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Old Aug 16, 2012, 07:36 AM
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Earl, there is a slightly different reason for your Harley doing this, I'm sure yours is carbed. When the rear cylinder is filling, the air/fuel mixture has to make a sharp left turn to enter the rear intak valve. Then as the rear intake valve closes and the front intake valve opens the fuel/air mix must come ot an abrupt stop and turn right to enter the front intake valve. This is the main cause of the famous Harley shake at idle. The early fuel injected ones did not do this, so after early test riders complained, the skake is programmed in to the ECM. The fuel injected bikes don't have that shake because the injector only injects fuel while the intake valve is open.
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