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838:
20:
44:
28:
142:(reducing its tendency to wander). Excessive caster angle will make the steering heavier and less responsive, although in racing large caster angles are used for improving camber gain in cornering. Caster angles over 7 degrees with radial tires are common. Power steering is usually necessary to overcome the jacking effect from the high caster angle.
102:
Caster causes a wheel to align with the direction of travel, and can be accomplished either by caster displacement or caster angle. Caster displacement moves the steering axis ahead of the axis of wheel rotation, as with the front wheels of a shopping cart. Caster angle moves the steering axis from
154:
The steering axis (the red dotted line in the diagram above) does not have to pass through the center of the wheel, so the caster can be set independently of the trail, which is the distance between where the steering axis intersects the ground, in side view, and the point directly below the axle.
121:
In it he stated it was intended "To ensure stability of direction by means of a special arrangement of fore-carriage, that is to say, to re-establish automatically the parallelism of the two axles of the vehicle when there is no tendency to keep them in any other direction, or after a temporary
197:, caster is adjusted to achieve a self-centering action in the steering, which affects the vehicle's straight-line stability. Improper caster settings will require the driver to move the steering wheel both into and out of each turn, making it difficult to maintain a straight line.
169:
are an extreme case – the system is undamped but stable, as the wheel oscillates around the "correct" path. The construction has relatively high trail, but no caster, which allows changing of direction with minimal force.
122:
effort has caused them to diverge from said parallelism. The axle of the fore-carriage is situated a suitable distance behind the projection of the axis of the pivot-pin in order to ensure the stability of direction above referred to."
145:
Some front-end alignment calls for different right-side and left-side caster. This is called cross caster, and the difference is called the spread. Cross camber may also be specified, but not usually both.
130:
The steering axis is angled such that a line drawn through it intersects the road surface slightly ahead of the center of the contact patch of the tire on the pavement by a distance called
185:
and varies with speed, load, steer angle, surface, tire type, tire pressure and time. A good starting point for this is 30 mm behind the center of the contact patch.
295: : the slight usually backward tilt from vertical of the axis of the steering mechanism of an automobile for giving directional stability to the front wheels
106:
In automobile racing, the caster angle may be adjusted to optimize handling characteristics for a particular venue. This is all connected to the front wheels.
158:
Caster angle and trail both influence the steering, albeit in different ways: caster tends to add damping, while trail adds "feel" and returnability.
424:
350:
872:
212:
64:
417:
373:
719:
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131:
134:. The purpose of this is to provide a degree of self-centering for the steering—the wheel casters around in order to
410:
235:
206:
226:
Some bicycle constructors refer to the angle subtended by the mechanical trail at the wheel center as caster.
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proposed placing the front axle of a car at a positive caster angle in his UK patent of 1896, entitled
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castor angle, the angle at which the steering-head of the front wheels of a motor vehicle is set
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16:
The angle between the vertical axis and the steering axis of a steered wheel, in side view
8:
714:
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837:
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138:
behind the axis of steering. This makes a vehicle easier to control and improves its
23:θ is the caster angle, the red line is the pivot line, and the grey area is the tire.
211:
In the context of bicycles and motorcycles, caster is more commonly referred to as "
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or a vessel, as seen from the side of the vehicle. The steering axis in a car with
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the caster angle is formed by the line between upper and lower ball joint
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to the center of the lower ball joint, or through the center of the
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219:. The terms caster or castor angle are still predominantly used in
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181:, but at a point behind the center. This distance is called the
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is an imaginary line that runs through the center of the upper
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43:
27:
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Automotive
Service: Inspection, Maintenance, Repair
215:", "rake angle" or "rake and trail", especially in
177:forces at the tire do not act at the center of the
307:
864:
119:Improvements in mechanically propelled vehicles.
314:(2nd ed.). Oxford University Press. 1989.
418:
51:with a raked fork at an extreme caster angle
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411:
361:
193:When the front suspension of a vehicle is
125:
42:
26:
18:
200:
865:
188:
406:
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368:. Cengage Learning. pp. 1273–.
149:
67:from the vertical axis of a steered
63:is the angular displacement of the
13:
720:Electronic brakeforce distribution
14:
884:
873:Automotive steering technologies
847:
846:
836:
99:for vehicles having a kingpin.
236:Bicycle and motorcycle dynamics
207:Bicycle and motorcycle geometry
382:
344:
321:
300:
273:
31:Front suspension of a race car
1:
330:Learn Camber, Caster, and Toe
266:
725:Electronic stability control
390:"Arctan(Trail/Wheel Radius)"
281:"Merriam Webster Dictionary"
7:
612:Ackermann steering geometry
362:Tim Gilles (24 July 2012).
229:
10:
889:
675:Active rollover protection
204:
109:
89:dual ball joint suspension
832:
768:
655:
602:
454:
441:
310:Oxford English Dictionary
670:Anti-lock braking system
464:Anti-roll bar (sway bar)
700:Combined braking system
524:Independent suspension
52:
40:
24:
544:Multi-link suspension
140:directional stability
126:Positive caster angle
46:
30:
22:
201:Two-wheeled vehicles
715:Electric park brake
333:, COME AND DRIVE IT
189:Front-end alignment
755:Regenerative brake
53:
41:
25:
860:
859:
665:Automatic braking
375:978-1-133-42068-2
173:In this case the
150:Trail or trailing
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850:
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804:Outline of tires
539:MacPherson strut
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256:Vehicle dynamics
246:Toe (automotive)
217:American English
47:An example of a
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740:Hydraulic fluid
735:Hydraulic brake
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642:Torque steering
637:Rack and pinion
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589:Wheel alignment
504:Double wishbone
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221:British English
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183:pneumatic trail
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819:Whitewall tire
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730:Engine braking
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680:Brake bleeding
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632:Power steering
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584:Watt's linkage
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554:Shock absorber
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519:Hydropneumatic
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436:control system
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205:Main article:
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167:shopping carts
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809:Rostyle wheel
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775:Tires (Tyres)
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750:Parking brake
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745:Inboard brake
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579:Unsprung mass
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179:contact patch
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65:steering axis
62:
58:
50:
45:
29:
21:
789:Custom wheel
760:Vacuum servo
695:Brake lining
617:Caster angle
616:
574:Trailing arm
499:De Dion tube
489:Car handling
484:Camber angle
444:Part of the
443:
399:
384:
364:
357:
346:
335:, retrieved
329:
323:
315:
309:
302:
292:
290:
284:. Retrieved
275:
241:Camber angle
225:
210:
192:
172:
163:caster wheel
160:
157:
153:
144:
135:
129:
118:
115:Arthur Krebs
113:
105:
101:
61:castor angle
60:
57:caster angle
56:
54:
824:Wire wheels
794:Drive wheel
784:Alloy wheel
690:Brake fluid
569:Torsion bar
549:Panhard rod
529:Leaf spring
509:Hydrolastic
494:Coil spring
771:Roadwheels
710:Drum brake
705:Disc brake
685:Brake fade
647:Understeer
559:Swing axle
474:Axle track
456:Suspension
446:Automobile
337:January 5,
286:2009-12-25
267:References
213:head angle
103:vertical.
93:ball joint
77:motorcycle
627:Oversteer
594:Wheelbase
564:Toe angle
534:Live axle
479:Beam axle
351:ESPACENET
867:Category
852:Category
604:Steering
513:Hydragas
230:See also
83:, other
814:Spinner
622:Kingpin
434:Chassis
291:caster
195:aligned
175:lateral
110:History
97:kingpin
85:vehicle
81:bicycle
49:chopper
33:
842:Portal
799:Hubcap
657:Brakes
448:series
372:
261:Caster
251:Trail
136:trail
132:trail
71:in a
69:wheel
469:Axle
370:ISBN
339:2021
161:The
55:The
165:on
73:car
59:or
869::
289:.
223:.
79:,
75:,
515:)
511:(
426:e
419:t
412:v
392:.
378:.
293:n
35:—
Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
