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2012 RT Intermittent Stuttering/surging Running Problems

var1200rt

New member
I have a 2012 R1200Rt with 48000 miles. A few times over the summer I notice the bike stumble or surge. After this happened, everything ran fine. Maybe about two months later it happened again. Then everything was running ok.

I has new tires installed at the dealer about 4 weeks ago. The dealer is 45 miles away by interstate. On the morning I went to the dealer, I was about 1/4 mile from my house and after stopping at the stop sign, I went to take off the the bike stuttered when I started accelerating. It cleared out almost immediately, and then ran fine. got on the interstate and was moving with traffic 80-85 mph, everything was good. Got my tires installed, came home. Right before I got off the interstate, I had to get on the throttle to get around some cars, and the bike stuttered at high RPM's. and cleared almost immediately.

I thought the plus or throttle sync might be off since it was time for the 48K service. Did the service, new plugs (old plugs looked normal) new air filter, did the throttle sync, it was out, valves check out in specification.

The following morning, I left to go get some 93 ethanol free gas. At the leaving the stop sign, the bike stuttered, then surged,stuttered and surged. It was bucking like a horse. Then it cleared and ran fine for a nice 200 mile ride.

Now it seams like the first ride of the day, it will stutter within the first 1/4 mile and then be fine the rest of the day, no matter how many times is cut off and restarted. The bike is kept in a garage. Temp in the garage this morning was 55 degrees, it was 28 outside. This has me a little worried since this is happening almost every ride. Any suggestions?

Thanks
 
Do I need to do more than drain the tank and add fresh fuel and and a fuel treatment like HEET? Thanks

I would get a bottle of Isoheet in the Red bottle and put half of it in a tank of fuel. That is usually sufficient to absorb the water and mix it with the fuel.
 
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Mine does that from time to time. It evens stalls. I found that running Seafoam through it a couple of times a year keeps it under control.
 
Water in your fuel is the easiest and first thing to check. If that doesn't clear it up consider that it could also be an intermittently defective fuel injector. Fuel is under pressure behind the injector (an electric gate) which opens when the bike control computer tells it to. If it operates erratically you'll have the symptoms you describe, which I would expect to post an error you could read with a diagnostic device. I have had this problem in the past with some car engine injectors. They usually didn't just fail outright, they just degraded or performed erratically/intermittently which can be problematic to find in the absence of an error code.
 
2015 1200GSA developed a habit, when stopped and blissfully idling, of RPM increasing to 4000 and surging/pulsating. Could barely get it to limp across the intersection, no ability to get RPM to increase. Turning the ignition off and then on again resolved the problem...until the next stop. Happens whether I'm in neutral or first gear, stop light or stop sign. Particularly inconvenient when followed by impatient drivers. This developed while on a trip from UT to ID. I had to leave the bike in storage for several months. When I retrieved it in September, there was no issue, but since shipping it home to central FL, it returned. IN September a GS-911 scan showed a "Level 2 monitoring of throttle valve 1, setpoint exceeded. The fault is not present now"

Any ideas or advice would be appreciated. For reasons unrelated to this issue, I'm planning to sell the bike, and plan to have this resolved beforehand. Thanks
 
Water in your fuel is the easiest and first thing to check. If that doesn't clear it up consider that it could also be an intermittently defective fuel injector. Fuel is under pressure behind the injector (an electric gate) which opens when the bike control computer tells it to. If it operates erratically you'll have the symptoms you describe, which I would expect to post an error you could read with a diagnostic device. I have had this problem in the past with some car engine injectors. They usually didn't just fail outright, they just degraded or performed erratically/intermittently which can be problematic to find in the absence of an error code.

There IS a way to test/clean the injectors that is fairly simple...

I made up a test rig out of wood that is essentially a wooden ‘L’, with a hole drilled in the upright portion to hold the injector.

I then made up a wiring harness with a 9V battery connector, a pushbutton switch and two leads with small barrel connectors that attach to the injector leads.

I then went to a farm supply store and got a large plastic syringe (no needles needed), and scrounged a piece of tubing that goes from the syringe to the injector.

Mount the injector in the test rig. Fill the syringe with injector cleaner and place a piece of cardboard in front of the injector nozzle so you can see the spray pattern.

Push hard on the syringe plunger to pressurize the hose and tap the button on the harness to fire the injector...now look at the spray pattern.

Repeat to run several syringes of injector cleaner thru the device.

I did wonders for the RT I was working on...


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I did get a bottle of Isoheet in the Red bottle and some Seafoam. I had less than 1/2 tank of gas but I added the Isoheet and Seafoam. I then rode into work the following day and back home. No issues. Virginia did get hit with a batch of cold weather with ice and snow so that stopped the riding for several weeks. Took the bike out Sunday, no issues. Ran the tank almost dry and filled up and added the Isoheet just to make sure. Rode into work this morning, no issues with the bike. Thanks everyone for the assistance.
 
I put a few a little Seafoam in the tank every fill up unless on an overnight. I dont know how long it will be when I ride again, especially now that I am not commuting daily. I know I won't have water issues and it might help keep things a bit cleaner. I don't carry it with me. I also fill up at Shell or Chevron stations with high volume sales. 76 too. That way you're likely to get clean fuel to begin with and they have better controls regarding credit card skimmers. Probably would not hut to carry a little on a tour just in case.

I also use Marvel Mystery Oil just before an oil change, in the crank case.
 
Well the issue came back on a trip but much worse. On the return of a several day trip the bike was running fine until I stopped for lunch. After stopping the bike was surging really bad I would stall when engaging first gear. I had to rev it to 4000 rpm to get moving. Not good for the clutch. I was 180 miles from home. I got gas and only had two stoplights to get on the back road. Once I got there the bike ran great and got 48 mpg. When I got off the interstate the bike died. I got it restarted and it did not want to run. I only had two stop signs and 1/2 mile to go. I made it to my drive and the bike died. It would not run and I had to push it up the drive. Later that night I disconnected the battery for 5 minutes and after reconnecting, the bike ran perfect. Next day I rode the bake and after about 10 mikes it stuttered while riding (3000 rpm). That is new, it was always at idle. took the bike home and its parked. If it stutters in a turn I could drop it.

The bad news is after I called the dealer and they confirmed this is not a usual issue for a Camhead, the said they are backed up in the service department until June 18th. They have a full staff it just they are a very good dealer and people are skipping other dealers to go there for service.
 
well thats just a total drag, sorry you are continuing to have problems

on older VW vanagons and late 70's FI VW buses there is a cylinder head temp sensor which if loose can cause really odd but drastic running conditions, intermittent with no logic to it

when screwed tightly into the head, no problems ever
 
Unlikely you picked up that much more water, but it depends on where you were traveling.

I assume you have enough slack in the throttle cable? All the vacuum hoses are connected correctly?

Did you reset the throttle positioning sensors when you reconnected the battery? (Turn ignition to on but don't start bike. Slowly open the throttle wide open then closed, open/closed a total of three times)

Bad coils could be an issue, but I'd assume it would be unlikely that several would go bad. I think the secondary coil is used during lower RPMS and then the primary takes over at higher?? You could swap/reseat them just in case.

Have a friend with a MotoScan or GS911?
 
...Bad coils could be an issue, but I'd assume it would be unlikely that several would go bad. I think the secondary coil is used during lower RPMS and then the primary takes over at higher?? You could swap/reseat them just in case.

Have a friend with a MotoScan or GS911?

All four coils are in use at low rpm. As rpms rise, the timing on the lower coils shifts nearly 180º, and they don't contribute much to combustion. A loose coil wire on a primary coil produced intermittent hesitation and stumbling above ~3500 rpm on my RT, especially under acceleration. It ran normally at lower rpm or under light load. One way to check would be to disconnect a suspect coil, if the the bike runs worse that coil was good, if there is no change you found the problem.

I have not suggested coil trouble because apparently the problem has occurred while starting from a stop and required high rpm to get moving, which is quite different than the trouble I experienced.
 
On my 2010 RT I had a intermittent misfire/stumble. I would be riding down the expressway on cruise, at a steady speed or accelerating and there would just be a brief stumble or feeling of a brief misfire. It was VERY intermittent and I saw no errors when I checked for codes with my GS-911. I tried injector cleaner and had synced the throttle body. Had about 60K. I replaced all the coils and spark plugs at the same time and it resolved the problem. I had done research on this and this seemed to be one of the causes of this and I finally decided to try it and that was the fix for me.

This is a source of BMW stick coils that would be an alternative to a BMW dealer:

https://www.euromotoelectrics.com/category-s/1754.htm
 
Unlikely you picked up that much more water, but it depends on where you were traveling.

I assume you have enough slack in the throttle cable? All the vacuum hoses are connected correctly?

Did you reset the throttle positioning sensors when you reconnected the battery? (Turn ignition to on but don't start bike. Slowly open the throttle wide open then closed, open/closed a total of three times)

Bad coils could be an issue, but I'd assume it would be unlikely that several would go bad. I think the secondary coil is used during lower RPMS and then the primary takes over at higher?? You could swap/reseat them just in case.

Have a friend with a MotoScan or GS911?

Thanks

No friend with a GS911. I thought about buying one. I did do the TPS reset. Bike did idle fine after that. Rode it the next day and is stuttered while running high RPM's.
So I just took it home before it got worse.

Discussed with the Dealer and they said this is not a normal issue and will have to start testing all the different systems. This is above my knowledge level on this.
 
All four coils are in use at low rpm. As rpms rise, the timing on the lower coils shifts nearly 180º, and they don't contribute much to combustion. A loose coil wire on a primary coil produced intermittent hesitation and stumbling above ~3500 rpm on my RT, especially under acceleration. It ran normally at lower rpm or under light load. One way to check would be to disconnect a suspect coil, if the the bike runs worse that coil was good, if there is no change you found the problem.

I have not suggested coil trouble because apparently the problem has occurred while starting from a stop and required high rpm to get moving, which is quite different than the trouble I experienced.

Thanks
The first it happened was at high RPMs and when I parked it it was also doing it at high RPM's. I may check the coils before it go into the dealer, but I think I will take it there because I do not want to have this happen while I am out away from the house.
 
On my 2010 RT I had a intermittent misfire/stumble. I would be riding down the expressway on cruise, at a steady speed or accelerating and there would just be a brief stumble or feeling of a brief misfire. It was VERY intermittent and I saw no errors when I checked for codes with my GS-911. I tried injector cleaner and had synced the throttle body. Had about 60K. I replaced all the coils and spark plugs at the same time and it resolved the problem. I had done research on this and this seemed to be one of the causes of this and I finally decided to try it and that was the fix for me.

This is a source of BMW stick coils that would be an alternative to a BMW dealer:

https://www.euromotoelectrics.com/category-s/1754.htm

Did you get the coils from the dealer or from the source you sent? If you got them from the source, were there any issues? The savings is a couple hundred dollars.

I did test two coils last night and one is weak. I am thinking that I should just replace all 4 to be safe.

Thanks
 
The issues continue but are now different.

Well, I parked the bike at the end of April and had an appointment in early June at the dealer. Dealer let me know that the recall pump was not in but to go on and drop the bike off due to the fact they had aver a 3 month backlog of work. Dropped the bike off in June, and at the end of July the fuel pump came in. The pump was changed and I got the bike after the 1st week in August. dealer put about 70 miles on the bike and said it was good to go. First ride when I got home the bike stumbled. I rode the bike some, no issues. I have put only about 400 miles on the bike since then with no issues. I have been riding my new Moto Guzzi V850tt. Yesterday I took the BMW out and had a new problem. The bike felt like it was running out of gas. The tank was low so I filled up and headed home. Anytime I decelerated, it was like the bike was out of gas. It wanted to die. A couple of times I pulled in the clutch and the engine cut off. I headed home running rpms 5-7k. When I rolled off the throttle, the engine was like it was out of gas. Got home and the engine died at the bottom of the driveway. Bike would not start. After two tries I left the bike and went to the garage to look for my jump box since it seamed like the battery was low. Could not find it, went back to the bike, bike would not turn over first try, second try it turned over and started. Pulled into the garage. about an hour later put the battery on the battery tender and within 30 minutes it was showing a full charge.

I have put new plugs, 4 new coils, new fuel pump and there is some issue. I don't think the dealer did much other than the fuel pump. Same dealer says they can look at the bike the week before Christmas. I don't think I will take it back to them unless it is to see what they will buy the bike from me for. At this point I have no faith in my BMW that has 52000 miles. I know these bikes can easily run 100 K miles. I am super frustrated in what I consider to be the best road bike that I have ever owned.
 
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