QuestionMark..I've got a 99 Vulcan 800 with only 18000 miles. Within the last roughly four months,I've noticed a loud 'ticking',think volkswagen beetle,coming from the engine. It doesn't do it at idle,only on throttle. If I'm moving,it stops as soon as I let off throttle. It doesn't sound like valve knock,at least what I'm familiar with. I've heard knock on this motor,when I pick too high a gear. Everyone tells me this is normal for a Kaw motor,but I don't like new sounds,especially when I can hear them over the wind. I do oil changes,probably more than I need to. The first mod I did,and the only one BEFORE this sound started,was to drill holes in the rear baffles.
Later mods include a foam filter and jet kit from Dynojet. I just did a valve adjust a month ago. With the exception of one,they were all one thickness tighter than specs.
AnswerHi Ron,
Ticking and tapping sounds are common with loose or excessive valve clearances. The sounds may disipate or become quiet as the engine reaches operating temperatures and metals expand.
Similar sounds may indicate bent valves. With bent valves, the ticking sound is usually: 1) more pronounced, 2) lounder than the sound of excessive clearance valves, 3) the frequency of sounds is proportinate with rpm's, and 4) the sound dosen't go away as engine warms.
I would check cylinder compression with engine at operating temps. This will determine if there is any compromises of the combustion chambers sealing properties. If compression is within service limits, go through the work of checking valve clearances. If compression is not within specs, perform a leak-down test to determine exact source of defective parts. Be sure engine is at room temperature when checking valves. Allow engine to cool overnight. With screw adjuster type rocker arms, we insert a feeler gaguge under each of the two valves simutaneously. This may not be necessary with the Kaw's valve shim set up.
Respectfully,
Mark Shively
