Originally Posted by
vafactor
Question 1 - why have all of the latest 1/12th scale cars gone to the fixed kingpin non-reactive style front ends?
Question 2 - Can one of the suspension gurus out there please explain the effects of using reactive caster? I’m no expert, but it does seem to me like more caster would help the car be more stable while going straight and less caster under suspension loading would help to add steering in the corners. Is my logic correct? or am I missing something? If so please help me to understand.
Reactive caster faded from 1/12 scale pan cars because modern racing moved heavily toward high-grip carpet (CRC Black Carpet) tracks and ultra-precise static suspension systems. Racers found that dynamic, changing caster hindered predictability.
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- Simpler Setup: Modern cars use fixed, static caster by easily adjusting shims on the upper arms. This provides consistent handling throughout an entire corner.
- High-Grip Surfaces: Reactive caster was originally popularized to make cars easier to drive in a straight line while still aggressive in corners. Modern 1/12 scale racing relies on high-traction, and high grip tires where straight-line stability is less of an issue, and mid-corner steering is paramount.
- Tweak-Free Performance: Link-style front ends and newer independent designs provide perfectly linear, bind-free steering without the suspension slop associated with older reactive caster blocks