R65 no spark

[crandall]

Hi,

My 1981 r65 was running great until I washed it, now it's not producing a spark. I've removed the tank and sprayed wd40 over everything and dried it all off. But when I switch the ignition off it produces one spark. The battery is fully charged. It was cutting out a few days before when I switched the lights on, but this was sorted by a squirt of oil in the ignition switch. Looking forward to your suggestions as I'm a bit stuck.

Clint

[DerekM]

What do you mean it produced one spark? it sounds like you knocked a wire loose or got water in a bad spot and you lost connectivity. I would check for spark with a plug against the cylinder and then see if its just one side not sparking or both.

[crandall]

It's like switching the ignition off is creating an impulse like when points open and sparks once. I have laid a plug on the cylinder on both sides and it's the same story. No spark when cranking the engine over and then a spark as I switch off. All the connections under the tank are dry now.

[Luca]

I don't know where it's wired in so I can't say for sure, but it sounds like the culprit is the killswitch on your throttle side controls.  Try drying it out/a little wd40 and move it through the positions a few times.

That is if you didn't just forget to turn the switch to the on position... I remember my heart sank when my revived beemer wouldn't even give a puff when I first tried firing it up... somebody had left the killswitch off    

[crandall]

Thanks Luca, I'll try cleaning up the kill switch, but it was the ignition key switch that caused it to cut out when I switched it to the headlamp position. Is there a way I can bypass the switch to eliminate it from my enquiries?

[montmil]

There's one very important item that, if water intrudes, will prevent sparks at the plugs...

Come on, guys. say it with me... The OEM Bosch Crack-O-Matic ignition coil.

if you still have the black and gray Bosch twin lead ignition coil, I would remove it and inspect it closely for tiny cracks. Any amount of moisture, even a really foggy day, can stop the engine dead in the water. Clean off the coil and check it thoroughly. Usually, but not always, circular cracks can be seen on the end.



If/when you find cracks, replace the unit with a Dyna "Brown" ignition coil from Rick Jones at Motorrad Elektrik. http://www.motoelekt.com/ignition.htm

[Bob_Roller]

I'm with Monte on this, it's quite common for the gray and black OEM coil to give you problems when it gets damp or wet .

If you have one of these, same yourself trouble down the road, it will leave you stranded at some point, it's what they do .

Turning the ignition switch on and off and looking for a single spark, is the test to see if the components in the ignition system are working .

What color is the spark a bright blue / white, or a reddish orange color ??

[Luca]

I've never tried it, but you'd have to somehow bypass the switch.  Or you could test the switch for continuity with a multimeter.

Monte and Bob are both right that the Bosch coil is not so hot--it cracks and stops working with moisture-- and that replacing with a Dyna brown is the way to go.  Unless the spark you are getting on shutdown is weak, though, I wouldn't rule out a triggering problem.

[Tony Smith]

I agree with the comments made about the BMW OEM coil.

Although if you do decide to replace it, a late model Mercury outboard coil is worth considering as it is cheaper, guaranteed waterproof, is shielded against RF emission (which is an issue if you use electronics whilst riding your R65) and can be easily mounted in the R65 on a piece of 3*1" box section steel - which also provides a good heat sink. If interested I will post photos of the one mounted to my R65.

BUT, in this instance I think that you have either a fault in your ignition switch (my wife insists on having about 1lb of doo-hickys, gee-gaws and other cr@p hanging on her key ring and has bought two new ignition switches in the 35 years she has owned her R65/80 and your symptoms accurate replicate what has happened to her. By the way squiritng oil of WD40 into an electrical switch is not such a good idea as when it combines with the crud already down there it can form a conductive paste, dielectric grease if you must.

The switch can be tested with a multimeter and reference to the wiring diagram which will quickly tell you if it is not maintaining contact/current flow when it should.
 
The second thing to look at is your main power feed going back to the coil and electronics from the ignition switch. I have had that partially fail through fatigue near the steering head and to then leave a perplexing intermittent fault in that the bike would start and run normally but stop randomly when the wire strands inside the unbroken plastic sheath pulled apart. Ten minutes later the cursed thing would start and would seem fine - for a while.

If your switch checks out, and you cannot see any damage to the harness, there is a spare positive 12V switched output on the standard ignition switch, run a reasonably heavy "doubler cable" back to the electronics and see if that cures your problem. If it does, cut and terminate the old feed as it present a small fire risk.

[D Mann]

I have been reading a lot off articles on Snowbums site and there is something about this in his ignition article http://bmwmotorcycletech.info/Ignition.htm  . Down quite a way there is a gray section where he he tests the module and the coils this way. Just looking real quick it looks like your coils and ignition module are good. You may need to check your Hall element in the canister. Hope you get her going.

[montmil]

A side note: The Euro R65 that is the topic of concern has a different ignition switch than those R65s sold here in the Colonies. The USofA Gubmint requires vehicles to have "headlights on" so our ignition switches do not have the Headlight On position. We don't have that choice.

When first purchased and unknown by self, my '81 R65 had an ignition switch pirated from a riding lawnmower. Rather embarassing to be told by the parts guy at Lone Star BMW-Triumph is Austin that they couldn't supply me with a key blank.

After dumping the old steam gauges and going all digital, I installed a semi-hidden HD marine-grade toggle switch for the ignition.

[crandall]

Hi all,

Thank you so much for all these very helpful comments, it's very much appreciated. The coils are new, not the originals but generic universal coils they have been running great for the last six months. I replaced the original as it was cracked just as you guys mentioned.

I like the switch theory and when I get home tomorrow I'm going to try and bypass the switch. I'll let you know what happens.

[Luca]

Sorry to lead you astray, Clint, but it isn't the killswitch. The coil gets no power with the killswitch off so you would not get any spark when turning the ignition off if the killswitch was bad.

I kinda stumbled right over it but D Mann nailed it.  The "bean can" Hall effect sensor is the first thing you should check.  It sounds like the coil is getting juice and the icu is discharging the coil on shutdown as it should, but the coil isn't getting the signal to fire during engine rotation from the bean can.   Make sure to disconnect the battery before removing or installing the front cover.

Did you use the hose on the engine?  You might have sprayed water through the cooling slots on the sides of the front cover.

[Matt Chapter]

The USofA Gubmint requires vehicles to have "headlights on" so our ignition switches do not have the Headlight On position. We don't have that choice.

Not "from the showroom floor" per se, but they don't inspect the packages coming from across the sea, let's say.

For a modest upcharge, when you replace your left hand control, motobins (or any other old world supplier) will supply you with the headlight on off switch.  A subtle, nifty piece of bling for a USA spec R65.

[montmil]

Perhaps the external wire connector on the bean can but it would be mighty hard to get water into the can itself. Plus, the Honeywell-produced Hall sensor -I've replaced two in cans I've built up for spares- is all but water tight. Now that diode board is open exposure but also solid state and may not be part of the "no spark" issue.

None of my five bikes have ever seen a car wash or a garden hose. Yes, it takes more time to drag out a bucket, sponges, rags, bristle brush, etc to clean up a dirty bike but it will start when cleaned the old-fashioned, laborious way.