The "weight" of the steering is dependent on several factors:
1)The size of the steering wheel
the length of the drag link on the steering column
2)The ackermann angle
3)the Caster angle
4) mechanical trail
5) pneumatic trail
6)Toe in/out
7)tyre pressure
For each factor there is a performance implication. You need to be sure that the speed the driver gains from 'light steering' is more than the performance lost by adjusting the setting from the optimal. Mind you, if the setting isn't optimal to start with, you may improve teh performance by moving closer to an optimal setting.
The size of the steering wheel and the drag link on the column are simply levers giving mechanical advantage. Obviously increasing the size of the steering wheel will give a greater leverage, but the rim of the steering wheel will have to move further....
The Ackermann angle will reduce load the closer you bring it to the rear axle. The setting is away from the rear axle to take account of the way race tyres perform.
Caster angle controls the degree of jacking and hence the degree of rear wheel lift and turning in of the Kart, less caster angle will mean turning the wheel is easier but may mean the kart understeers or over steers.
Mechanical trail is the distance between where the kingpin points at the ground and the centreline of the axle. Short mechanical trail means the steering is affected by every bump, long mechanical trail means the steering is more stable but needs greater effort to displace it.
Pneumatic trail is the distance behind the centre line of the axle and the effective turning point of the contact patch.
Toe in / Toe out affects the tendency of the steering to self centre or to need to be corrected back to track
Tyre pressure affects the size of the contact patch (and Pneumatic trail) and hence steering loads and performance.
You can alter all of these in a 'normal' kart. In a TKM altering the caster / camber and the associated physical effects is more difficult as you have to get round the "fixed" caster and camber rules, for example by getting the stub axles manufactured with offsets (which might not be strictly legal) instead of simply adjusting the king pin settings.
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TKM Viper Steering. by 'EvoRacer' (29 Jun 2014 @ 18:02)
