2004 Hard starting dual spark R1150R

[pomurchu1]

My 2004 R1150R (50,170 miles) suddenly developed a cold hard starting starting issue. It takes a lot of cranking and various faffing around to eventually get it to fire up. Once it is warmed up though it starts like it used to - almost immediately on pressing the start button.
- There are no other issues with the bike and it doesnt seem like ive lost any power. I'm not a real aggressive rider though so not sure if I would notice a subtle drop in power.
- This issue came on suddenly - a day after I changed the oil and washed it last weekend. However I rode it immediately after the oil change and it fired up fine.

I have done the following:
1. Checked the Battery. Battery is ~2months old. When fully charged (engine off) it reads 13.3VDC measured at the battery terminals. When I turn on the ignition it reads
12.2VDC. When I start cranking it goes to 10.3VDC. I think this is normal right?
2. I checked for spark on the upper plugs (i have a dual spark engine). There is no spark on the right cylinder and a faint spark on the left cylinder. I swapped the coils between left and right and the faint spark/ No spark followed the coils.

I suspect the stick coils after test #2. Before I pull the trigger on new coils I would like to make sure. My buddy has an '03 1150GS (single spark). Does anyone know if single spark stick coils would work on my dual spark bike to do a quick test?

BTW the Part number for the coil on my bike is 7 671 896-01

Thanks
Paul

 

[senseamidmadness]

I'm not a dual-spark owner but from what I know of automotive diagnostics, you've definitely found a problem from that coil swap test. It doesn't necessarily mean the one coil is bad, though it's likely as they're a common failure point -- you should double-check to make sure all of the electrical connections to and from the main coil and plug wires and stick coils are good. I would also test the main coil with a multimeter.

That battery voltage seems low when cranking for an almost-new battery. Batteries are most likely to show issues either very soon after purchase or much later at the end of their life cycle. Could also be a failing starter or a slightly loose electrical connection to the starter that closes up as the engine warms. Double-check your main battery cables at the ends you can access: the ones on the battery and the positive end on the starter assembly. You may have excessive resistance somewhere.

You can also, with a multimeter, test for resistance between a known ground and the negative battery cable. If you're unlucky and the resistance seems high, you might have to dig and find the other end of the negative battery cable. It lives under the battery box and is bolted to the engine.

 

[pglaves]

Whenever I hear weak spark and washed the bike in the same paragraph I wonder where water got that it shouldn't be.

My suggestion would be to take apart, clean, and dry all of the electrical connections which would affect the coil(s) in question.

 

[senseamidmadness]

Whenever I hear weak spark and washed the bike in the same paragraph I wonder where water got that it shouldn't be.

My suggestion would be to take apart, clean, and dry all of the electrical connections which would affect the coil(s) in question.

Big agreement here. Any kind of electrical issue that shows up after a bike wash immediately makes me suspect water intrusion.

I will add: after taking apart and cleaning and drying all your electrical connections, you could add some dielectric grease to them. While it's not necessary I personally do this to all my bikes when I do electrical disconnecting because I ride in the rain and it's cheap insurance. Plain silicone grease is usually sold as "dielectric grease" at the local auto parts store but I buy it cheaper online in jars from scuba suppliers.

 

[pomurchu1]

Thanks for the suggestions all. I went for a good long ride after washing the bike without issue but I’m not ruling it out as a contribution. I checked ground resistance and it was ~0.2-3 ohm everywhere. Starter + connection was a bit cruddy looking so I cleaned that up. Still the same.
There is 13.2/3 volts DC on the input to the coils during cranking - that seems to be ok from what I saw on another forum.
For future reference the single spark stick coil won’t fit on the dual spark. At least not easily.

Regarding the cranking voltage being just over 10v while cranking - I tried fully charging the battery and also connecting one of those potable jump start blocks. It didn’t change anything. In fact the cranking voltage stayed the same.

I know it’s not the best test but the starter sounds ok to my ears and is turning the engine at a good speed.

I’ll continue to check connections but I’ll also check on the alternator/ regulator/ belt portion today.

Thanks again for the suggestions

 

[RPGR90s]

Stick coils are an issue on early dual spark models. If the problem moved with the stick coil, I would be buying a new set. Also check the connector. People tend to pull the stick coils without first disconnecting them, and this can damage the fragile connectors. Ask me how I know.....

 

[BC1100S]

Whenever I hear weak spark and washed the bike in the same paragraph I wonder where water got that it shouldn't be.

My suggestion would be to take apart, clean, and dry all of the electrical connections which would affect the coil(s) in question.

As well, I found my stick coils lasted around 90,000km. Then they both went bad within a couple of thousand kilometers.

 

[pomurchu1]

Starter Disintregated

Anyone know what would cause this? I wasn’t sure but I thought the starter started to sound rough but it still turned ok to my ears. Today it made a bang and the pic shows what I found. Any idea what could have caused this?

BTW the original problem is still not solved. I swapped in a known good set of coils. Same issue. I checked for fuel - there is spray coming out of the injector which is not surprising as it runs well when started.

I tried starter fluid - it starts no problem and stays going.

Given the issue with the starter I suppose that could have been the problem. I guess I’ll soon see.

 

[senseamidmadness]

Yipes! That's a first for me.

I suppose it's possible that was a manufacturing defect, like a casting flaw in the starter housing, making it flex and slowly breaking it apart over time. That could've resulted in less starter engagement and thus less torque actually transmitted to the flywheel. Or maybe a seized or failed bearing on that end of the armature causing the motor to rip the housing to pieces? That would also have made the starter turn slower.

That or your engine is harder to turn over than it should be, which seems doubtful because it runs fine when given that starting fluid boost. It would sound weird and have trouble idling if it was resisting rotation.

We'll see when you get that new starter in!

 

[pglaves]

I have seen that happen once on an Airhead when a worn nose bushing allowed a bad mesh between the starter nose gear and the flywheel ring gear. Given the looks of this starter I would examine each and every tooth on the ring gear for damage.

 

[chrisinsc]

When I got the 2008 RT, the 1997 RT stopped being ridden as often. If I don't start it and ride it a couple times a week it becomes hard to start which I am chalking up to fuel delivery. It wasnt always like this when I didn't ride it for a few weeks but it does now. I have not dug into it yet.

 

[pglaves]

If you blow the photo up a bit and look carefully it looks like the starter nose gear teeth are a bit beat up. I really do think the ring gear is damaged.

 

[pomurchu1]

Thanks for the responses. I’m traveling for work at the moment but I’ll check the flywheel teeth when I get back.

What is meant by the “ring gear”?

 

[Omega Man]

Thanks for the responses. I’m traveling for work at the moment but I’ll check the flywheel teeth when I get back.

What is meant by the “ring gear”?

Around the outer edge of the "fly-wheel"-

Sometimes the starter can wear out a tooth....or two.

OM

 

[pomurchu1]

Around the outer edge of the "fly-wheel"-

Sometimes the starter can wear out a tooth....or two.

OM

I’ll check all the teeth and put up some pics when I get back next week. In the meantime here is the only one I have with part of the gear teeth. At least that 1/8th of the flywheel looks ok.

 

[pglaves]

I’ll check all the teeth and put up some pics when I get back next week. In the meantime here is the only one I have with part of the gear teeth. At least that 1/8th of the flywheel looks ok.
https://forums.bmwmoa.org/asset.php?fid=84098&uid=76553&d=1682383728

I suspect you are looking for one or two bad/broken teeth.

 

[pomurchu1]

Maybe I am overthinking this but I am trying to see if the two problems could have any common causes:

Problem 1: Hard starting issue when cold.
- Will start with starting fluid.
- Runs good when started.
- During troubleshooting found a weak spark on left stick coil (orange spark with no blue) and no spark on right when engine is running and starting. Swapped coils and
spark behaviour followed the coils
- I havent checked the lower spark plugs but my assumption is that these are what keeps the engine running.

Problem 2: Starter snout disintegrated.
- I did some looking online and in general (other vehicles) this can happen with the following:
a) Timing issue
b) excessive load on the flywheel/ ring gear (eg hydrolocked cylinder)
c) flywheel not centered
d) Damaged flywheel/ring gear


Would a bad HES cause poor spark and timing issues without other obvious symptoms?

 

[cajunrider]

I've replaced 2 weak starters on 1200C bikes... both were slow on motor turnover and sounded like a weak battery.
During turnover, the starter would draw lots of current, causing a weak spark and making it difficult to get it to tick over.

New starters, on both bikes, made them start like they were brand new bikes again.

Now, that said... I have no clue if this has anything to do with what you were seeing. However, weak spark leads me to believe low voltage (or bad coils).
Since it only happened when cold, maybe the starter was drawing too much current, causing low voltage, causing weak spark, causing hard start.

If ALL of that plays out accurate... Would it be possible that you had a cylinder pop at an inopportune time due to the weak spark, causing the motor kick back against the starter, which caused the starter to get spit out rather violently?

Just spit-balling here... I could very well be WAY off.

 

[riderr1150gsadv]

A starter housing falling apart like that make me wonder what its internals look like. I suspect a high current draw as well which, like CajunRider alluded too, could cause the bad starting issues.. Here is to hoping that the flywheel has no missing teeth, as that could have lead to the starter breaking as well.... YMMV

 

[pomurchu1]

I finally got a look at the flywheel. Some imperfections but I don’t see anything that justifies a new flywheel.

Here is a video. I put a bit of silver paint on the wheel at the start of the video just as a marker. Also it looks like there is a bit of a fresh scratch at one point in the rotation. I suspect that is where the starter made impact.

https://youtube.com/shorts/rwZHRNf0UcA?feature=share