2010 (DOHC) R1200GS Engine Vibration

lkraus said:

Also throttle sync is an issue at and just above idle, above that the ZFE adjusts mixture based on the O2 sensor readings.

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I'm not understanding this too well... let me think it out out-loud:

At idle the sync is handled by the stepper motor bypasses. The throttle plates are actually fully closed (unlike oilheads) at idle. Right off idle is where the sync is most easily checked, since the amount of difference between the two TBs is a larger proportion of the total airflow - meaning it's easier to see. The actual sync should retain whatever offset there is (if any) throughout the range of throttle opening - if your cables are good and the junction box is good. Which is why we suggest adjusting the sync (if needed) just off idle (between 1,200-1,800 RPM.)

BMW's instructions - if you can decipher them on the REP-ROM are to note the amount of offset in an actual value at idle, and maintain that offset (not percentage of offset) throughout the throttle range. IE - if the right side offset is 0.01mBar at idle - then at 2,000 RPM the offset AMOUNT should remain the same. If the left side read a total of 1.00mBar, then the right side should be 1.00mBar + 0.01mBar for a total of 1.01Mbar. In my experience, if the valves are adjusted correctly - you can come fairly close to perfect throttle-body balance over the full range of engine RPM (mine is very close) at least on the hexheads. Dunno on camheads - haven't done one.

While the O2 sensors do correct mixture (most of the time) - this is really a separate function from the throttle body balance. There are two O2 sensors - one for each cylinder, and even if the throttle-body balance is out, the ECU will correctly adjust the mixture for EACH cylinder for whatever amount of air is in the combustion mix.

The O2 sensors DO adjust the mixture at idle - this is easily seen on the GS-911. The heated sensors used on the hex/cam-head are quite fast to start working (within about 15-20 seconds of when the engine is started), and you can then observe the output switching hi-low using the GS-911 plotting feature. The switching is an indication that the ECU is adjusting the mixture (if the O2 sensors saw a constant mixture at idle - they would have a constant output.)

The vacuum hose that goes to the left throttle body is the one from the purge valve for the charcoal canister. The electronic purge valve only opens under certain engine conditions. The amount of additional air introduced to the left side throttle body is small in comparison to the amount of air that is flowing through it at the RPMs in question. While it might seem to introduce a small imbalance - I suspect it is really not a major contributing factor to the vibration. It's simple enough to check - just disconnect it and cap off the input port on the throttle body. If the vibration is reduced enough to be noticeable - then you've found one smoking gun. FWIW - my charcoal canister was in the way of adjusting my front shock, so it's been on the shelf and I just haven't gotten around (in 76,000 miles) to putting it back on. I did cap off the throttle body, and did a bit of re-routing of the hoses so the tank vent now goes to a vent hose near the left footpeg.

The goal of balancing the TB's is to get an equal amount of power from each cylinder on each combustion cycle. This is when the engine runs the smoothest with the least vibration. The amount of air going into the cylinders should be balanced in order to help achieve this. The amount of fuel going into each cylinder should also be balanced, and the valve openings should be the same. All of these will have an effect on the combustion balance of the engine (as can other things such as bad ignition, or carbon buildup resulting in different compression in the cylinders.)

Dunno about the bottom coils/plugs only being used at lower RPMs, I've never seen anything about this. Just noodling in my head - since the purpose of the two plugs is to help start a larger flame front on the ignition of the compressed mixture, to my way of thinking, this would be equally important at higher RPMs as at lower RPMs. But that's just noodling - don't mistake it for any sort of factual data.

Clearly, I did not put enough thought into what I was saying about the throttle balance. Ignore that part of the post.

I've looked for more info on the lower coils instead of relying on a fuzzy memory of what someone might of posted. The best I can find is this from the 2004 press release on the R1200GS:

"Featured in all BMW Boxers since 2003 (with the exception of the 850cc power units), dual ignition has been further modified and improved on the R1200GS. The auxiliary spark plug is now arranged at the outer edge of the cylinder, the ignition timing of both plugs being freely programmable as a function of load and engine speed in order to further optimise running smoothness, emission management, and fuel economy. Referred to as "phase shift", this adjustment process is maintained consistently all the way from part load to full load.

In practice, this means different ignition timing points on both spark plugs in defined control map areas. When approaching full load, where dual ignition no longer provides any benefits, the phase shift effect is so large that the spark crosses over on the auxiliary plug in the expansion cycle (60 degrees at TDC). For all practical purposes this corresponds to single ignition on the central spark plug under full load."

I think the idea of the lower plugs not firing comes from that last paragraph. Apparently, under full load, they fire so late that they are not contributing to power production? Now I'm wondering if 4-5K rpm cruising would be considered "full load"? If not, the lower coils may indeed be needed to keep the engine running smoothly at those speeds.

lkraus said:

I think the idea of the lower plugs not firing comes from that last paragraph. Apparently, under full load, they fire so late that they are not contributing to power production? Now I'm wondering if 4-5K rpm cruising would be considered "full load"? If not, the lower coils may indeed be needed to keep the engine running smoothly at those speeds.

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I have no real information as to what the author meant by "full load" but would be shocked if any automotive engineer considers an engine toodling along steady state at 40% to 50% of redline as full load. Typically full load would be at a lower rpm when the throttle is suddenly fully opened, or for that matter, at any rpm when the throttle is opened so that the engine is seeking to increase rpm as quickly as it can.

strmboui05 said:

I am not sure if I said in this thread, Pull in theClutch and off the throttle and coast at 80 mph bike, handle bars, footpegs go dead smooth.

Last night tried this coil stick test:
Disconnect the lower coil connection from EACH side so you're only running on the main plug on each side. If the bike fires and runs ok (if one of the main coils has failed completely the bike will only fire on one side) then take if for a quick 5 minute ride, and make the engine labour by using a higher gear than normal to check if one is failing under load. If all is ok reconnect the lower coils and then do the same procedure with the main coils.
Each time the the engine ran great even lugging in 5th qand 6th for both top and Botom coils. Had a buddy repeat the same procedure and same result stong pulling, no hesitation, no chug, no coughs, no misses, no backfire.

I didn't realize that it would run so well with the top Coils unpluged.

Running out of ideas. I will check all touques on engine/frame/gas tank/etc.

Send me your ideas, I'm all out!
rac

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Thank y'all (that's Texan for "you all") for the replies!

When I performed the above stick coil test the outcome was significantly different. There might be a difference between '09 and '10 models? On mine the bottom coils only worked up to 40-50 mph. Who or how could one find the answer to that question?

Bypassing the charcoal canister and plugging the test port was definitely an improvement for my bike. After a 250 miles ride yesterday, it was an easy decision. Maybe the solenoid failed in the open position because it is open at idle. Either way I have removed the canister and rerouted the vent tube and capped the valve. That takes care of that!!

Some food for thought..................The fuel mileage on my bike when running Interstate speeds (75-80 GPS indicated) is around 30-32 mpg. Not the best. My bike has been modified to fit me. Me is 6'7", 270 lbs all geared up. My custom seat is 1" above stock. The windshield is 4" taller and wider than stock, etc. At 55mph I get 48-52 mpg. Translation into usage per hour: At Interstate speeds my bike uses almost 3 gallon per hour and at 55mph only 1 gallon per hour. I guess one could make the argument that power output at Interstate speed is 3x higher and that equals more vibrations also. Fuel usage/hour versus load or power output should be fairly linear. The question is how does this tie in with the bottom/top stick coils if any?

lkraus said:

I've looked for more info on the lower coils instead of relying on a fuzzy memory of what someone might of posted. The best I can find is this from the 2004 press release on the R1200GS:

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I just found this thread on advrider. Inmate StepToe made some good comments about trouble shooting stick coils on R1200 series bikes.

http://www.advrider.com/forums/showthread.php?t=946092&page=2

His comments go with other peoples findings. The poor guy ends up beating his head against the wall! Based on that I ordered new stick coils. Fingers crossed!

5_19 said:

Thank y'all (that's Texan for "you all") for the replies!

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They speak funny in Texas. Once when visiting Georgia I was informed (after apparently using y'all incorrectly) that y'all is singular. The plural form was "all y'all". By those rules you should have written "Thanks all y'all"...

I hope the coils solve your issues. With respect to your MPG numbers they are not that surprising to me given the taller and wider windshield. My standard '05 GS with a cut down windshield would get around 42 MPG at 70 MPH. That would drop to 36-38 MPG at 80 MPH. The windshield may have been cut down but the addition of touratech Zega panniers didn't help any. I was surprised by MPG in the low 30s fighting a desert head wind one ride.

marchyman said:

The plural form was "all y'all". By those rules you should have written "Thanks all y'all"...

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You are absolutely right, I stand corrected....... LOL!

y'all got it wrong.

I looked it up in my Texas dictionary. Y'all is plural. It is used when addressing a few, or small group.
All y'all us only used when addressing many.

As in all y'all yankees are like hemorrhoids, and such like. It is the equivalent to "yous guys". And vibrating Beemers are
very irritating, so I hope you let usens know what the cure ends up being.

I have the same problem as the OP of this thread. 2010 GSA running great until 40,000 km and all hell broke loose. I was riding on the highway and it felt like riding in cobblestones. Started with the easy things. Changed my tires, set the valves , changed the plugs. Checked the stick coils an 02 sensors. The dealer changed the injectors and throttle actuators and then all the cables at the Bowden box. No change!
My next concern is that something mechanical in the engine has gone out of balance and this will never be resolved without an engine change. Or, possibly Carbon build up on one piston ? It is constant, consistent, vibration . I have no trust in the dealer resolving the issue. I think any minor imbalance in the boxer engine will result in annoying vibration. I'm just about done unless someone can magically solve the problem

gpw1200 said:

I have the same problem as the OP of this thread. 2010 GSA running great until 40,000 km and all hell broke loose. I was riding on the highway and it felt like riding in cobblestones. Started with the easy things. Changed my tires, set the valves , changed the plugs. Checked the stick coils an 02 sensors. The dealer changed the injectors and throttle actuators and then all the cables at the Bowden box. No change!
My next concern is that something mechanical in the engine has gone out of balance and this will never be resolved without an engine change. Or, possibly Carbon build up on one piston ? It is constant, consistent, vibration . I have no trust in the dealer resolving the issue. I think any minor imbalance in the boxer engine will result in annoying vibration. I'm just about done unless someone can magically solve the problem

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Mine was kind of gradual and just seems it kept getting worse. What happened at 40,000km? Was it after service etc? Where are you located?

5_19 said:

Mine was kind of gradual and just seems it kept getting worse. What happened at 40,000km? Was it after service etc? Where are you located?

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At first I noticed my windshield vibrating more at a light, then the highway ride that felt it was on cobblestones. It wasn't after service and I didn't do much to the bike. After each attempt the dealer makes all i have to do is rev it a bit and I know the issue is still there. They are very frustrating to deal with as they don't know what they are doing and they eventually start trying to make you believe there is not a problem.
I know my bike and I know there has been a significant change. The service manager always told me these engines get smoother as they get broken in. Now he tells me at 40,000 km this is what I might have to expect. He changes his story to suit the situation. I am going to force him to ride another camhead and then jump on mine. I worry he is such a liar that he'll say "it's within the tolerance we are allowed for vibration"
This is not a typical boxer vibration, I know what that feels like. This is a constant high frequency deal breaker vibration.
I have no respect for his opinion anymore. I'm giving them one more chance and then the bike will be traded in for a Triumph Explorer XC. I'm done with BMW. I'm in Toronto, Canada.
If it is an engine unbalance situation I can guarantee they will never find this, never mind solve it.

5_19 please let us know if the stick coils make a difference.

As a footnote, isn't it sad we need to rely on other riders to fix problems ? Shouldn't the manufacturer have the knowledge to deal with this ? It's gotten me so stressed I just want this problem to go away.

Vibration under power in a twin engine has a couple possible sources:

1) Unequal combustion power
2) Something mechanical in the powertrain

If you let off the throttle at high speed and coast (clutch still engaged) and the vibration goes away, and if you coast with the clutch disengaged, and you have no vibration, it seems like it has to be unequal combustion.

Once you know the stick coils are good, and that compression is equal and that the valves are correctly set, you're down to a couple items.

1) Throttle butterflies under power are at different angles. Plug the canister lines at the TB temporarily and equalize with the throttles well off the stops using the right hand adjuster.

2) the BMSK, which has dual independent Mixture Adaptation, does an excellent job of equalizing AFR (meaning fueling), has corrupted adaptation tables. For the OP I'm suspicious of this because it happened after a re-flash. I would reset the Adaptives with a GS-911 and verify both LCFs and O2 sensors were working with a GS-911.

3) The tank vent solenoid only goes to the left TB and it opens and closes on a timer. The valve inside the solenoid is supposed to open less at idle than at WOT. It has a spring that counteracts the high pressure differential at idle. I suppose this valve could get messed up and stay too far open. That's why I'd try riding with both TBs plugged for a while, to see if maybe something is wrong with the valve.

4) I would also have the GS-911 park the idle actuators in their lowest position and make sure there was the specified amount of slack.

With equal air, and working O2 sensors, the BMSK should be able to equalize the power.
RB

I have a Canadian bike which never had a canister. The tech changed the Bowden box components and the sync is dead on. Everything else is functioning as it should. All the ignition components were checked by me and two independent BMW techs.

On the highway I pulled the clutch in and the vibration disappears. Rev the engine and I feel them again .

My only thoughts now are there may be carbon build up on one piston head, which is a longshot.

The other is the engine is mechanically out of balance. I don't think they have a way of measuring this though.

I can see them finding "no fault" and whining that they can't fix a fault they can't find. I keep asking them if severe vibration is not a fault ?

Unfortunately technicians, like doctors, just want you to go away if they can't find the problem. It's called the GOMER policy. Get Out Of My Emergency Room. They will then lie and deny .

Does anyone know a way to determine a mechanical imbalance in the boxer engine ?

gpw1200 said:

Does anyone know a way to determine a mechanical imbalance in the boxer engine ?

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Many many years ago I saw an article by a HD mechanic who shone a pinpoint flashlight at the HD's rear-view mirror and watched the reflected patterns on the wall of his shop - he claimed to be able to tell what was out of balance by the pattern produced. I always thought the article was pretty much BS - but aside from something like that, short of disassembly and measurements, I don't know of any means to track down a mechanical imbalance on any engine.

You might spend a bit of time with a mechanic's stethoscope and your bike and one that runs well, and see if there are any odd mechanical noises coming from any area of your engine. (Harbor Freight has a dandy stethoscope for $3.99 - sometimes on sale for $1.99.. great tool, and one I use frequently.)

As Roger pointed out - the BMSK should do an adequate job of making the engine make equal power from the cylinders. To check it, I'd look at the O2 sensor output using a GS-911 and make certain the patterns look similar port/starboard cylinders. If one looks significantly different - first I'd swap the O2 sensors and see if the odd pattern follows the sensors - if it did, I'd replace the one with an odd pattern (by odd - I mean excessively slow switching - should be on the order of 1 second or so - or low output.) A bad O2 sensor will not cause any fault to be stored in the BMSK, so if the dealer's mechanic isn't really tech savvy (some rely on the machine to tell them what to do) - they could have missed this. Dunno if the factory computer shows the actual O2 sensor pattern or not, that might be something the GS-911 has and the factory box may not.

I realize you have replaced the O2 sensors - but the only mechanical fault I found in my bike was the routing of the wiring going to the port side O2 sensor. It was mounted so it rubbed against the back of the transmission case. It eventually wore enough to ground the output from the sensor - intermittently. Took quite a while to track this down - something like that could have happened - which is why the GS-911 is so handy to have.

Other than that - I can easily understand your frustration. I had an '04 R1150RS that was a lovely bike in all respects - except - it had a buzz in the engine that made it impossible for me to ride any distance without being in severe pain in my hands. Nothing I did made it go away, and I did a LOT of things. I finally traded it in for my current R1200R - which is wonderful as far as vibration. The dealership that took it in trade resold it 3 times after I traded it in - it seemed no one could stand the bike for long. Dunno what eventually happened to it, but I was certainly glad to see the last of it.

+1 to Don's advice.

You could also use your GS-911 to reset Adaptive values and see what it is like and how the vibration progresses: more or less or the same after resetting.

I asked them to change the O2 sensors and stick coils ,as they ran out of ideas. They will not do it unless their little computer tells them they're faulty. At this point I doubt that's the problem as well, and I'm done with this. Life's too short.

The adaptive values were reset numerous times. Didn't make a lick of difference.

The O2 sensor plots look exactly the way they should and are identical.

gpw1200 said:

I asked them to change the O2 sensors and stick coils ,as they ran out of ideas. They will not do it unless their little computer tells them they're faulty. At this point I doubt that's the problem as well, and I'm done with this. Life's too short.

The adaptive values were reset numerous times. Didn't make a lick of difference.

The O2 sensor plots look exactly the way they should and are identical.

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Then it sounds like the O2 sensors are fine and that it is not the adaptive values going awry.

If you have access to a GS-911, and can connect it, set it up to log values to a CSV file on your PC, then start the bike without touching the throttle, and let it idle like that for 5 minutes. Close the file. I would be happy to look at it.

Have you tried pulling the tank vent hose from the left throttle body, capping the TB nple and going for a ride? Could be something wrong there.
RB

Re-visit of the Lambda Sensors

Looking to test the Lambda sensors by using volt meter and heat gun. Been reading about this Cam head engine vibration problem around the world, UK South africa, Germany, Canada. One of the guys in South Africa had got his dealer to swap out the Lambda Sensors even though the BMW computer showed no fault codes and it worked. Vibration gone smooth runnings again. It took a few letters to the current BMW Motorcycle business director and he lit a fire under the local dealer. So, re-visiting the Lambda sensor again.

Any one know of an after market Lambda Sensor replacement for the BMW ones. for the 201-2012 Cam Head part# 11787718140 and printed on the inside of the sensor under the threads NTK:JAPAN-9G21. Can't find a hit on these for a replacement part. $240.00 a piece is steep but if it runs again it is worth it!

Any help is appreciated.
Thanks,
rac

In order to test them for accuracy you need a source of specific air/gas type and control O2 sensor temperature.

Another way is to put them in an exhaust with a second bung added and compare each sensor with an LC-1. If you wanted to send both of them to me, I can do it.

This is a perfect replacement but you have to cut and splice with posilock connectors. $79 at Beemerboneyard.

http://www.beemerboneyard.com/11781464492n.html

I will be surprised if lambda sensors solve your problem.

What do you suggest?

Roger 04 rt,

If you don't think it is the Lambda sensors do you have a different suggestion? I started this thread a while back and another on ADVrider. This thread seemed to have more concious thought as it progressed. So I am open to suggestions because I would rather be riding than fixing and this BMW is starting to resemble a "Hanger Queen"!

Please, I am listening!

Thanks,
rac