit would this help or maybe compound the problem?
4. Can I just put the bike in gear and have someone apply the rear brake to lock the engine so I can remove the bottom pulley for the halls sensor? They list a special BMW locking tool that has to be applied to the clutch housing in the manual, but obviously I don’t have access to one of these.
5. It has been very wet over the last week so could the fault just be water in the electrics, although I can’t see and rubbed or exposed wiring?

The bike is a 1999 11s with approx 93k on it. I was only thinking the other day how smooth and well it was running after the last service, typical sods law!!

I’ve got the next couple of days off work so will go through all the connectors on the bike with WD40 and check what I’ve mentioned above, but any other thoughts would be greatly appreciated.

I had a similar problem where mine started Ok and ran to warm up, then cut out at the end of the drive on Boxing Day, but mine just seemed to be a low battery - stuck it on the Optimate overnight and it was fine for the Ace Cafe the next morning...

It's a real pain though isn't it?

I feel like I can't rely on just getting my gear on and going out on it...

When I told my pal (who works for a well-known BMW dismantlers, in the North) that I was hoping to do the Land's End-John O'Groats this year, he gave me a pat on the back, a spare Hall sensor and a sympathetic smile. Based on that, It'd be one of the first things I'd check.

When my hall sensor packed in the symtoms showed when the engine was warm and the engine would cut out. You could hear the fuel pump kick in and the engine would turn over but it wouldn't fire up.
Not too expensive to repair. Even cheaper if you are good with the spanners. Good luck.

After spending the whole morning going over the bike I couldn't find anything obvious like corroded wiring/terminals or chaffing on the loom. The only thing I found was the side stand switch looked a bit corroded, so I replaced this with a brand new one, only to find the bike still wouldn't start.

Everything now pointed to the Hall pickup, so a last minute dash to the dealers this afternoon and I purchased a brand new hall switch at only £155 quid!!!!!!!!!!!!. Fitted the switch about and hour ago, turned on the ignition, flicked the kill switch to on, the fuel pump whirred into life, hit the starter and .............. still no spark at either plug.

I've reseated all relays and connectors, sprayed WD40 over most of them as well and cannot find any breaks in the loom.

Totally p****d off with it all.

Anyone have any other ideas or thoughts.

BillyBob wrote:After spending the whole morning going over the bike I couldn't find anything obvious like corroded wiring/terminals or chaffing on the loom. The only thing I found was the side stand switch looked a bit corroded, so I replaced this with a brand new one, only to find the bike still wouldn't start.

Everything now pointed to the Hall pickup, so a last minute dash to the dealers this afternoon and I purchased a brand new hall switch at only £155 quid!!!!!!!!!!!!. Fitted the switch about and hour ago, turned on the ignition, flicked the kill switch to on, the fuel pump whirred into life, hit the starter and .............. still no spark at either plug.

I've reseated all relays and connectors, sprayed WD40 over most of them as well and cannot find any breaks in the loom.

Totally p****d off with it all.

Anyone have any other ideas or thoughts.

Dunno - Have you got any spare HT leads or even 1 that you can try? You could probably even use a car one temporarily if you lift the tank - just to see if you get a spark. It sounds like it still might think it's in gear somehow to me, but then that wouldn't account for it cutting out on the move. You've not got an imobiliser fitted have you I guess. I tried to start the GS after charging the (knackered) battery the other day and it just would not start - so I jumped it off my diesel and 'whoof' off it goes. Not enough amps out the battery is my guess. You could try a jump off a big power source and see I guess. Still wouldn't explain the stall though.

Cheers Jason I'll give the HT leads a go in the morning.

I did think about them, but I thought it would be too much of coincidence for them both to go at the same time, but definitely worth a go. I have kept the battery fully charged via a trickle charger and it’s registering 12.53 volts on an amp meter, so I would have thought I should see some spark, but I'll try and jump it off the car tomorrow as well. The two pin plug that goes into the coil is registering 11.27 volts when the ignition is on, but I've not checked it when cranking the engine over, might be worth a check also.

I have got a datatool alarm/immobiliser fitted, but I have turned it off via the key fob, so when you turn the ignition on the fuel pump kicks straight into life.

I've had enough today, but there's a few more things to check tomorrow

Keep your chin up pal, it's such a downer when you can't sort out what's wrong.

I ended up taking mine to Bemer Bikes in Woodford Green, where they certainly know their onions and the prices are very reasonable too.

You have checked all obvious connections; new side stand switch; new Hall sensor. Fuel pump runs with ignition on. No spark. Fully charged battery? Does the motor crank over? Check the wiring plugs to the motronic unit. Check all fuses - it does them good to be reseated.

Hi Bill...

How have you got on with your bike...interested what the prob was...lso dont like to see another bmw owning essex man bike less..

Cheers Andy

Hey Guys, sorry for the late posting but I've been working away this last week.

Picked the bike up the weekend before last with it all fixed. Turns out it was the ECU that was at fault, quite a rare thing to go wrong I'm informed. Cheers to Darren at Motorworks for sorting out a secondhand one for me and cheers to Reids Motorcycles in Chelmsford who diagnosed and fixed the fault. The guy who runs Reids Motorcycles used to work for Canons BMW in Chelmsford before they moved, so he knows his stuff regarding BMs.
It will take a few runs on the bike before I get out of the mindset of 'is it or isn't it going to let me down again', but at the moment it appears to be running really ........., no I'm not going to say it just in case.

Thanks to all who posted advice on what to check.

Hi BillyBob.

Are Reid's in the old Cannon's building in Chelmsford or just very near it

Useful to know as I am a Newbie and will no doubt need a non dealer expert at some point.

Cheers

Hi Bill...

Glad you got it sorted..and as i also live near..(Rayleigh) am interested about the the guy who works for Reids and where it is....as you obviosly know how much cannons charge for even looking at tyre presure...

Maybe us local lads 1 sunday should have a run out and meet up together and swap some knowledge and information...think on and let me know..

Cheers Andy

Hi Teutonic,

Reids Motorcycles are just round the corner on the same little industrial estate from where Canons used to be in Chelmsford, loads of bikes outside the unit you cant miss it. The guy who owns it knows his stuff and I would definitely recommend it to anyone. He charged me two hours labour (£80) to diagnose the fault and fit the new ECU unit (the unit was £210 second-hand from Motorworks), so all in all not too bad at all.

Quicksilver, I'd be up for a meet up one Sunday morning when the weather gets a bit better, so once the clocks go forward I'll maybe post some possible dates and see what everyone thinks.

Cheers All.

Hi Guys...



Sounds good to me .....Look forward to some warm weather aswell....
Bit feed up of the cold and damp..

Cheers Andy