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CB500/550 / Re: Plugs fouling at idle
« Last post by McCabe-Thiele (Ted) on Today at 04:03:57 PM »My understanding of spark plug technology is they are designed to be self cleaning at higher revs/temperatures - obviously there is a limit to this function so if the mixture is overly rich right through the range they will soot up.
I suspect throttle blipping was something we used to do to keep the plugs from sooting up at idle to make a clean getaway.
My experience primarily with cars using carbs is that a vehicle used for mostly short journey work fitted with the manufacturers standard plugs would foul up badly needing a good run to clear the carbon deposits.
I particularly remember a disabled customer who ran an Automatic Opel Commodore 2.5 GS (1974) from his home to work a distace of less than a mile. On collecting his Opel from Ashbourne it would not exceeed 45-50 mph flat out. During the course of the journey to our service department in Burton the top speed would slowly improve until it would reach 60-65 mph. After a service the car would drive like it should for a 2.5 litre straight six.
Fitting a different plug type to cope with the short journey use mostly on auto choke was not an option as the customer would drive to Scotland a few times a year where he had family. In reality he woid have been better driving a car with a much smaller engine.
I suspect throttle blipping was something we used to do to keep the plugs from sooting up at idle to make a clean getaway.
My experience primarily with cars using carbs is that a vehicle used for mostly short journey work fitted with the manufacturers standard plugs would foul up badly needing a good run to clear the carbon deposits.
I particularly remember a disabled customer who ran an Automatic Opel Commodore 2.5 GS (1974) from his home to work a distace of less than a mile. On collecting his Opel from Ashbourne it would not exceeed 45-50 mph flat out. During the course of the journey to our service department in Burton the top speed would slowly improve until it would reach 60-65 mph. After a service the car would drive like it should for a 2.5 litre straight six.
Fitting a different plug type to cope with the short journey use mostly on auto choke was not an option as the customer would drive to Scotland a few times a year where he had family. In reality he woid have been better driving a car with a much smaller engine.