With much lighter weight you can (and they DO) use bushings instead of wheel/axle bearings. This goes even deeper into the drive system... The transmissions can be bushed.
Engines do not have to be built to deal with constant torque loads... Steering is built much lighter. Everything goes down Cost, quality life expectancy, And you end up with a under $2000 rider or a under $3000 ZTR.
In MOST cases this will not be a problem for the average residential user. BUT when someone gets the idea that they can get one of these light weights to do even mild commercial use, or large acreage... They are only kidding themselves.
AND these are the users that give the various mower manufacturers a bad name. They are buying the wrong tool for the job they have in mind.
Manufacturers will make the lighter models 'LOOK' like the commercial lines, from a distance.
You will find the same thing in tool makers... I'm sure you have seen hammers that sell for a dollar, at a glance you will identify it's a hammer... but don't compare it to a $30 framers hammer.
The older riders were down scaled tractors... and they have lug nuts that bolt the drive wheels to hubs on the axles... the front wheels are on wheel bearings, and the steering linkage has ball joint or hymen linkage...
Used within the design limits the light weight equipment will do the job for some folks...
BUT if you want it to last the best part of your lifetime, buy an actual commercial grade machine. Then you will be 'occasionally' repairing rather than replacing... :smile:KennyV
PS.. I'm an old geezer ... I like OLD machines, have several, just because they are fun and easy to look at....
