Now I'm going to take mine apart just to make sure I have all those bits and pieces. I'm guessing that once you get a bit of debris blocking a passage the only solution is to tear it down and clean it out?
-Kyle On Fri, Mar 13, 2009 at 12:19 AM, Dennis Hammerl <[email protected]> wrote: > I haven’t been responding to any of this chatter about chatter because if > you can’t tell the difference between a cam chain rattle and a valve tap, > maybe riding the bus is more in order. I believe the noise described is a > valve clearance tap. Cam chain noise is a rattle and is most pronounced when > a motor is near idle. Raising the engine speed a few hundred RPM and letting > it settle back to idle should reveal a loose cam chain. A valve tensioner > (they do not have hydraulic lifters) operates on oil pressure and ensures > that the valves run at a zero clearance. The noise that a collapsed unit > makes does not go away with higher RPM’s ,. They just get more obnoxious. > They do become suddenly quiet at times. Why ? It’s because whatever was > keeping it from getting a supply of oil has become unstuck. Gee… Stick > around, it’ll be back. > > I will not describe the construction or function of this device since > readers don’t need or care to know. Failure (collapse) is caused by lack of > oil pressure. Lack of oil pressure is caused by too low an oil level or a > particle of dirt that reaches it’s tiny orifice, starving it. What about > this sudden increase of comment makes this all the more interesting to me is > that it references the CB650sc in deference to any of the others. (Nobody > is mentioning the CB700/750sc or later model 750’s) > > I will assume the role of Sherlock Holmes here and point out a difference > between all these bikes. In spite of the belief that they are related in > construction, they most certainly are not. Without going into the > differences (and there are many) the one that would account for this > phenomenon is the oil filter. All the others use a spin-on. Really hard to > mess that up. As I have serviced more of these than all the members of this > site own, I can relate a common flaw seen in many that passed through our > doors. An overwhelming number of these were found to be missing the spring > seat washer and / or the spacer in the filter housing. Add to that a number > that were assembled incorrectly. Now the 650sc is VERY critical of it’s oil > and it can’t be changed too often (this applies to all of this family) A > filter that doesn’t filter can’t be good. Low-grade filters don’t help any. > > Usually some well-meaning individual discards the old filter without > examining it. The spring seat washer clings to the old filter and out it > goes. Since you never saw it, you don’t know it’s gone. The spring is there > to hold the filter against the engine block. The spring seat washer prevents > the spring from creeping into the filter and allowing it to move away from > the engine block. Once it’s no longer held tightly, it ceases to filter. > Enter the dirt. It will pass through and come to rest somewhere. The > hydraulic tensioners only operate with oil pressure, they do not have a path > for it to return to the sump. Once dirt settles there… tap, tap. > > The finest grade of Llama arm-pit oil goes to waste if the filter assembly > is incorrect. > > A note to one respondent who seems to have nothing good to say about these > bikes; change brands… soon. You’ll sleep better. > > Anybody who wants to submit MP3 files of his/her motor noises is welcome. > > > > > --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Nighthawk Motorcycle Lovers!" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/nighthawk_lovers?hl=en -~----------~----~----~----~------~----~------~--~---
