Runs rough; backfire; - 2001 BMW R 1200 C

it sounds like its starving for fuel, when it runs lean you will get backfires and if its running rough then it may be starving for fuel at idle. Try adjusting you mixture screw and see it the engine will smoot out. Your carb my be dirty and not allowing enough fuel through it.

U need to have the timing checked to be sure it is not the problem.

Is the check engine light on, and have you checked base fuel pressure with a gauge ?

spark plug wires need to be replace

I would adust the valves.

That is a car not a motorbike. Bikes only have 2 wheels. But you may want to set up the cam and ignition timing. it is only timing that will cause backfires.

For this types of problem,there are few help inks to troubleshoot the problem.Click the link below to go through the troubleshooting procedure to resolve the issues :----Idles rough and quits when gas pedal is pressed less? http://technoanswers.blogspot.in/2012/01/1999-ford-f-150-idles-rough-and-quits.html-----------van idles rough? http://howtobyme.blogspot.in/2012/01/2004-ford-freestar-van-idles-rough.html
--------------runs lean and idles rough? http://technoanswers.blogspot.in/2012/02/ford-runs-lean-and-idles-rough.html
-----------Car still runs Rough after tune up? http://howtobyme.blogspot.com/2011/12/car-still-runs-rough-after-tune-up.html
------------Idle flair is noticed on car? Rough idle? car will not idle? Erratic idle speed? http://technoanswers.blogspot.in/2012/02/idle-flair-is-noticed-on-car-rough-idle.html
----------High rpm in neutral? Inconsistant high RPM in neutral? http://technoanswers.blogspot.in/2012/02/high-rpm-in-neutral-inconsistant-high.html
------------Engine Backfires? http://technoanswers.blogspot.in/2012/02/jeep-backfires.html----------- Nissan stalls and bucks on Acceleration?

http://technoanswers.blogspot.in/2012/02/nissan-pathfinder-stalls-and-bucks-on.html

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Nissan Pathfinder Backfires? http://technoanswers.blogspot.in/2012/02/nissan-pathfinder-backfires.html
---------How to adjust rpm? http://schematicsdiagram.blogspot.com/2011/12/how-to-adjust-rpm-on-2009-dodge-charger.html
------------Engine cuts out at 3000 RPM? http://schematicsdiagram.blogspot.com/2011/12/engine-cuts-out-at-3000-rpm.html
----------This will help.Thanks.

Timing is off,problem with timing chain,also check fluids in ******,plus also if you have a distributer in your vehicle,if it is cracked,moisture getting in and ruining the points,-that is if your vehicle has a distributer! This will make a vehicle run rough as well.
You can have new plugs put in,but if your spark plug wires are cracked or worn,this will also creat misfire and backfiring.

common causes for back firing, low fuel pressure, or restricted injectors, breakdown of secondary ignition coil, internal ignition coil arching, or a dead spot in throttle position sensor.

check the mass air flow sensor in the air cleaner tube,it may have a white piece of fuzz on it from the filter and it changes the readings of how much air its getting.