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Hello and thank you

oconcon

New member
Hi everyone,

I wanted to introduce myself, as I’ve been lurking since I purchased my 1999 R1100R in January 2017 and owe many thanks for all of your insights on BMWMOA as well as those of Snowbum, the AdvRiders, Largiader, ibmwr.org, the sarcastically hilarious Valve Adjustment for Dummies and so many others. I wrote this with the hope that it may help others resolve similar issues and unlock the full potential of their R1100 oilheads. There is no way I’d have a running bike without these resources - the more I learn, the less I realize I know.

A little about me:

I’m an engineer from the North Shore of Boston who loves spending his spare time tinkering on anything with an engine. I’m very loyal to the 1999-2009 Saab 9-5 as my primary DD for my 3 hour a day commute in and out of Boston. I currently have 2001 & 2006 wagons, owned other 9-5s in the past and if I had to pick one vehicle for the rest of my life the Saab would be it. I'm a Craigslist/Bring a Trailer junkie and love to find undervalued project vehicles with good bones. Currently in the stable are a 2010 x164 MB GL550 (wife’s DD), a 2001 E38 Bimmer “Sporty Shorty” (toy car/project), a mono black Ford Excursion V10 Limited (tow vehicle/has become Dad’s DD), an 8’ Achilles RIB with a 2001 Suzuki DT5Y 2 stroke (rebuilt by me), a 1980 Pursuit 20’ cuddy with a 1991 Johnson Looper 175 and a 1988 Sonic 30SS with twin (very) customized Mercury Racing HP500 carb motors. Also an assortment of tractors/chippers/splitters/chainsaws. I have learned almost everything I know thru reading forums, growing up working on cars with my dad and my own wrenching experience over the years. All this to say that while I’m a relatively inexperienced motorcyclist, I’m a gearhead through and through.

The R1100R is my 3rd venture into the world of motorcycling - previous bikes were a 1998 Katana 750 (owned 2007-2008, rode 3800 miles) and a 2009 Moto Guzzi Griso 8V (owned 2010-2012, rode 5k miles). I sold the Katana when my wife and I were buying our first house and I sold the Moto Guzzi along with a Jeep Wrangler and a Jet Ski when selling that house to buy our second. A few years ago I started to get the “bike itch” again and as we all know, there’s only one cure. I’m now into the R1100R for ~1100 miles, so all in I have ~10k miles riding over 10 years.

The R1100R’s history:

Owner 1 - 0-11,230 miles - no records (assuming dealer serviced, perhaps I could get MAX BMW to look them up?)

Owner 2 - 11,230-58,400 miles, 2004-2012, detailed maintenance logs, mostly trouble free operation, oils/spark plugs/tires. Before sale, this owner conducted an overhaul on the bike including brake pads, all fluids, belt, HES, clutch cable, wiring covers, fuel pump, fuel filter, fuel lines, gaskets and breather-ectomy. The overhaul was prompted by random engine stops attributed to a faulty HES.

Owner 3 - 58,400-68,520 miles, detailed maintenance logs, many thousands of dollars spent on relining fuel tank, full repaint including the BMW hard panniers, HES, new fuel pump, filter + lines (again!), electrical work, drive seals, starter, Motronic computer, chasing an engine miss/hesitation and much more. The amount of work this owner and the previous owner performed in the last 10k miles was essentially a complete restoration and the bike still looks brand new, however he was never able to solve the problem of the engine intermittently missing. This owner and the previous owners were in Florida - I believe the bike was not brought to the Northeast until 2017.

Owner 4 - longtime small-displacement carbureted Honda owner in his 60’s, bought this bike in the spring of 2017 as his first foray into the world of large displacement fuel injected motorcycles. He was selling it on Craigslist after only riding it ~400 miles. His stated reason for selling was that it was too big and heavy for him.

The Purchase:

I contacted the seller, arranged a date, grabbed the Excursion from my dad, hooked up my brother’s trailer and made the trek down to Rhode Island. As soon as I arrived, the red warning flags went up - the Beemer was sitting running and warmed up in the driveway. This indicated to me that the seller at least knew “something” was not right and didn’t have confidence in a cold start. I became more skeptical reading about the engine “skipping” problem in the maintenance records provided by the seller, and the fact that it was being sold in the dead of winter. The underside of the engine was also slick with oil.

On the bright side the bike was unbelievably, nearly showroom clean other than some very slight crazing of the (2015) paint on the lower portion of the fuel tank. The chrome was perfect, the Michelin tires & brakes new. The only frame of reference i had for the engine sound was my previous big twin bike, the Griso 8V. Compared to the uncertain cammy burble and "rock tumbler" mechanical noise of the Guzzi, the Beemer oilhead sounded silky smooth to me. I went for a brief test ride and the bike ran and shifted without issue. I lowballed, the seller countered and we made a deal ($2200!).

As I began to get to know the Beemer, the “skipping” issue manifested itself. It was a frightening random occurrence, as I would twist the throttle and get a flat response. Keep twisting the throttle and the engine would “catch,” violently throwing the bike forward. I also experienced occasional surging in the 2700-3200 RPM range. The bike also occasionally idled inconsistently or stalled when coming to a stop. The hardest part was that the issues were not replicable - they just happened without warning. I turned to the forums.

1. The HES:

I read from multiple sources that the HES can cause all sorts of issues. My service records showed 2 HES replacements, but I also read that a new OEM HES isn’t necessarily a final solution since it can suffer from the same wiring issues as the original. For a baseline, I decided to send it off to Cata Dan for a rebuild. Dan was great - he informed me that although my HES tested OK on the bench, it wasn’t unheard of for issues to develop under the temperature and vibration extremes it endures at the front of the engine. Dan uses new waterproof sensors, new wiring and warranties his rebuild for life. I received the sensor back, reinstalled it on my marks and test rode the bike. It ran better overall and I thought the problem was fixed...but the same (or similar) hesitation and surging issues again occurred.

2. The Airflow:

My throttle bodies look bright and new with zero shaft play but I do not have service records of them being replaced. The “set from the factory never to be touched” stop screws were a mess - no trace of tamper paint on the left side and the right side screw & locknut were totally missing. I ordered a new screw for the right side (BMW views these throttle bodies as a unit - individual parts must be ordered from Bing USA), set it to the same depth as the left and adjusted the cable so it would “click” against the stop screw at the same time as the left on throttle release. Once again, measurable difference in engine smoothness, especially at idle but no change in the intermittent surge or hesitation. I also removed & inspected the BBS, then reset them to 2.5 turns out. To this day, I have done no further airflow sync beyond this (though I probably should). I also replaced the aftermarket K&N filter with the proper Mahle paper element and performed an oil change with Mobile 1 15w-50 synthetic & Mahle filter.

3. The ignition:

I decided to check valve adjustment - they were spot on. When I pulled the head covers, I noticed small cracks and rubber degradation on the spark plug leads. I also read that an intermittent ignition coil could cause similar issues. Finally, after the bike stalled one day, I pulled the plugs and the left plug was wet with gas. Also, the plugs were Bosch dual electrode, not the esteemed Autolite recommended by so many of you. *NOTE* BMW parts are EXPENSIVE - eBay is your friend! To rule out any and all ignition issues, I purchased a used eBay ignition coil, new Autolite 3923 plugs and new aftermarket EnDuraLast reinforced silicon wires from Euromotoelectrics (so incredibly high quality at such a better price than OEM - the “reinforced” ones are the ticket, they work with the OEM puller tool). After installing these parts, the bike ran better and smoother than I ever thought possible...UNTIL...the hesitation occurred again as I was getting on I-95. I played with it. It seemed to be only in a certain part of the throttle (1/4-1/3) - or at certain RPM (~3000), and definitely seemed better and more predictable than before. I could replicate it by going back to that throttle position at that speed. It happened much less on back roads at low speeds.

My belief is that there were issues with the HES and ignition system that were compounding and obfuscating the root problem, which were resolved with the above. Keep reading for the root cause!

4. Throwing parts at it

Frustrated, I thought back to the maintenance records. I don’t ride in inclement weather, but previous owners had reported problems in the rain. Was it the placebo affect, or did I notice more problems on humid days? Ahhh!!! On eBay, I purchased a full 1999 R1100R wiring harness complete with a loaded fuse box and proceeded to swap out every single relay and fuse in the bike. Again, I had several trouble free rides but the hesitation reoccurred, again in a very narrow band of RPM/throttle conditions and again replicable. Part of the perception of increased replicability was likely due to more frequent highway riding as I became more comfortable on the bike - as we all know, on the highway it is much easier to maintain a static throttle/speed condition for a length of time.

I read about the “dual wiper” TPS and fantasized that the low throttle opening wiper in mine might be malfunctioning - this could be why it “caught” when the throttle was opened further? No, as it turns out my TPS was fine. It and the throttle bodies look brand new, so I had trouble imagining they were the problem. Thank goodness I restrained myself from messing around with it - doing so would have eliminated a valuable baseline.

5. What’s it thinking?

I read a post about the O2 (Lambda) sensor, its role in the Motronic 2.2 and closed loop vs open loop. A light bulb went off. Was the O2 sensor feeding the Motronic bad data??? I inspected my O2 sensor and felt a building sense of excitement as I discovered frayed wires leading into a broken, corroded cap. I read the posts on Motronic fault diagnosis, broke out the analog DC meter and read the codes - the expected 1122 and 1133 HES codes were present, along with 2342 “Lambda sensor value is invalid”. Bingo...I reset the Motronic and rode again - 2342 reappeared. I ordered a new O2 sensor, removed the tank to install it, routed the wire away from the cat, reinstalled the tank, pulled fuse #5 to reset the Motronic and started the bike.

Right away, there was a difference - previously, on a cold start with the obligatory throttle advance lever set, the bike would jump right into a 1300-1400 RPM high idle for 25 seconds or so, then cough and struggle down to 800-900 RPM for 10 seconds or so. It would then recover and run normally. After the new O2 sensor was installed, this “cough and struggle” cold start routine no longer occurred. I was confident I had fixed the problem. I got my helmet & leathers, jumped on the bike and left the driveway. It was utterly unridable. Any attempt whatsoever at acceleration caused the engine to fall flat. I limped back and pulled the Motronic codes. None other than 1122 & 1133. WTF???

6. Wait, what’s it really thinking?

I had since acquired an E38 740i and spent some time reading about and understanding fuel trims and adaptions as it relates to the M62TUB44 BMW V8. That engine, like most modern fuel injected motors, knows a lot. It measures the mass of the air entering the engine, which allows it to calculate and inject the exact amount of fuel required for the correct stoichiometric mixture. It measures the output of each bank of cylinders individually and adjusts the fuel injection trim for that bank independently. It has individual computer controlled ignition coils on each cylinder, which allow it to see and react to individual cylinder ignition events.

The oilhead 1100 is not so smart. It does not measure air mass, only air temperature. It also does not differentiate between the cylinder “banks” in any way - it fires both spark plugs and both injectors simultaneously, measures the COMBINED output of the cylinders with the O2 sensor and makes its adaptions accordingly, which is undoubtedly why balanced throttle body and valve lash settings are so critical. If the O2 sensor stops working, it ignores it and runs on a fixed map instead. This explains why it ran better with a faulty O2 sensor and terribly with the new one.

I knew airflow was reasonably even, since the bike ran fine unless the issue occurred. I knew the O2 sensor worked and that the HES and ignition components were new. I knew the fuel pump, filter, lines and tank had all been recently serviced. What was I missing?

I came across some posts referencing Bosch EV14 injectors and a retrofit kit for the 1100 oilhead. Then it hit me. I had a defective injector, which malfunctioned intermittently at certain pulse widths - likely fouled by whatever caused the tank to need relining and the fuel pump to fail twice! I had already read many accounts of vastly improved performance in the 1st gen oilheads by swapping the original EV1 injectors for the EV14 models and it wasn't hard to believe that 20 years of innovation had some kind of positive effect on fuel injection technology so I needed little convincing. I ordered the EV14 flow matched injector kit from tills.de, waited a week or so for it to arrive from Germany and installed it.

What a night and day difference!

Everything you read about the benefits of these EV14 flow matched injectors is true. No longer is the “cold start” throttle advance needed. The engine fires instantly and settles right into its proper 1100 RPM idle, smoother than I could have imagined. Throttle response is sharp, instant and brutal - much closer to my previous Moto Guzzi Griso 8v. Engine vibration, especially above 3500 RPM is night and day - 5k RPM is now smooth as can be. The intermittent hesitation is absolutely GONE!!!

7. The oil leaks:

I were convinced these were the result of the original plastic sight glass weeping. Though I sourced a spare and still intend to replace it, it was not the leak source. After a thorough cleaning and a few more miles, I determined the engine case was seeping oil on the center seam. I found a forum post which recommended snugging up the bolts while being VERY careful not to strip the delicate aluminum threads (this is a common “thread” throughout this bike - another great recommendation I read was to use ONLY the supplied BMW tool kit, which limits the applied torque by design). After doing this, it runs dry as a bone.

8. Other stuff:

The bike had a rattle and unsteadiness in the front suspension. I suspected the shock absorber, but the problem was actually the rubber bushing which mounts the shock to the frame at the front under the gas tank. It was totally destroyed and mostly gone - replacing it was inexpensive, quick and greatly improved the feel of the bike. I also replaced the weeping fork seals, which were equally simple and inexpensive. Last but not least, occasionally the engine experienced a second of timing chain slap when started. A new revised left OEM tensioner resolved this 100%.

I installed chrome factory BMW head covers from Sierra BMW, which I absolutely love. They complement the chrome theme of the R1100R without making it look like an 1200C and are very uncommon. I also added a Gerbing single temp controller to run my liner and gloves, which blends right in mounted to the TPS with some black Velcro. Finally, the bike had a cheap vinyl aftermarket seat cover on the rider seat and a different aftermarket cover on the pillion seat. I found low mile perfect condition factory original R1100R replacements on eBay. I have Spiegler black/chrome stainless brake lines waiting on the shelf for the next time I get a night in the garage.

Hope this helps someone! Ride Safe

John
 
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Thanks and welcome to you. We very much appreciate the time you took to share this information. We all learn together here. Even me, a non mechanic!

Voni
sMiling
 
Thank you for the kind words Voni and 8ninety8 - I wanted to get it all down while it was fresh! It’s been a fun year learning - these are amazingly well engineered machines, so DIY friendly and with such a dedicated enthusiast following.
 
oconcon,
You are now my best friend!
I bought a 1998 R1100r in July, and being new to BMW oilheads, I have bravely set out to make my bike purr.
Fortunately mine was in good shape when I bought it, but I have the valves and throttle bodies now spot on, it has that sewing machine feel on the highway, with instant throttle response.
My Speigler brake lines are on the way, and I will address the HES sensor next. My biggest unknown was buying one and having the same inferior wire insulation, I want to do it once, correctly, and have that out of the back of my mind.

All the best,
Cam
 
oconcon,
You are now my best friend!
I bought a 1998 R1100r in July, and being new .......... I will address the HES sensor next. My biggest unknown was buying one and having the same inferior wire insulation, I want to do it once, correctly, and have that out of the back of my mind.

All the best,
Cam

The best advice I can give for that is to contact GSADDICT on this forum. You remove your HES and send it to him. He will rewire it with the correct high temperature wire and you will never have to concern yourself with it again. If you have more questions, you should start your own thread about it and not highjack this one.
 
oconcon,
You are now my best friend!
I bought a 1998 R1100r in July, and being new to BMW oilheads, I have bravely set out to make my bike purr.
Fortunately mine was in good shape when I bought it, but I have the valves and throttle bodies now spot on, it has that sewing machine feel on the highway, with instant throttle response.
My Speigler brake lines are on the way, and I will address the HES sensor next. My biggest unknown was buying one and having the same inferior wire insulation, I want to do it once, correctly, and have that out of the back of my mind.

All the best,
Cam

Cam, nice to 'meet' you and congrats on the R1100R! Regarding sewing machine feel - exactly! I love tilting an ear to one side and the other to hear the timing chains and top ends singing in perfect harmony. My guess is that even though mine feels perfect to me now, an hour or so with a set of carb sticks would offer further refinement...

m_stock10506 -

I believe Cam referenced the HES rebuild because of #1 in my original post. As i mentioned, I sent mine to off to Cata Dan for a similar rebuild and was very pleased both with the finished product and his communication & insight along the way. I'm sure GSADDICT offers the same :)

- John
 
Welcome to this forum and thanks for the detailed post on your 1100 purchase and subsequent mechanical adventures! I have not seen such a great step by step description of a dedicated new owner getting to the bottom of these all too typical problems. I enjoyed reading it. Twice...

Well done! :thumb
 
"I came across some posts referencing Bosch EV14 injectors and a retrofit kit for the 1100 oilhead"

THAT really got my attention.... I need to do some research....
 
"I came across some posts referencing Bosch EV14 injectors and a retrofit kit for the 1100 oilhead"

THAT really got my attention.... I need to do some research....

I have the tills.de injectors on my 1100RT along with an LC-1 fuel injection controller that allows me to run any AFR I want. Between these two mods the bike barely surges at all now. The fuel injectors did not help with the surging on my bike however they definitely enhance throttle response and engine smoothness. I noticed it immediately. Going from a two pintle stock injector with a spray pattern that resembled peeing to a 4 pintle modern injector with WAY faster open/close times made for a much smoother motor overall with better response. The spray pattern is a "mist" type of spray and this means the fuel is atomized much better and will burn better. Definitely a worthwhile mod.

I am 100% convinced that not all 1100 engines were created equally. I've worked on some that did not surge at all and then there was mine. The surger from hell. It took me a couple of years of tinkering and doing every single suggested mod and tuning technique I could find. Working with Roger04RT on testing his solution on my 1100 educated me to a lot of the nuances of oilhead fueling and fuel injection in general.

But SOME of these 1100s really are way worse than some others. I have no explanation for that other than the tolerances of _something_ is not the same across all engines. I suspect they may have different fuel maps in different versions of the ECU EEPROM but now that I am retired from the electronics and semiconductor industry I don't have access to a reader or programmer to compare them. But I would bet that the chksum on them is not identical. I also note there was some outfits making new fuel map chips for them as well. There's a lot of "moving parts" in this system so it's not an easy puzzle to solve.

The AF-XIED has made these bikes a joy to ride again though and we have Roger04RT to thank for that.
 
The AF-XIED has made these bikes a joy to ride again though and we have Roger04RT to thank for that.

My twin spark 1100 hardly surged at all but the addition of the AF-XIED brought some much-appreciated smoothness and improvement to throttle input. Thanks to Roger for developing and Happy Wanderer for guinea-pigging, er, beta testing. :thumb
 
Happy Wanderer - I’ve enjoyed reading your threads and your evaluation of the tills.de EV14 kit was a deciding factor for me :thumb.
 
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