Being roller bearing big ends do those require more frequent changes than bushings? I think I remember hearing that early bugatti's had roller bearing cranks that required 5k inspections/ repalcements?
All frictionless bearings have a stated life with a given speed and load. In theory, bushings can have an infinite life, if treated properly. But realistically, ball and roller bearings can last the life of the machine if the design was proper and they are also treated properly.
The roller bearings work well as long as the crank and or the engine cases or block does not distort under load, keep in mind that old Harleys are only around 50hp using that 5 piece crank shaft. The newest models, the shafts and the flywheels are one piece using a straight crank pin with a very heavy press fit instead of nuts, stronger engine cases handling over 100hp factory stock. The roller bearing design requires a closed end rod meaning multicylinder crankshafts would have to be built up and for the period of old race cars likely held together with nuts for the removable crank pins. There is a lot that can go wrong and the shafts and crank pins of the period were carburized mild steels or case hardened. Any pinching of the bearings causes the case hardening to flake off the crank pins or other shafts resulting in what was known as "mystery bearing failure" or chewed up mess. Todays through hardening alloy steels makes roller bearing rods more reliable, more to come on that subject, thanks!
Great to see you back, you make very interesting videos!
Thank you very much!
Welcome back Don! Looking forward to more of your great content. Where in the world did you get all those antique machinery brochures?
Great to see you back!
I got locked out, but found another way in, thanks
Glad to see you back , started to worry about ya, nice hair cut
All good, thanks!
Glad your back...
Thanks, I have the technical problem pretty much fixed
After a comment you made on your last video, I was concerned we’d lost you, Don. Glad that’s not the case - I love your content!
Almost lost, I was able to regain access through an old computer. Thanks for tuning in!
good to see you back Don
Thanks for tuning in
Hip hip horay.......... good to see you back live!!!!
Glad to be back, thanks
Welcome back!
Thanks for watching!
Being roller bearing big ends do those require more frequent changes than bushings? I think I remember hearing that early bugatti's had roller bearing cranks that required 5k inspections/ repalcements?
All frictionless bearings have a stated life with a given speed and load. In theory, bushings can have an infinite life, if treated properly. But realistically, ball and roller bearings can last the life of the machine if the design was proper and they are also treated properly.
The roller bearings work well as long as the crank and or the engine cases or block does not distort under load, keep in mind that old Harleys are only around 50hp using that 5 piece crank shaft. The newest models, the shafts and the flywheels are one piece using a straight crank pin with a very heavy press fit instead of nuts, stronger engine cases handling over 100hp factory stock.
The roller bearing design requires a closed end rod meaning multicylinder crankshafts would have to be built up and for the period of old race cars likely held together with nuts for the removable crank pins. There is a lot that can go wrong and the shafts and crank pins of the period were carburized mild steels or case hardened. Any pinching of the bearings causes the case hardening to flake off the crank pins or other shafts resulting in what was known as "mystery bearing failure" or chewed up mess. Todays through hardening alloy steels makes roller bearing rods more reliable, more to come on that subject, thanks!
Good morning Don...glad to see you back on track..Paul ❤
Me too!
Good to see you Back Thanks for the video
Hi Frank, found a way back into this channel.
Great to see you Don!
Hi, thanks!
Welcome back Don.👍
Thanks for that!
Great to see you're OK! I worried when a month went by with no posts from you.
Computer/access problems, good to be back, thanks.
Nice to see you back keep the videos coming
I will work on that, thanks
welcome back Don.
Hello. thanks
Howdy Don, hope you're keeping well buddy
Hi, feeling good
Are you going to do both channels, or give one up?
I better keep a reserve or two,
What’s the podcast channel going to be called DeeDee
Don Dyar Machining, thanks!
Welcome back Don! Looking forward to more of your great content. Where in the world did you get all those antique machinery brochures?
Thos are just images, thanks