Hubster, I need your expert assistance...

I just limped home from a ride on my BMW S1000RR, lost power about 16 miles from the house, exhaust sound went flat, no throttle response, losing power and engine dying at idle with raw fuel smell from the exhaust.

My TFT Display shows no Diagnostic Warnings but I have the Bren Tune Stage 1 that may be preventing codes, don't know yet.

Bike ran terrible, not super rough but just no beans, no throttle response and trying to quit everytime I pulled in the clutch, could barely manage 58 mph in 3rd gear.

Here's a Youtube video I just shot out in the garage, engine started and ran at idle but sounds rough, revved it up a bit and back to idle and it quits every time.

https://youtu.be/pX_4rIJFUeM]Your text to link here...

Ignore Yellow Warning in the Display on startup, it's just for the oil service, I change the oil myself and BMW wants $75 to clear the warning....

* Last updated by: Kruz on 8/10/2025 @ 4:30 PM *

My best guess at this point is a coil stick went bad, a known issue with '20 and on S1000RR and M1000RR.

Doesn't the BrenTune tool read codes? Video sounds pretty nasty. Maybe even a little metallic. I would pull the drain plug for just a cup or two of oil and look for debris. if it's still good then reuse the drained oil. If you smell fuel then your ignition isn't working or your fueling is too extreme. Maybe it's time to pull your spark plugs.

I don't believe that bike has 5000 miles on it so the spark plugs would be low on the list of primary suspects. The plugs are definitely on the list though. The coil are easy to check though. Check that they're fully seated and the connectors are latched. If you have a faulty one, that will entail a more thorough investigation and some kind of electrical test tool such as a multimeter.

I hear what sounds like a mild slap in the engine but it's so hard to discern funny noises from normal in these videos x10 if you don't own the bike. If that were a Ducati or the Yamaha crossplane engine, I'd say it sounded normal but the BMW is an inline four like most crotch rockets. From the sound, it's real obvious you're running on less than four cylinders. On my busa, I had a bent pin in a coil connector after installing the fuel management module. The bike ran on three cylinders. I didn't notice anything unusual about the sound and it ran as normal in a test ride around the block. It was giving a code though. The slightly smaller engine might react to running on three cylinders more noticeably. ...or maybe you have two cylinders out. Three cylinders on my busa and it seemed to run as normal at small throttle and no smell of gas. From the provided info, it doesn't sound like you could have a bent pin but I'll just mention, that bent pin on my busa was more or less visually unnoticeable unless scrutinized extremely close. It was hardly bent at all.

Most likely, this is a simple electrical problem and you will just need to track it down. Probably a faulty stick coil. If that's it, replace all of them. I'd almost bet there is an aftermarket alternative.

I'll wait for Hub's response but I'd say the first step is to keep the bike idling and pull each coil connector one at a time to find which cylinder(s) isn't firing. Next step is find out which diagnostic tool you need to check stick coil voltage and buy it. Hopefully the coil is what's causing the problem. The bike is so new, I'll be surprised if it's a unique problem.

That's a really cool bike Kruz. That's my favorite out of the whole fleet. Remember, I was ready to buy one myself before I had that crash.

* Last updated by: Rook on 8/11/2025 @ 3:15 AM *

When chasing a possible misfire I use a thermal temperature gun and just shoot the head pipes 3-4" from the head. Once the cold cylinder is found I swap that coil to an adjacent cylinder and repeat the test. If it follow's the coil you've got your answer. If it remains in the first cylinder location then you're looking at fuel injector, electrical component, wiring, vacuum or engine mechanical concerns. I don't recommend disconnecting coils while running as that could spike the ECU, Certain Ford vehicles had that warning in their diagnostic procedures.

Thanks for all the inputs folks, at this point I'm pretty sure it's just a dead stick coil, BMW has had an ongoing issue with these failing early, watch BT Moto video below, they're about $200 apiece....yikes! I wanted to get Hub's take as I rode the bike home yesterday with what felt like a dead cylinder and was wondering if I washed my rings with fuel on that cylinder since it wasn't firing the plug but still injecting fuel based on the raw gas smell from the exhaust.

https://www.youtube.com/watch?v=muoaUMcWvCE

* Last updated by: Kruz on 8/11/2025 @ 7:55 AM *

Yep, here's a 2020 S1000RR virtually identical to mine, sounds like the same problem.It's too bad BMW is not stepping up to the plate and replacing these bad coils under a general recall.

https://www.youtube.com/watch?v=C4Hq641da6s

Literally dozens of threads on the 2020 BMW S1000RR coil issues, the bad part is apparently a defective coil can also take out the ECU coil drivers and poof, new ECU on top of more coils. This bike has already cost me more in unscheduled maintenance than all of my bikes combined over the past 20 years. The carbon fiber rim crack alone set me back $3700. No more BMWs for me, nice bike but not worth the expense!

* Last updated by: Kruz on 8/11/2025 @ 2:45 PM *

Cold cylinder test, #1 and #3 are both dead so two cylinders affected. I'm hearing one bad coil can take out the others, what a crap design from BMW.

I had a sneaking suspicion it might be more than one cylinder not firing. As I mentioned, I didn't even notice my busa idling or running any different on three cylinders.

Yes at least two cylinders are completely dead, which brings up the question in my mind, since I do this kind of stuff on aircraft for a living, I'm not buying two coils failed at the exact same time by random chance unless one coil failure can effect other adjacent coils somehow. It would have to be back through the ECU, maybe smoking the coil drivers in the ECU in which case I may be looking at an ECU also. What a complete shit design if a single coil failure can run up $2000-$3000 in total damages. I have owned 26 motorcycles in my life and had one previous coil failure back in 1972 on a Norton with ancient Lucas electronics and that was a simple fix, slap on a $12 coil and you're back in business.

Where is the Hubinator when we need him, he's gone MIA....

* Last updated by: Kruz on 8/12/2025 @ 10:56 AM *

This is starting to turn into a nightmare, this BMW is a money pit, cracked carbon front wheel cost me $4000 a yaer ago and now this. I called BMW and they recommend four new updated coils at $1000 plus the labor to install as the old coils all fail eventually. They also said they have to update the ECU for the new coils so my Bren Tune Stage 1 flash is no good now and I'll have to pay for that again, plus they said they've seen cases of a bad ignition coil taking out the entire ECU, don't know until they look at it God only knows what that costs. So conservatively we are looking at a possible $3000-$4000+ repair bill over a shitty ignition coil. Screw BMW, I will never buy anything from them ever again.

For the quick and dirty, meaning, swap coils so 1 and 3 fire up, meaning, ECU is good and didn't backwash a spike. Then if it shows 2 and 4 not firing, then it's 2 new coils and sell it.

Say you keep it... then 4 new coils, 4 new spark plugs, call it a day.

Had my experience with a used boxer and a new boxer. After the new one, no more bmw's for me.

That's a shame because that's my favorite bike out of the bunch. The wheel crack wasn't the bike's fault. The stick coils are UPDATED. They must be better than the originals. Hopefully they were able to perfect them, a stick coil isn't that complicated. I'd spend the money. If you fix it and sell it, maybe someone else enjoys the bike trouble free for the rest of its years. There could be more bugs in the design that will cost you money down the road but don't you think you'd have heard of them by now?

I'd check with the BMW service manual if you have access to one as my Busa manual has 2 simple ignition coil tests you can do with an ohm meter. You're basically just confirming primary and secondary windings along with the lead to the plug which sometimes has a resistor between the coil and the lead. If you can't access the factory specs and test procedure testing them all in the same way maybe revealing and it could possibly be just one that has failed? Some automotive manufacturers will fire the opposing cylinders on both compression and exhaust strokes as a way to clean some emissions and can cause 2 cylinders down from 1 failed coil. I know the ignition rotor at the pickup coil on the ZX14r is stamped 1/4 and 2/3 180 degrees apart.

Ordered four new coll sticks and sparkplugs, $954, ouch! Should be here in a few days and then I'll know for sure. This has been a PITA!

Sure but worth it. Buy an expensive bike, it will be expensive to maintain, I guess. That really is a great bike though. I wouldn't sell it off. I'd put in on display in the house before I did that. I imagine any bugs that get worked out will be applicable to the earlier gens. Chances are, there won't be any more you need to deal with and if you do, that surely will put the bulletproof stamp on the bike. Japanese bikes are mass market and they're thoroughly understood. That Bimmer is in a class of its own.

I hope you swapped the good with the bad to see if it backwashed the ECU.

Not to add worry to the situation but I've heard a handful of stories about these new gen BMWs eating themselves up. Melting pistons, broken spark plugs, broken rings, mystery metal chunks in the oil, etc. They sure are pretty and sure are fast, but it seems at a cost. BMW did a good job with the engineering as far as milking every drop of power out of the engine, unfortunately that requires sophisticated and imperfect metallurgy. Bikes are created in Hungary/Austria/Croatia, assembled there (or Germany), and then shipped over here. Lots of variables to consider as far as quality control.

I'd check fuel pump and all your fuses. Fingers crossed you can return the $1,000 in ignition parts and it's something easy. You wouldn't be the first guy I know with a European bike that buys parts worth thousands every few months...

Last resort- dealer......... I hate saying that but they have software that interfaces with the bike. It'll tell them everything wrong with the bike in a crazy level of detail. I bought some dealer software to diagnose my Audi a year or so ago, it's insane how detailed those scans get. Your beemer bike isn't too different

Coils and plugs arrive on Wednesday, I had a buddy that works for a local powersports company as a mechanic come over and pull the codes with his BMW GS911 diagnostic tool, there were a couple CAN communication errors from several years ago and that was it.

We cleared those, started it up, no new codes. He confirmed cylinders 2 and 4 were dead with an infrared thermometer.

The coil/sparkplug issue is well known on this machine, early P/N coils were notorious for being ticking time bombs, most racers keep a couple spare coils around just in case.

My understanding is the primary and secondary coils are fine, it's the TTL circuit that is prone to fail.

We'll know for certain in a few more days when I get the new parts installed, I ordered third gen parts that are supposed to have the coil problem solved.

https://knowledge.ni.com/KnowledgeArticleDetails?id=kA03q000000YRMRCA4&l=en-US

* Last updated by: Kruz on 8/30/2025 @ 7:08 PM *

Well Hub, new ignition coils and plugs finally arrived and I got around to changing them this morning. Here's what I found when I removed the tank and airbox, top photo. The top of #4 coil was completely separated from the bottom half. Installed new plugs and coils and fired it up and.....nope, still dead on # 2 and # 4 cylinders, not #1 and #3 as I reported earlier, that was a typo. It appears there was a lot of arcing going on for some length of time at #4. Plugged in GS911, no codes, everything looks fine. So, I'm now out $1100 for plugs and coils and 3 hours of time and bike is still dead on #2 and #4. What next, new ECM? My thoughts now are all the arcing at the #4 secondary fed back into the ECM and smoked coil drivers for both #2 and #4 although I don't know if those two are connected at the coil drivers.

* Last updated by: Kruz on 9/8/2025 @ 9:56 PM *

Here is what I found when the fuel tank and airbox came off.

* Last updated by: Kruz on 9/9/2025 @ 4:31 AM *

That is sad. My only guess was a twist and not a pull first caused that? Has to be a brutal pull up. I can't see something like that just loosen itself and lay dead in its side. That means no follow thru to ground but a backwash from DC to AC back into the ECM.

Looks like an ECM to fix it. Wonder why no code for each cylinder. On the ZX it cover codes for spark.

2nd owner BS is more call BM and see if they'd do a good-service by offering a new ECM. Might get them on a 50,000 mile epa status on emissions. I recall that is the mileage window to no charge to the customer on a fuel related issue, meaning, emissions related.

Good luck with the call

I'm a bit rusty on my Hubbish but it sounds like you are saying previous owner or mechanic strong armed the coil during prior maintenance and cracked it leading to complete coil failure and separation? High voltage fed back into the primary circuit and destroyed coil driver transistors. Makes sense for #4 but why #2 also and was this what caused my TFT to change modes from Race Pro Customs Settings back to standard Race Mode? That one had me puzzled, first thing I noticed when it shutdown and yes, there are no stored internal fault codes of any type and no warnings on the TFT display.

Your hubbish is spot on, Kruz. I'm always puzzled with electronics so I have no answers for you on that, Kruz.

What about that call to get a good will brain box?

* Last updated by: Hub on 9/13/2025 @ 2:09 AM *