Stick coil question / reassurance!

[Jhock]

First off I know there are a lot of threads on this subject but I want check I have done the right thing before I order the stick coils.

The bike is a r1150gs 2003 twin spark model.

The issue is at about 4000 it gets very lumpy and does not like to rev further, it will but it is not happy.

So here is what I have done so far:

Had both Coil packs out and checked for spark, nothing from either one, one looks fecked but I know that does not always mean they have gone. This was done by putting a new spark plug in the coil and running the bike and checking for spark, of which there was none!

Bike still runs with both off, so it looks like the secondary sparks are OK, incidentally where are they! I want to change them as part of the service I am giving it.

I have swapped the coils to both sides and checked for spark still nothing.

So as far as I can tell it both coil packs are shot, so a simple fix, but I am sure I could be wrong and something else might be the issue?

If any one can add to my list of what I should check that would be good.

Thanks.

 

[Jhock]

Forgot to mention the bike is new to me, so this is not sudden development, it's been running badly since I had it.

 

[mspenz]

Try unplugging the secondary plugs and see if the bike starts/runs on the primary set up, if it doesn't start/run then the primary coils are likely to be the problem. The secondary plugs are under the cylinders and may be covered with a plastic shroud so might not be too obvious.

It's amazing just how well the twin spark will run on secondary plugs alone but it certainly won't feel right

 

[Ian J Hartley]

I'm curious to know if you have had the servo brake system removed.

Usually when people remove the servo they remove the two small relays to the bottom left of this picture. They do this because they have no real idea what the relays do, and therefore assume that they are both part of the ABS system. This is not the case. The blue relay is the ABS warning relay. The yellow relay is the load relief relay for the stick coils. It allows a second electrical path to the coils to allow for increased current flow.

 

[Jhock]

The bike still has the servo brakes in place and working so I assume the relays are in place, In will check tomorrow to be sure. Thanks.

 

[Jhock]

Another thought on the subject, is there a way I can check if power is getting the coil packs? Can put a volt meter across the plugs that go into them to be sure they are getting power?

I have ordered new ones, they are always a good thing to have spare, but I suspect the old one are gone.

 

[ahutcheon]

IIRC there are only two terminals in the stick coil connector. In which case you'll only see 12v as the coil is charged/fired, which might be too narrow a pulse to show up on a meter. I haven't tried it. I guess if you've got an oscilloscope it would be easy enough to see the pulse...

 

[Bendy toy]

Are these stick coils similar to those used in the 1200?
Mine had both primaries fail virtually at the same time. They made diagnosis a nightmare because swapping them left/right made no difference. The new coils have a stainless case. The old ones were black painted and had a sort of hot electrical smell. I put that down to them running inside a hot cylinder head but clearly it was not normal to have hot smelling coils.

http://easyautodiagnostics.com/misc-index/two-wire-cop-coil-tests-1

 

[stolzy]

Personally I would bite the bullet and replace the stick coils. Does the bike start and run if you remove the secondary plug caps?

If one looks shot, it almost certainly is shot. the other may or may not be, but will likely go the same way sometime soon.

The bike will be transformed with new sticks.

 

[Slipperyeel]

I agree with Stolzy. Just replace them. I am about to do precisely the same thing (just one side was replaced last year - i should have done both!). Admittedly they're not cheap, but there are no (straightforward) alternatives...

 

[Jhock]

I have indeed bit the bullet and ordered 2, my only concern is there is something else going on causing a lack of power to the primary coils, but I am 95% the new coils will sort it out.

 

[David Morton]

have you checked the lamba censer on the exhaust

had a similar issue and it was the lamba censer

cheers davey

 

[Slipperyeel]

You've got an important thing off the list by buying new ones (are the old items painted black?). They take just a few minutes to replace so you should get a result quite quickly.

 

[Roger 04 RT]

I'm curious to know if you have had the servo brake system removed.

Usually when people remove the servo they remove the two small relays to the bottom left of this picture. They do this because they have no real idea what the relays do, and therefore assume that they are both part of the ABS system. This is not the case. The blue relay is the ABS warning relay. The yellow relay is the load relief relay for the stick coils. It allows a second electrical path to the coils to allow for increased current flow.

On my US R1150RT Twin Spark, the relay in the lower left that you mention is for Fog lights. When a 2nd Load Relay is added, it is located to the right of the (open in the photo) white Coding Plug socket.

The 2nd Load Relay was a change that BMW made somewhere along the line. In the early models, the stick coils were powered directly from the Key switch. In later models, the key switch controlled a relay which connects the coils directly to the battery through the 2nd Load Relay.

I think the 2nd Load Relay was a quiet important change that BMW made but never explained why--probably so they didn't have to retrofit all earlier bikes.

Here is the project I just finished to add the relay: http://ukgser.com/forums/showthread.php/401537-R1150R-GS-RT-2nd-Load-Relay-for-Twin-Spark.

 

[mspenz]

Try unplugging the secondary plugs and see if the bike starts/runs on the primary set up, if it doesn't start/run then the primary coils are likely to be the problem. The secondary plugs are under the cylinders and may be covered with a plastic shroud so might not be too obvious.

It's amazing just how well the twin spark will run on secondary plugs alone but it certainly won't feel right

Again, have you tried to start it after unplugging the lower secondary plugs? Ask me why I know.....

 

[Jhock]

Again, have you tried to start it after unplugging the lower secondary plugs? Ask me why I know.....

I have indeed, and it won't start.

 

[Captain Black]

I have indeed, and it won't start.

That's your answer then I'd say.

New stick coil thingies.

 

[mspenz]

I have indeed, and it won't start.

Bummer! Rest assured though that the new coils 'should' last for several thousand miles of trouble free riding (I'd still grab a replacement £30 2nd hand unit from the likes of Motorworks if you intend to do any long Euro trips ).

 

[mspenz]

You've got an important thing off the list by buying new ones (are the old items painted black?). They take just a few minutes to replace so you should get a result quite quickly.

They also have a date stamped on them so you can get an idea of how much use they may have had...although that apparently means nothing!

 

[Jhock]

New coils have been fitted, what a difference! How I remember the 1150gs. Thanks for all the advice. Next job is to get a vacuum gauge and get the throttles balanced. The tick over is a bit high also now, about 1200rpm when hot, I am guessing it was turned up to make it run OK with the failed coils. I did see on Youtube vid that the tick over screws should be 1.5 turns from full. So screw them in all the way and then 1.5 turns out, not sure how true that is.