- Tire Functions and Basic Structures
- 14 Tire Main Function
- 2General Differences between Radial and Bias
- 3Advantages of Radial Characteristics to Bias Tire
- 4Advantages of Tubeless Radial to Tubetype Radial
- 5Radial Construction and Its Functions
- 6Tire Size
- 7Pattern Tread of Tire
- 8Speed Symbol and Speed Limit Table
- 9Load Index and Load Capacity Table
- 10Groove Depth
- 11Tire Rim
- 14 Tire Main FunctionTire has very significant role in driving. Compared to other spare parts, pneumatic tire is like air bag with its construction designed following road surface and various types of vehicles. Tire's main functions include as follows:1. Supporting ⁄ holding up vehicle load
2. Forwarding the wheel function and controlling vehicle's direction
3. Forwarding motive force and braking of the vehicle on the road surface
4. absorbing shock from road surface
- 2General Differences between Radial and BiasTire Construction Basic StructureTire construction structure is designed to reach intended performance characteristic and pursuant to objectives of usage or utilization, namely according to road condition and type of vehicle, however, in general, tire construction can be described as follows:Radial Tire
Radial construction consists of body ply with its thread arranged vertically to tire diameter.Bias TireBias construction
n consists of body ply with its thread arranged in cross with diagonal direction one another. - 3Advantages of Radial Characteristics to Bias TireConstruction of Bias/Tubetype Tire
Construction of Radial Tire
AdvantagesRADIAL TIRESSPEEDRadial speed rating is generally higher than that of biasENDURANCERadial speed rating is generally higher than that of biasCONTROLRadial has higher traction and stability both for straight and bend roads.FUEL CONSUMPTIONUtilizing radial construction, radial tire has lower rolling resistance than bias, so that fuel will be saved due to smaller energy release.APPEARANCERadial is more attractive viewed from style, wall design, and tread than bias. - 4Advantages of Tubeless Radial to Tubetype RadialIn general, radial tire has tubeless construction. Tubeless mean any tire not requiring tube and, as its substitute, the tire is layered with inner liner made of airtight rubber material.Tubeless Tire
Tubetype Tire
Advantages of Tubeless Tire- Lighter than tubetype tire
- Safer when it is affected by sharp object (nail)
- No risks of exploding due to heat caused by frictions
- 5Radial Construction and Its Functions

- SidewallProtecting body ply (carcass) on tire side and also functioning as place for putting tire important information.
- Gum StripSpecial rubber put on steel belt edge functioning as shock absorber of steel belt thread tip.
- Cap Strip/Cap PlyAny textile thread with angle 0 layered by rubber. Utilized for twisting belt that the steel belt will not change its angle and diameter due to centrifugal force when the tire is used at high speed. Function:
- to improve tire performance at high speed
- TreadTread is main part of tire directly contacting road surface. It defines tire life, provides with tire appearance, and creates good traction on wet road.
- Apex / FillerApex is in a triangle in couple with bead and they have different functions as:
- Handling and stability
- Blank space filler at body ply fold.
- Inner LinerOne part of tire located at inner part, functioning as substitute to tire tube and made of mixed airtight rubber.
- Steel BeltA steel belt liner that has been laminated by rubber and arranged by intersection. Belt provides with tire reinforcement and it has more stable and flexible physical characters. Its functions as:
- Body ply holder for obtaining tread so that it can step on road perfectly.
- Strengthening body ply (carcass) so that it will always be able to defend its round from of road construction
- Bead WireIts form is carbon steel wire layered with hard rubber and then formed as proper circle in layers. Its functions:
- ply lock to attach to rim.
- Body Ply (Carcass)Body ply is main part of tire in the form of layered sheet consisting of polyester or nylon or wire thread with rubber liner. Functions of body ply are as follows:
- Tire frame.
- To hold tire pressure.
- To absorb vibration of road.
- Sidewall
- 6Tire Size
P 205 / 75 R 15 98 H XL205Nominal Section Width (mm)75Aspect Ratio (Series)RRadial Construction15Rim Diameter98Load Index (750kg)HSpeed Index (210 km/h)XLExtra Load
245 / 75 R 15 C 120/116 L245Nominal Section Width (mm)75Aspect Ratio (Series)RRadial Construction15Rim DiameterCLoad Range (6PR)120/116Load Index
(Single/Dual = 1,400kg/1,250kg)LSpeed Index (120 km/h)
31 x 10.50 R 15 109 Q31Overall Diameter (inch)10.50Nominal Section Width (inch)RRadial Construction15Rim Diameter109Load Index (1,030kg)QSpeed Index (160 km/h)
19 / 57 - 1519Nominal Section Width (cm)57Overall Diameter15Rim Diameter - 7Pattern Tread of TireAsymmetrical Tread Pattern
Good stability & wet handlingAsymmetrical tire design has a different tread pattern between the outside and inside section. It aims to keep the stability of the tire balance. These designs give excellent maneuvering; with better noise level than high performance tires.Directional Symmetrical Tread
Better grip on wet roads,
good cornering at speed on a drySymmetrical tires with rotation have the same tread pattern between outside and inside sections. The symmetrical shape of tires clearly can be seen on rotation. The rotation direction can be seen on the side of the tire. These designs give excellent performance on wet roads. Do not install a symmetrical tire upside down, forcing this installment would endanger the driver when the car is used on wet roads.Asymmetrical Tread Pattern
Low noise, tire rotationSymmetrical tire designs have a simmiliar tread pattern in between outside and inside sections. It makes it easier and more flexible for the driver when handling the vehicle. - 8Speed Symbol and Speed Limit TableSPEED
SYMBOLSPEED
(km/h)A15A210A315A420A525A630A735A840B50C60SPEED
SYMBOLSPEED
(km/h)D65E70F80G90J100K110L120M130N140P150SPEED SYMBOLSPEED
(km/h)Q160R170S180T190U200H210V240W270Y300 - 9Load Index and Load Capacity TableLOAD INDEXKg71345723557336574375753877640077412784257943780450LOAD INDEXKg81462824758248784500855158653087545885608958090600LOAD
INDEXKg916159263093650946709569096710977309875099775100800LOAD INDEXKg101825102850103875104900105925106950107975108100010910301101060 - 10Groove DepthGroove or Tire Pattern Depth
Groove or Tire Pattern Depth is depth measurement of tire pattern - 11Tire RimRim Width
Rim width is the measurement on how wide of a tire you can install. Each tire has specification of rim width range that be mounted


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