Totally Baffled...Coil problems..or is it?

Rotaxmaxracer

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I have a 1200GS 2006 model that has covered 58000 - and due to go on a NC500 tour, leaving tomorrow morning! Bike had started misfiring so followed Bendy Toy's tips and popped off the coils one by one. Turned out to be the RH secondary coil that was playing up as the LH pipe gets red hot and the RH you can take hold of.

Ordered one of the new type shiny secondary RH coil from Motorworks, along with a new primary - just as a backup being interchangeable.

Just arrived via DPD - fitted the new coil and...nothing, the pipe is still cold and only running on one?

I have done the obvious like changing the spark plug for a second hand one that I had, but also still nothing. The wiring all seems to be OK, but not sure where to go from here.

Does anyone have any ideas as my wife has started the packing :blast

Many thanks

Paul
Rotaxmaxracer
 
And just to make things even more confusing...I had a silly thought to disconnect the secondary coils and just connect both primaries - guess what same result, not firing on the RH pot at all it would seem as the headers are stone cold. Can't be the coil packed as both are brand new and of the latest variety.

Fuelling...or something else do you think? Plugs look wet when they come out so I guess something is getting through
 
If you had the secondaries disconnected and the RH cylinder didn't fire at all then it's not the secondary at fault - it's the primary. It would still fire on the RH side with a failed secondary - not sure whether that's the case with a failed primary.

Just because you have bought new coil packs doesn't guarantee they're good. Swap the LH primary over to the RH side and see if the RH then fires and LH doesn't. Then change the RH primary plug and see if that helps.

Are you sure it's ignition-related? Do the plugs on the RH cylinder get wet with unburned fuel? If not, it could be a fuel problem not an ignition one. Check wiring to the injector, try swapping injectors side to side etc.

Edit; Sorry - just re-read your last post and you are getting fuel through. My money would be on the RH primary coil or plug.
 
If you had the secondaries disconnected and the RH cylinder didn't fire at all then it's not the secondary at fault - it's the primary. It would still fire on the RH side with a failed secondary - not sure whether that's the case with a failed primary.

Just because you have bought new coil packs doesn't guarantee they're good. Swap the LH primary over to the RH side and see if the RH then fires and LH doesn't. Then change the RH primary plug and see if that helps.

Are you sure it's ignition-related? Do the plugs on the RH cylinder get wet with unburned fuel? If not, it could be a fuel problem not an ignition one. Check wiring to the injector, try swapping injectors side to side etc.

Edit; Sorry - just re-read your last post and you are getting fuel through. My money would be on the RH primary coil or plug.

Thanks - I will try swapping them over now and see if that helps. Seems odd that the RH pot wasn't firing on either primary or secondary - whereas both are heating up the header on the LHS. Off to try it now :)
 
So definitely not a 'sparks' issue then! Have swapped over the primary and associated spark plug and still nothing from the RH pot. I have also held the plug against the block and have a nice fat spark! What sort of job is it swapping injectors...supposed to be setting off with friends tomorrow morning at Sparrow Fart. Looking more like an abortive holiday job :-(
 
Next step...popped the RH injector out. I has a strong spray pattern and fuel is definitely there in abundance. However, the o ring had perished and there were black bits of rubber inside the injector body. I am carefully cleaning them out now - and will replace the o-rings to see if that has any effect perhaps?

Got compression, fuel and sharks - can't see why she won't fire up :-(
 
I had similar symptoms on an 1150 GS-- replaced a coil but it took a few minutes of running on one cylinder before the 2nd one sprang into life. Not sure why-- fouled plugs maybe?

The compression reading on mine was on the borderline between 'Ok' and 'too low'. It ran okay once it has decided to run on both cylinders, despite the low compression so unless your motor is totally shot it's unlikely to be the compression.

Good luck, hope you get it sorted.
 
Check your valve clearances. Maybe look down the throttle body and check the butterfly moves when the throttle grip is turned.
 
Thanks everyone. Having cleaned the injector through and replaced the o-rings, I then had her running 75% better - now the RH cylinder is firing and getting hot. Still running off-beat though so not right. To cap it all, bow have a terrible sound from the clutch basket/gearbox when I let the clutch out.

Unsure id this is a direct result of the engine running out of balance still...would it do that?

Sounds like a death-rattle, don't think I dare take it to Scotland tomorrow
 
Thanks everyone. Having cleaned the injector through and replaced the o-rings, I then had her running 75% better - now the RH cylinder is firing and getting hot. Still running off-beat though so not right. To cap it all, bow have a terrible sound from the clutch basket/gearbox when I let the clutch out.

Unsure id this is a direct result of the engine running out of balance still...would it do that?

Sounds like a death-rattle, don't think I dare take it to Scotland tomorrow

Sounds like you've got it in gear on the centre stand of so then don't.
All the u/js are revolving at acute angles, not good for them at all.
 
Got some spare coils in Wetherby which I bought as s/h spares a while back, think there are 2 poss three sets of primary/secondaries.
Call in on way passed if you have problems (assuming you've left on the GS)
 
Pity these panicky thread things just frazzle out despite our input.

OP will be back in a fortnight saying what a lovely time he had and his steed was awesome….just forgot to put fuel in it.:D
 
Have you swapped the spark plugs left/right?

If you disconnect an idle stepper motor the cylinder wont get fuel until its turning at about 1500 rpm. Swap the steppers left/right and see if the symptom moves. (I believe they are not handed).

In neutral, the clutch and/or gearbox input shaft will rattle/chatter on a 50K miles bike. It sounds horrendous but mine's rattled for at least 20K miles with no ill effects i can detect.

As @flatdof says running it in gear on the stand is not a good idea. The unloaded gears will chatter horribly and UJs will be hammered as well.
 
I had a similar fault and found a faulty O2 sensor in the exhaust. Pull the O2 sensor, if it is super sooty then it may have died, light grey is good.

If it is very sooty then it is likely that it is sending the wrong voltage signal back to the computer. The computer then reeds this as a lean mixture soo it over fuels the bike...... and you get a cold cylinder and misfiring.

I'd leave for your trip but stop at Halfords.......You can by BMW O2 sensors for a million quid, or just go to the car parts man and ask for a 4 wire O2 sensor (take yours as a thread and tip length comparison) buy a packet of wire joiners as you will need to join the BMW plug to the sensor and you are good. You will need some players to connect the wires. When you get home you can do a real nice soldered joint with some heat shrink over the joints.

I've done this on a trip and it worked out great. I don't think the sensor wires have any polarity.

Have a good holiday.
 
My O2 sensors went sooty - both of them. The cause was faulty primary coils causing missfire.

I replaced two perfectly good sensors because I have never before had two coils go down with the same fault within a few miles of each other.

Missfiring coils do not ignite all of the fuel so the O2 sensors see excess oxygen. The ECU adds more fuel causing rich running and sooty O2 sensors.

You can join twisted strand copper wires with heat shrink sleeve. Fit sleeve to one side, twist wires together, slip sleeve over and shrink it with a cigarette lighter. The resultant joint is officially a temporary fix but in some ways is better than solder.
 
Thanks for the input

Thanks for all of the helpful input guys...the only reason I had not re-posted before is that I failed to get the bike fixed in time for the holiday and had to borrow a friends Pan-European.

Having got back I am only now setting about cracking on with the issues again. So far, I have had the injectors out and ultrasonically cleaned and tested for both resistance and flow. Both are now 100%!

Fitted to the bike this morning and still no go :roll eyes:

Next step is to have the valve covers off...just about to set about that now so will keep you informed.
 
No I haven't done that...will need to look that one up. I seem to recall its disconnect the battery and then rotate the throttle a number of times? Am I in the right track?
 
Pity these panicky thread things just frazzle out despite our input.

OP will be back in a fortnight saying what a lovely time he had and his steed was awesome….just forgot to put fuel in it.:D

Might have seemed that way, but not the case I assure you. Could not resolve the problem in time for the bike holiday sadly, so borrowed a mates Pan for the trip. Now I am back I am trying to fix the issue again. Just had injectors cleaned and tested - no good. Onwards we go :)
 
2 things

Before pulling valve covers off Do a compression test!

If you have a significant variance from the other cylinder then move a step forward to check rocker clearances etc etc

Have you changed the spark plugs they are incredibly intolerant to frequent cold starts with no run to full working heat
 


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