Fouled Plug and Stumbling Question

[TTM3]

2011 R1200RT low speed tip over in an off camber, debris covered roundabout. Hard down on left side and broken ankle. Produced a comma shaped scrape on head guard as it went down quickly and pivoted on the head. Hit the kill switch (rear wheel was still rotating), stood it back up with help, gathered my senses and rode home - engine stumbling along the way (about 6 miles). Managed to get it up on center stand and left it for a few weeks (X-rays and a boot). Restarted, but the engine was running rough. Pulled the Tupperware, guard and plugs. No damage or pinching of ignition coils/wire. I was parked on cardboard and there was evidence of a light oil leak spread over a larger area directly under head, but no leaks now. Upper plug was black, but lower plug was coated in oil including a few drops from lower plug thread area. Cleaned and reinserted the plugs (fairly new less than 2K since change) - now running a little better, but still stumbling at lower revs. Left header and exhaust seems to be getting very hot and smoking a little - right side exhaust seems normal. Any thoughts?

 

 

[dirtrider]

5 hours ago, TTM3 said:

2011 R1200RT low speed tip over in an off camber, debris covered roundabout. Hard down on left side and broken ankle. Produced a comma shaped scrape on head guard as it went down quickly and pivoted on the head. Hit the kill switch (rear wheel was still rotating), stood it back up with help, gathered my senses and rode home - engine stumbling along the way (about 6 miles). Managed to get it up on center stand and left it for a few weeks (X-rays and a boot). Restarted, but the engine was running rough. Pulled the Tupperware, guard and plugs. No damage or pinching of ignition coils/wire. I was parked on cardboard and there was evidence of a light oil leak spread over a larger area directly under head, but no leaks now. Upper plug was black, but lower plug was coated in oil including a few drops from lower plug thread area. Cleaned and reinserted the plugs (fairly new less than 2K since change) - now running a little better, but still stumbling at lower revs. Left header and exhaust seems to be getting very hot and smoking a little - right side exhaust seems normal. Any thoughts?

 

Morning TTM3

 

Difficult to tell you anything conclusive as we don't know if any hidden damage was done. But assuming no physical damage to the valve cover seal area or cylinder head  then possibly just an oil related issue.

 

When they go over on their side like that then some oil usually gets by the piston & into the cylinder, but if there was any oil in the bottom of the air cleaner box, (there usually is a little due to the crankcase venting into the air cleaner box), especially if the engine was running when it went on it's side,  then a lot of that air box  oil also went into the low side combustion chamber through the intake tube & throttle body.

 

As you noted it had a fouled lower spark plug (normal after a tip over with running engine) but once the engine was started after the tip over then some of that oil probably also fouled the o2 sensor on that side. That can cause all kinds of poor running engine issues until the oil burns off. 

 

It very well might start running OK again after a good hard riding session. 

 

As for the oil on the ground?__ That is a puzzler if there are no obvious signs of an oil leak but it still could be air box oil related, or a slightly displaced valve cover gasket, or even some of that excess oil seeping out of an exhaust joint over the time the motorcycle was sitting.   

 

About all you can do here is clean it up as best possible then keep watching for oil leakage. 

[TTM3]

Thanks for the help Dirtrider. The left cylinder seems fine now after cleaning the plugs a few times, but when I was checking the airbox for oil, I discover a different issue on the RIGHT side ... the throttle cable is just dangling and holding one half of the round plastic disk that rotates the throttle plate right behind the Tension Spring.

 

 

 

 

[dirtrider]

18 minutes ago, TTM3 said:

Thanks for the help Dirtrider. The left cylinder seems fine now after cleaning the plugs a few times, but when I was checking the airbox for oil, I discover a different issue on the RIGHT side ... the throttle cable is just dangling and holding one half of the round plastic disk that rotates the throttle plate right behind the Tension Spring.

 

 

 

 

Evening TTM3

 

Those cracked/broken Throttle Body cams are an issue that can appear on any of the hexhead or camhed 1200 bikes.

 

Kind of expensive to have a shop repair it but much cheaper to do yourself if have the expertise. 

 

This link  will give you some reading on the failures & how to repair_____________   https://www.bmwsporttouring.com/search/?&q=throttle cam&page=1&quick=1&search_and_or=and&sortby=relevancy

 

 

[TTM3]

DirtRider - Thanks for all the help and reference posts. I've read and researched, gathered parts and supplies, and was hoping to start this weekend, but I had a few more questions:

 

1.) My 2011 RT has a 77/50 Bing throttle body, so Bing had me order the left and right throttle body pulleys. The kit also included some additional screws, port covers, body cap, etc. (NO shafts). So will this require drilling into the end of a solid shaft and tapping for the screw that holds the pulley levers? Or am I tapping an existing hole? I'm concerned that I would need machine shop help.

2.) I guess the alternative is to send the parts and both throttle bodies back to Bing for their installation service.

3.) If it has to be machined - could this be accomplished without pulling the shafts?

 

Bing did warn me: If you have 77/47 you can replace the complete shaft and pulley assembly which is a fairly easy job.  If you have 77/50 then you must use your original shafts and replace the pulleys, I have attached instructions for this.

 

 

[dirtrider]

11 hours ago, TTM3 said:

DirtRider - Thanks for all the help and reference posts. I've read and researched, gathered parts and supplies, and was hoping to start this weekend, but I had a few more questions:

 

1.) My 2011 RT has a 77/50 Bing throttle body, so Bing had me order the left and right throttle body pulleys. The kit also included some additional screws, port covers, body cap, etc. (NO shafts). So will this require drilling into the end of a solid shaft and tapping for the screw that holds the pulley levers? Or am I tapping an existing hole? I'm concerned that I would need machine shop help.

2.) I guess the alternative is to send the parts and both throttle bodies back to Bing for their installation service.

3.) If it has to be machined - could this be accomplished without pulling the shafts?

 

Bing did warn me: If you have 77/47 you can replace the complete shaft and pulley assembly which is a fairly easy job.  If you have 77/50 then you must use your original shafts and replace the pulleys, I have attached instructions for this.

 

 

 

Morning TTM3

 

I haven't done a 77/50 yet but is does appear to be same as the 77/47 as far a cam attachment goes. 

 

It will be a bit involved to install the new cams with the shaft still in the throttle body but probably can be done.

 

The first issue you will face is getting the old cam off the shaft without bending or damaging the shaft. You will need to grind the outer staking (shaft part that sticks out from the cam) flush with the cam surface. 

 

Then use a small bearing puller, or make up a cross bar with a center bolt & outer holes to bolt to the cam then act as a cam-puller, or find a way to cut or grind the cam away from the shaft. (it helps to remove the plastic parts of the cam  from the metal part before working on it).  

 

On the other hand (with the shaft & cam removed)  you can simply grind the outer staking flush, then drop the shaft/cam over a piece of pipe (or stack of nuts) then drive the shaft out of the cam with a drift & hammer. 

 

Some will  come right off the shaft with little effort & wiggling & others are quite a bit tighter.

 

Once you get the cam removed without bending or damaging the shaft then you need to carefully drill the end of the shaft then tap that hole  to have proper threads to fit the screws furnished with the cams. This hole needs to be straight and in the center of the shaft and deep enough for the furnished screw to thread all the way in.  

 

You can then use those tapped threads to help pull the new cam onto the shaft. Personally I would not use the supplied screw to pull the cam onto the shaft  but would buy longer screws (of proper thread size & pitch) & couple of nuts  washers.

 

Then screw one of the nuts all the way on the longer screw, then add a couple of proper sized washers, then add a larger washer, (larger than the cam hole size). Then screw that longer bolt into the shaft end in as far as it will go, THEN screw the nut down on the screw to smoothly pull the cam onto the shaft. LOT LESS chance of stripping the furnished screws or shaft threads that way as you have full thread engagement thought-out the entire cam pull-on process. 

 

 

[The Fabricator]

The OP stated the engine still ran with the bike on it's side.

Is there no tip over sensor which kills the ignition?

[dirtrider]

1 hour ago, The Fabricator said:

The OP stated the engine still ran with the bike on it's side.

Is there no tip over sensor which kills the ignition?

Afternoon Tom

 

No real dedicated tip-over sensor, but if they fall over on the right side and have about 1/2 or less fuel in the tank then the pump will run dry so they won't run long. 

 

They will usually pump enough oil into the air box through the breather when running on their side that they eventually quit running.  (well at least the lower cylinder quits running anyhow) 

[TTM3]

So I finally was able to complete the repairs with the help of a machine shop to drill and tap the throttle shafts ($40). Some lessons learned:

 

1.) Take lots of pictures during disassembly

2.) I was able to take everything apart without turning any adjustments - that includes the throttle cable - just a little metal tab releases the cable from the plastic holder/guard and it pulls right out (don't cut it!) 

3.) Removing those metal hose clamps was a real struggle especially as they were turned into the bike making access almost impossible

4.) Removed the clamp and throttle body from the head side first, then had to really bend it out from the airbox to get access to the clamp clips

5.) I really tore up the clamps using the tool pictured above - but found this smaller (multipurpose) Crescent brand 8" tongue and grooved pliers which were fantastic ($18.97 from Home Depot)

6.) Ordered new clamps (<$6 each) - two different sizes on each end of throttle body - reinstalled with clip nubs out!

7.) Use plenty of silicon spray to ease reinserting throttle body into hoses 

8.) Throttle body can be rotated a little while reinserting injectors, throttle cable, guard, etc.

9.) Was able to manual open throttle and get the throttle cable reinserted from underneath - again, no change in any settings which I paint marked

10.) Once everything verified, re-installed clamps

11.) Bike started and ran fine - now I can proactively replace left side

12.) In the future, I just need to reorder replacement cams from Bing as the the shafts are already drilled and tapped (plus at that time I may need to rebuild the bearings & body (the "clicking throttle body problem)

 

I really appreciate all the help Dirt Rider! A lot less expensive now and in the future compared to replacing whole throttle assemblies!

 

[bruce2000ltc]

Tom -- Thanks for the follow up...great write up and photos!

 

My '13RT is coming up on its 72000 mi service and I'm going to check the throttle cams then.  Hopefully they're ok but at some point I'll probably be faced with their replacement.  Thanks to you and "dirtrider" I'll be prepared and hopefully will find them cracked before failure.

[TTM3]

LEFT side Throttle Body plastic cam update:

1. I was lucky that both clamp nubs were facing out and I was able to easily release with no damage.  I still recommend buying spare clamps to help you figure out which nubs to pinch for release & replacement(s) if damaged.
2. Detached throttle valve switch & idle control valve cables and clip cable ties. Detach fuel injection valve.
3. Was able to easily rotate the throttle body assembly (silicon spray) for better access to backside throttle cable assembly.
4. Pulled plastic cover up along the cable and out of the way. Manually rotated plastic cam to release cable end (hemostats helped), then released small flat shinny tab to pull cable free of throttle body.
5. Throttle body easily came free from head side, then airbox side.
6. Bench inspection showed the plastic cam was cracking but still in place
7. Disassembled everything and rushed to machine shop to drill and tap while I waited. Nice CNC machine, drilled, tapped ... and then the tap broke off flush inside ... panic set in!
8. Luckily, I was able to get a new left side shaft from BING (the last one) and they don't make the right side anymore, so you may be scouring the network for used shafts if this happens to you - be careful.
9. The machine shop could have tack welded the new cam to shaft, but then future replacement is not possible.

I did realize that the larger spring around the shaft has a special fitted place or channel as it wraps around bottom fixed plastic (near lower screw). I’ll have to correct the right side. See pictures.

 

This was also an opportunity to access the chain tensioner to tighten (15 mm wrench) – easy access and a common issue with CAMheads!

 

Finally, as a CB (cheap bastard), the JB Weld and washer solution is cheap & effective, especially in an emergency, just make sure you clear the plastic guard. This cam replacement solution from BING is more expensive, but keeps things more "OEM" and replacing the plastic cam and rebuilding the throttle body in the future will be so much easier. Finally, taking the bike to BMW for two new throttle bodies is easy, but NOT CB-certified at $1200 to $1600 with parts and labor, but BMW only deals in complete throttle bodies.

 

Ride safe and I hope this helps!