Boxerworks.com

Hello All,

New member here. Obliged to be in your company. I need help!

I just bought a 73 LWB R60/5 and I'm having issues. When I bought the bike (in February) it had a new battery. I could not get it to start with either the electric starter or with kicks. I brought her home and cleaned out the carbs/petcocks, put on new plugs and wires, did an oil change and all seemed well. I took a 30 minute ride and she ran great after starting fairly easily.

The next day...I rode to work (30 miles), and got there fine. On the way home however, once she warmed up she started misfiring, losing power, and running roughly. I got her home and self-diagnosed a point/condenser issue. I replaced both, set the right gap, and got her to start again. She ran well. I shut her down, went to get a helmet on to go for a ride and could not get her to start again. I tested the plugs, and no spark.

Now I figure that the coils are bad. I bought 2 new (aftermarket duralast) coils and put them on last night. Nothing. I couldn't get a darn thing. Tested the plugs again on new coils and nothing. The white light on my instrument panel below the oil light is on steadily. Does this indicate my problem at all? I am at a stand still and don't know what to do next. Are the aftermarket coils the problem? I'm going nuts here!

This sounds like a wiring problem, most likely between the 12 vdc power coming in to the first coil, and the points. There are 6 spade connectors in this path, and the problem is likely in or around one of those connections. A crushed wire is also a good possibility.

My suggestion - remove the front cover and both spark plugs. Turn the key on and rotate the engine with the kick start or Allen key in the alternator. You should see and hear a spark when the points open. If you don't, get a multi meter or a continuity tester and determine at what point along the path the power is lost. If you do, the problem may be intermittent. Wiggle the spade conntector, stretch the wire at each connection to see if you can re-create the problem.

Good luck, and don't keep us in suspense......

All work should start with a valve adjustment first. Curious...how did you test the plugs? You said you set the "right gap". What about the timing?

White light? What system is that referring to? If it's the charge light, and the bulb has faded from red to white, being on all the time prior to getting the bike started is a good thing.

I'm not totally familiar with Enduralast coils. You should have two coils with rated primary resistance of 1.5 ohms...total in series resistance of 3 ohms. Something like the Bosch coils on Motorrad Elektrik's site:

http://www.motoelekt.com/ignition.htm

Kurt in S.A.

I do have intentions to do a valve adjustment however I think according to the manual, the bike needs to be warm first...I can't get the bike to even start now though. As far as the gap comment goes, I was referring to the gap I set on the new points. I did'nt mess with the gap on the sparkplugs. I already returned those crap coild and will be ordering the bosch coils to replace what I have.

Toaster1988,
Have you checked to see if the front cover you removed to access the points and condenser is grounding the points lead? This is a common situation where you replace the points and condenser and then when tightening down the front cover, the points lead gets crushed against the case with the front cover. Asked another way: Have you tried starting the bike with the front cover off? Of course, disconnect the battery prior to removing or reassembling the front cover to avoid shorting the diode board or horns.

BTW, Most instructions I've read show the bike should be cold when you set the valve lash.

DaveM
1975 R90S
2000 R1100RT

toaster1988 wrote:I do have intentions to do a valve adjustment however I think according to the manual, the bike needs to be warm first...I can't get the bike to even start now though. As far as the gap comment goes, I was referring to the gap I set on the new points.

Valve adjustments should be done stone cold. I figured you were talking about points gap...but that's only part of the story when it comes to ignition timing. In fact, the gap can be set over quite a range and still work fine. A lot of people are hung up on setting the gap to say 0.016" and not changing it...it's certainly a good place to start. But if you can't rotate the backing plate enough to bring the timing into line, then change your points gap.

Kurt in S.A.

I second DaveM. The clearances are spec'd to allow for thermal expansion. Enough clearnce that when things warm up and expand the valve still closes fully, but tight enough to not give excessive "banging", for lack of a better term, when cold. The exhaust valve has a wider clearance because it gets hotter than the intake valve, and thus expands more.

Snowbum's website has lots o' information on it.

http://bmwmotorcycletech.info/setvalves.htm

I'm sure it's in there somewhere...

Has anyone ever checked valve clearances hot? Seems like old GSPD had some thoughts on that. I wonder if it's really much different than cold. I'm thinking that while the thermal expansion rates are certainly different, the final values of expansion are probably close to the same. From a very unscientific standpoint, the noise of my valves just after engine start and from when I get back from a ride are essentially the same.

Kurt in S.A.

Kurt in S.A. wrote:From a very unscientific standpoint, the noise of my valves just after engine start and from when I get back from a ride are essentially the same.

Kurt in S.A.

Which actually implies that the clearances are a little tighter when hot, since the thinner oil of a hot engine would tend to make your valves a little louder.

Dave Backmarker wrote:Toaster1988,
Have you checked to see if the front cover you removed to access the points and condenser is grounding the points lead? This is a common situation where you replace the points and condenser and then when tightening down the front cover, the points lead gets crushed against the case with the front cover. Asked another way: Have you tried starting the bike with the front cover off? Of course, disconnect the battery prior to removing or reassembling the front cover to avoid shorting the diode board or horns.

BTW, Most instructions I've read show the bike should be cold when you set the valve lash.

DaveM
1975 R90S
2000 R1100RT

Thanks Dave! When I put my front engine cover back on I was careful NOT to crush the points lead, however I had to jimmy it in place a little bit and apparently the lead moved because sure enough I was crushing it. With the engine cover off she fired first try and ran strong on the 30 minute ride to work today! What a spectacular feeling to have this problem solved! Thanks for the advice and making me double check and find a mistake I made.