09-05-2024, 11:22 PM
(09-05-2024, 04:43 PM)Wisedrum_imp Wrote:(09-04-2024, 12:56 AM)The ferret_imp Wrote:(09-02-2024, 02:08 PM)Dave_imp Wrote: 1) we have guys with close to 150,000 miles on their CB's with no major work. My personal bike is at 76K miles and the valves have never needed adjusting. Spec is every 16K I believe. Oil and filter every 4,000.
Hi Ferret, I am impressed that your bike reached 76K miles and never needed a valve adjustment. I am curious as to how you achieved this; my guess is you keep your engine RPMs low. I am convinced that valve wear is directly related to engine RPM - the higher the RPM, the greater the valve wear. I remember a post you made a long time ago where your gas mileage was pretty incredible also. Can you please share with us some details about how you ride? What is the typical RPM you ride? Is there a maximum RPM that you don't exceed? What RPM do you typically shift?
Also, can you please share at what intervals your valves were checked?
Thank you.
Dave, I ride a lot like Wisedrum. Typically in the 2500-3500 rpm range, normally shift about 3200 rpms, and although I haven't checked it lately I average about 57 mpg if memory serves me.
Valve cover has never been off. I go by symptoms as advised by my tech with 30 years experience working in motorcycle shops...it starts easily, runs great, gets good gas mileage, no weird noises. I also ride my NC 750 like that and I did have the valves inspected at 40,000 even though there were no strange symptoms, and not surprisingly all were in spec. I also had the valves on my ST 1300 inspected at 50,000 again with no bad symptoms, and again all were in spec. I also believe low rpms keep valves in spec but now it's the nature of how I ride anyway, and have for the last oh...25 years or so. For the first 30 years or so I rode a little let's say "wilder" racing here and there, seeing what every bike would do...but now I just cruise. Been there, done that so to speak .......
I believe engines are a lot like hearts...they only get so many beats/revolutions
The Chinese have a saying and I'll paraphrase: an elephant and a mouse get the same number of heartbeats in their lifetime. The mouse uses his up very quickly and doesn't live very long, the elephant uses his up very slowly, and lives a long time.
YMMV
Ferret, I like your analogy. If it's true or not, doesn't matter to me. Comparing animals with machines will probably fail, but I know, what you want say with your picture.
I prefer riding and driving my motorcycles and car within a commod rev range or with lows revs, if the engines will allow this way of riding. Only the Bullet doesn't really like too low revs as an old constructed one cylinder So why? I believe that all spare parts and the whole vehicle will last much longer, which matters a lot to me. It saves money also for fuel and I intend to keep them for as long as they will work without what we call in German a GAU. That means, without them having a very bad disease like a heart attack that will keep the engine or other very important and expensive but life necesassary parts from running and working. If this happens it will or may be the time to say goodbye to them.
Of course, you can rev the CB up high to the redline and I do it from time to time in a choosen gear 1, 2 or 3 to remind me of how strong and fast the Honda can accelerate and pull. 3,9sec from 0-100km/h. Fast like a
sport bike. This will certainly do the CB no harm. But mostly I don't like be sitting on a cannon ball and been shot away like mad. Definitely not my riding style.
I like this quote too, but then I kinda don't.
Me as a human, if I don't exercise and get my heartrate up daily (Lifting, running or manual labor - most days all 3) I feel my body start to slow down and my energy will crash hard. (I'm still a young buck at 25). And I know plenty of older folks who should've thrown in the towel years ago, but they keep going because they stay active. And I've seen the opposite true with a guy retiring so he can watch TV every day, then pass away shortly after retirement.
Obviously, an engine isn't a living thing in the same sense we are alive. But I think its good to give them some wide-open pulls now and again. I've dyno'd plenty of performance engines at my previous job, and setting rings is long hard low pulls, you make the engine work hard right from the get-go. I feel the same for letting it rev up to the redline now and again, maybe it doesn't clean valves or other internals as much as I'd like to think, since I have no data to back it up besides other old mechanics saying it's good to do so who knows?