Camber and Caster eccentric pills


(Christopher Ramnauth) #1

Hey guys so this post is going to surround the eccentric pills that adjust the camber/caster on the front end of karts. I’ll be specifically referring to the newer design that’s on the like of birel, compkart and I think tonykart uses the same setup, basically a dial with holes that you rotate and then lock in place with a little screw.

Right, so the C of all chassis are built with a certain amount of fixed camber and caster, the eccentrics then let you add to or remove from that initial amount.

What I want to know, is there a general universally accepted position on the top and bottom eccentric that is referred to as neutral or base setting across all manufacturers that use the system that I’ve described?

For instance if we reference a 4 point compass N,S,E,W and apply it to the eccentric. Would setting both top and bottom to either both on N OR both on S etc etc really be the same exact setting ? And if so, is this what chassis manufacturers call the base or neutral? Would this be the same as using the static built on camber and caster of the C of the chassis?

Hope I didn’t confuse you guys, looking forward to the discussion


(John Leah) #2

Forgetting the pill manufacturers markings for the moment, and looking at the pills in the metal.

Eccentric pills have the king pin hole out of centre to the 22mm? location diameter.

This gives rise to a variation in the wall thickness of the metal between the king pin bore and the 22 mm location diameter.

The point of max. wall thickness can be marked on each pill to be visible when fitted and used as YOUR datum for positioning.

If the pills, top and bottom are fitted with this datum pointing in the same direction, be this forwards, backwards , sideways or in between, then caster and camber will remain at the neutral setting governed by the positioning of the ‘C’ at manufacture. There will be a marginal change in wheelbase, track or both which can be ignored?

You then need to determine how the pill manufacturer has marked the pills. ie.what symbol on the pills corresponds to YOUR marked datum as above. You are then in a position to use the manufacturers markings to adjust caster and camber to your requirements.


(Christopher Ramnauth) #3

Ok so I think you answered one of my questions about if both pills are pointing the same direction, then effectively you are using the static camber/caster built into the C of the chassis.


(John Leah) #4

Yes to all three questions assuming the pill manufacturer has marked the pills properly and in a ‘sensible’ way that we understand. Not sure if this is always the case?


(Christopher Ramnauth) #5

Thanks for your input John. Say the datum is pointing inward toward the centre of the kart top and bottom. If you move the one on top only say clockwise one notch and leave the bottom untouched, what would this do? Change camber? Caster? Or both?

I guess what I’m getting at is can you change camber and keep caster constant and vice versa?


(John Leah) #6

No. The shortcoming of these systems is just that ie. you can’t alter caster without altering camber.
The Sniper type systems and others allow independent adjustment.
Bear in mind that camber changes massively when you put on steering lock .