Do JK Steel Belted Radials help in fuel saving?

JK Steel Belted radials give more than 5% fuel saving.

This is made possible by the structure of radial tyres. Ordinary tyres have a criss-cross ply construction. The cords in successive layers tend to move against each other in a scissor-like motion causing extra internal stress.

This is absent in radial construction. Cords in radial tyres are laid radially. They flex easily - without internal stress. This means less energy is required to move the vehicle. You save precious fuel.

An ideal tyre fitment arrangement would be to have all four tyres as radials. If you use only two, fit them only in the rear.



Why should you use JK Radial tubes with them?

JK Radial tubes have several features which make them ideal for radial tyres.

• Made of Butyl rubber for better air retention
• 30% higher joint strength Ability to withstand higher rate of deflections
• Higher gauges
• Shaped to fit snugly into JK Radials. No excess stretch to cause loss of air

Do retreaded radials give better mileage than retreaded ordinary bias tyres?

There are thousands of retreaded JK Steel Belted radial tyres in operation. Retreaded, they still give much more mileage than retreaded ordinary bias tyres. It is necessary to remove them for retreading while there is still 2mm of tread pattern life, when tread wear indicators appear, as shown in the picture. These TWIs show it is time to retread the tyre.

It is recommended to retread radials by the latest procured process.

Do radials enhance the comfort level while driving?

Yes, JK Tyre radials provide a bonus to motorists in the form of greater comfort. The supple sidewalls of the tyres act as mini shock absorbers. They ensure that less shocks pass on to the suspension. This means that your ride is more comfortable, even at high speeds.

Greater Comfort With Radials




Just how vital is correct inflation pressure? What damage does under-inflation cause?

It is very important to correctly inflate tyres. Do not estimate tyre pressure by appearance. Under-inflation causes fast tyre wear, steering drag, excessive fuel consumption and tyre failure. Over-inflation causes hard riding, damage to suspension and steering and uneven tyre wear.

Check pressure with an accurate gauge when tyres are cool. Regularly check your pressure gauge with a standard gauge for accuracy.





What are the common reasons for tyre damage?

A flat spot can be caused by heavy braking which makes the wheels lock and scrub the tyre along the road surface.

Feathering is caused by bad wheel alignment, excessive toe-in or toe-out of the wheels.

Uneven wear of the tread is due to bad wheel balance, or a fault in the suspension, steering gear or bearings.

Many people fit their cars with wider tyres for aesthetic reasons, are there any technical advantages / disadvantages of doing so?

Although correct tyre size for normal running is the one recommended by vehicle manufacturer, For special purposes vehicle performance can be improved by selecting wider tyre with lower profile, which means maintaining same overall diameter of the tyre, lowering aspect ratio, thus increasing the tyre width. This is called up-sizing or up-stepping.

There are some safety guidelines, which must be followed while upsizing, i.e., overall dimensions of the tyre must fall within certain limits. While selecting a high performance tyre following must be observed:

1. Clearance
   Ensure that any of the tyres does not foul with the vehicle body under any conditions. On vehicles with McPherson strut suspension, there is very much a chance that super fat tyre fouls with steering linkage. Also the tyre should not project out of the vehicle body, thereby increasing overall width of the vehicle, increasing chances of an accident.
   
   
2. Speedometer and odometer error
   Speedometer / odometer are connected through propeller shaft of your vehicle and are calibrated for a particular wheel overall diameter. Changing overall diameter of tyre much, may lead to erroneous readings by speedometer and odometer.

In case you observe that tyre overall diameter is decreasing much, you can increase your rim size. Use following calculation to select correct tyre size for larger rim.

For every 1-inch increase in rim diameter, add 20mm to tyre width and subtract 10% from aspect ratio. But be sure to check PCD of rim and fouling of new tyre/ rim assembly with other parts



Is there a chance of tyre burst while running at high speeds?

Every tyre has a speed rating, which indicates the max. speed to which you can run the tyre. See " tyre terminology " section on this website for details on speed rating.





Two of the tyres on my car are worn and need replacement, where should I fit new tyres ?

Many dealers and customers alike are of the view that when two tyres on a car are to be replaced , they should be fitted in front. This was the case few years ago, when it was felt that conrtrol of the vehicle was more critical to front deflations and therefore new and less vulnerable tyres should be fitted in front.

But the modern recommendation by tyre industry is "New tyres to rear". This applies to both front and rear driven vehicles. Primarily its justification is increased safety particularly in wet conditions. Partly worn tyres have poor water drainage, leading to aquaplaning and thus tendency to oversteer and loss of control. Similarly straight line braking in wet can be adversely affected.

"New tyres to rear " Principle may not apply to following cases:

1. Where front and rear tyres have different sizes.
2. Where two new tyres are of lower speed rating.
3. On certain 4x4 vehicles, where it would result in significant difference in tread depths.

What inflation pressure should I have for my tyre?

Correct inflation pressure is indicated on vehicle placard/ owner's manual of the vehicle. However for extreme low traction situations you may have to decrease inflation pressures. This increases foot print size of the tyre and floatation ability and aids traction. But NEVER DEFLATE YOUR TYRES UNDER 16 PSI and inflate to original pressure as soon as you return to tarmac.

Also you should keep in mind that load carrying capacity of tyre is proportional to its inflation. Which implies that Inflation pressure on your tyre should be proportional to the load. Excessive inflation leads to low shock absorbing ability of tyre, impact failures or other casing failures, this also leads to excessive wear in centre. Under inflation will cause excessive wear in shoulder, heavy steering and poor handling.



A few parts on tyres on my car are wearing faster than other parts, what can be the reason?

This situation is called spot wear and can be attributed to following:

1. Dynamic imbalance of tyre/ rim assembly.
2. Sudden braking and rapid starting.
3. High run out in tyre/ rim assembly.

In case tyre is wearing diagonally, i.e., wear is starting from one side and progresses to other side as you move along the circumference, following may be the reasons:

1. Faulty suspension.
2. Improper wheel alignment.
3. Faulty rotating parts like brakes, etc.
4. Bent beam axle.

How tubeless tyres are different from conventional with tube tyres? Which is more safe?

Tubeless tyres have a liner of specially made rubber over innermost layer of the tyre. This liner gives the tyre air tightness and sealing properties as good as a tube, not only that if a nail pierces into the tyre, liner engulfs it and prevents air from leaking out, air leaks only very slowly when the nail is taken out.

Thus, come what may, a tubeless tyre never goes flat all of a sudden and hence is more safe.