Still won't start... Mk2

...
I then decided to check the spark again and found I had an intermittent spark; compared to the previous no spark, this was an improvement but it still wouldn't start. A quick shot of Easy Start up the snorkel and it fired up immediately. Wild rejoicing.
Put the tank on and connected up the fuel and she started up first go and settled to a steady idle. Next thing is to see if she starts in the morning.......

?



Cheers,

Mac

Doesn’t this suggest a fuel problem to you?
 
Doesn’t this suggest a fuel problem to you?

I've had lots of bikes that will sit idling all day long, but touch the throttle and they die.

First one i had in with that problem i changed the fuel pressure regulator, had to be that, didn''t it !!! :D No.

I learnt a lesson.. In all cases since with those symptoms (and there's been a few) it's been the hall sensor.
 
Doesn’t this suggest a fuel problem to you?

Indeed it did Roger, but that doesn't explain the intermittent spark and I'd already followed Steptoe's first step instructions to disconnect the injector hose and electrical plug and found I had a fuel supply to the injector but no signal. I accept that assumptions are dangerous (and often contrary to diagnostic analysis), but as the ignition and injector signal both come from the HES, I took a leap of faith and assumed that the intermittent spark could also cause an intermittent injector operation. This might explain why it started OK on Tuesday night, again yesterday morning and today, but then pops and spits when I went to take it for a spin up the road tonight. I checked the throttle cables are properly seated and they are, so its not that..

Then I read Steptoe's post #23 which is very illuminating; mine doesn't die, but its happy to idle but won't rev, so the symptoms are similar. I have therefore decided to stop buggering about and have ordered a new HES. As pointed out in a number of posts, the one I have is 15 years old and replacing it won't be wasted money; if it cures the problem, I (we?) have found the cause, and if it doesn't, I have a spare good HES to carry with me.

Off to glorious Northumberland on Saturday for a week of beer and seafood, (Robinson's Smokehouse in Craster for the UK's best smoked fish, bar none), so the new HES should be here when we get back and will be fitted pronto.
I'll let you know the result.

Again, my thanks for everybody's input. Its heartening to know that people with far more knowledge and experience than me - including those who make their living from it - are happy to share it freely, and I truly appreciate it.

Cheers,

Mac
 
Mac, Understood. But these bikes tend to split their in-tank hoses giving the start but won’t rev symptom. To confirm good or bad all you have to do is simply measure the return flow.
 
Mac, Understood. But these bikes tend to split their in-tank hoses giving the start but won’t rev symptom. To confirm good or bad all you have to do is simply measure the return flow.

Thanks Roger. I've checked everything else so may as well do the flow check as well.
 
Good evening all,

A little later than planned but I'm pleased to report that the new HES was fitted tonight and the bike started up as usual. Test ride tomorrow to confirm if all is well; watch this space.
For interest, it seems the same Bosch HES is used as a cam position sensor on several German cars and entering the Bosch part number into ebay turned up the exact HES for £115.88 delivered compared to £193 from Motorworks - link below

http://www.ebay.co.uk/usr/rtgroup11?_trksid=p2047675.l2559

Just in case the link doesn't work, it came from:
RTG Automotive
Units 1-4 Northstar Business Park
Leyland PR25 3US

I also replaced the alternator belt while I was in there, so have a spare tucked into the tool roll. This gave me the opportunity of trying to use BMW's joke tensioning system; not sure how you're supposed to access the tensioning system and apply 8Nm of torque to the bolt when the engine is in the bike and the loom and God knows what else is in the way? Common sense prevailed and I resorted to the time honoured technique of levering the alternator up until I could just turn the belt through 90 degrees. Sorted - or so I thought until I tried to get the fuel balance pipe back in place and found that with the new belt on, the alternator doesn't go high enough to get the bloody fuel line QD fitting underneath. Will this torment never cease? Left it for half an hour while I made a brew, during which time the belt had relaxed a little and then I was able to lift the alternator a little more without over-tensioning the belt, and all was good. Must remember to check the belt tensioner after a hundred miles or so when its bedded in.

I also ordered a pair of the stainless clad stick coils from Motorworks -based on the money saved on the HES, it was BOGOF. Having confirmed the HES as the faulty part I know the ones in the bike are OK, but the cladding on the right hand coil looks a little crusty and having lost most of this fabulous summer weather while I've been arsing about with the starter motor/HES/whatever, I figured I might as well change them and add the current ones to my travelling spares kit.

So, with a rebuilt starter motor, new battery, HES, alternator belt and stick coils I hopefully have a more reliable bike and can now get out and enjoy the remains of this glorious summer - only problem is I've spent all the petrol money on parts for the bloody thing!

My thanks again to all for your help.
 
Good evening all,


For interest, it seems the same Bosch HES is used as a cam position sensor on several German cars and entering the Bosch part number into ebay turned up the exact HES for £115.88 delivered compared to £193 from Motorworks - link below

http://www.ebay.co.uk/usr/rtgroup11?_trksid=p2047675.l2559

Just in case the link doesn't work, it came from:
RTG Automotive
Units 1-4 Northstar Business Park
Leyland PR25 3US

.

Hi Mac
As you thought the link does not go straight to the sensor.
Any chance you still have the part number?
Cheers
 
Yes, thats the direct Bosch replacement BUT it just means the same problem is going to come around again. I bought an uprated HES from Sherlocks, bit more expensive but comes with a 3 year (as opposed to 1) guarantee, and he says they have never had one returned. The bins markup is a bit high i agree !
 


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