Found this on t'other site........
Good afternoon, Ladies And Genteel men.
I now present to you the most wonderful cure for ailing (indeed, all) BMW F650 motorcycles:
1) Pull off your spark plug cap or caps if you have several.
2) Rip the b...... stupid metal caps orfff the flipping plug caps and thow them as far as you possibly can using a Very Big Large Scrap Metal Throwing Gun, into Outer Space if possible, so that no one else will be eternally punished by them.
3) Put the rubber plug caps back on the plugs.
4) Don your jacket and helmet, place key in ignition, start engine and Hold On For Dear Life. You are now riding a completely different bike. The speedo needle shoots up the gauge like never before. It goes. The bike stops without the engine following suit. You can at long last keep up with a dust cart. And even overtake it if conditions are safe to do so (but be careful to look in your mirrors first and remember that objects may be closer than they appear). (( what on earth does that mean? so what if they are closer than they appear? I guess it is a hint that if the cops are chasing you, you need to go faster))
Oh, what a wonderful change has come into my life. The thought has even occurred to me to go to a BMW dealer, and shock, horror, heaven forbid, buy a new one!!!!!!!!!!!!!!!!!!!!!!!!!!!!! All I have to do after leaving the dealer is stop around the first corner and relieve the bike of this awful affliction.
I WOULD SERIOUSLY RECOMMEND THIS SIMPLE MOD TO EVERYONE THAT HAS STEEL PLUG TOPS.
Here is a technical explanation if any of you are interested. I'll steer clear of Ohm's law cos its not necessary, though it is the essence of the problem.
You have about 20,000 volts going down the HT lead to the spark plug. At the spark plug gap it has a big task ahead of it to jump the gap, particularly when the fuel/air mix is compressed inside the cylinder. If it can, the electricity would rather go somewhere else. It is all the time looking for the shortest path to the chassis. That is, the path of least resistance. The plug gap may not be the path of lest resistance, the steel plug top might be the path of least resistance, as it is connected to the plug body which in turn is connected to the engine, etc etc. Firing the cylinder mixture is entirely dependent on the insulation of the black HT lead remaining higher than the resistance of the plug gap. If the resistance from the wire inside the black HT lead to the outside of the balck HT lead gets less than that of the plug gap, then the electrical pulse will run through the HT lead insulation to the steel plug cap and jump straight to the chassis. This leaves a reduced voltage available for the spark. When the insulation gives up completley you have 0 volts for the spark, which is not healthy.
I am thrashing myself severely with birch branches for not thinking of this before and not doing it to my bike as soon as Priesty found that it made a huge difference to his bike.
Good afternoon, Ladies And Genteel men.
I now present to you the most wonderful cure for ailing (indeed, all) BMW F650 motorcycles:
1) Pull off your spark plug cap or caps if you have several.
2) Rip the b...... stupid metal caps orfff the flipping plug caps and thow them as far as you possibly can using a Very Big Large Scrap Metal Throwing Gun, into Outer Space if possible, so that no one else will be eternally punished by them.
3) Put the rubber plug caps back on the plugs.
4) Don your jacket and helmet, place key in ignition, start engine and Hold On For Dear Life. You are now riding a completely different bike. The speedo needle shoots up the gauge like never before. It goes. The bike stops without the engine following suit. You can at long last keep up with a dust cart. And even overtake it if conditions are safe to do so (but be careful to look in your mirrors first and remember that objects may be closer than they appear). (( what on earth does that mean? so what if they are closer than they appear? I guess it is a hint that if the cops are chasing you, you need to go faster))
Oh, what a wonderful change has come into my life. The thought has even occurred to me to go to a BMW dealer, and shock, horror, heaven forbid, buy a new one!!!!!!!!!!!!!!!!!!!!!!!!!!!!! All I have to do after leaving the dealer is stop around the first corner and relieve the bike of this awful affliction.
I WOULD SERIOUSLY RECOMMEND THIS SIMPLE MOD TO EVERYONE THAT HAS STEEL PLUG TOPS.
Here is a technical explanation if any of you are interested. I'll steer clear of Ohm's law cos its not necessary, though it is the essence of the problem.
You have about 20,000 volts going down the HT lead to the spark plug. At the spark plug gap it has a big task ahead of it to jump the gap, particularly when the fuel/air mix is compressed inside the cylinder. If it can, the electricity would rather go somewhere else. It is all the time looking for the shortest path to the chassis. That is, the path of least resistance. The plug gap may not be the path of lest resistance, the steel plug top might be the path of least resistance, as it is connected to the plug body which in turn is connected to the engine, etc etc. Firing the cylinder mixture is entirely dependent on the insulation of the black HT lead remaining higher than the resistance of the plug gap. If the resistance from the wire inside the black HT lead to the outside of the balck HT lead gets less than that of the plug gap, then the electrical pulse will run through the HT lead insulation to the steel plug cap and jump straight to the chassis. This leaves a reduced voltage available for the spark. When the insulation gives up completley you have 0 volts for the spark, which is not healthy.
I am thrashing myself severely with birch branches for not thinking of this before and not doing it to my bike as soon as Priesty found that it made a huge difference to his bike.
