Talk:Main bearing

Uncited information
The following info was removed from the page because it lacked citation. Information on the Ford V8 and Chevrolet 6-cylinder was incorporated from other wikipedia articles. I'm putting the removed content here in case someone wants to find citations and add this to the page.


 * All [MOST]single- and V-twin-cylinder engines have at least two main bearings, one at each end.
 * Parallel (inline) twin engines as used in motorcycles may have two, three, or four main bearings. Broadly speaking, older British twins had two main bearings. Japanese twins typically have four.
 * Most modern four-cylinder petrol [engines have five main bearings, though three were once often used.]and [S]some inline six engines have [used] three main bearings, [such as some old Hudson engines,]the third in the middle. However, [all current design] four-cylinder inline diesel engines usually have five main bearings, due to the heavier loads imposed on the crankshaft.
 * Almost all current production inline six-cylinder engines have seven main bearings. Older inline sixes often had either three or four main bearings.
 * All modern V8 engines have five main bearings, with one crank pin between each pair of adjacent main bearings. Old designs, such as the Ford flathead V-8, produced from 1932 through 1953, often had three mains.
 * Most straight-5 engines have six main bearings, to help counter the essential imbalance of this design.

128.61.94.57 (talk) 05:29, 28 February 2013(UTC)

More uncited
"The number of bearings and crank pins can also have an effect on engine balance; a more stable crankshaft will better avoid unbalance from flexing, but increasing the crankshaft length or girth to accommodate an additional bearing increases the rotational inertia of the crankshaft, which can have the opposite effect."

If the crank loses stability it's over for the engine. Maybe there is a better way to word this. Crank length doesn't effect rotational mass, it's the weight. Torsional flex yes, but all the 4 and 6 bolt engines never needed to accomodate a larger crank. Even when 2 bolts were an option cranks stay the same.Dana60Cummins (talk) 16:48, 25 November 2020 (UTC)

Diagram request
Six-bolt main bearings - can we have a diagram of the bolt layout, please, it's easier to interpret than text — Preceding unsigned comment added by Alanthehat (talk • contribs) 10:54, 29 January 2022 (UTC)