Safety procedures and tips for motorcycle tires.

ATS LTD Newbury (U.K) © 2002

We take them for granted but have you ever thought how much we rely on our tires?

Have you considered the performance we require from them every single time we ride?

To see what I mean, try this exercise.

Hold both hands out in front of you with palms uppermost. Have a good look at them. You are now looking at roughly the area of your tires in touch with the road whenever you ride your bike!

In other words, that's the amount of rubber between you and eternity as you do the normal things bikers do. Like winding past that big lorry in the pouring rain, tucking in tight, and keeping the power on in a right hander or, possibly, stopping on a tanner when that Scandinavian looking car has decided, at the last second, to turn right across your path in front of you.

Remember, the brakes stop the wheels but it's your tires that stop the bike!

Now give a thought to the forces you are putting through those two bits of rubber.

Think of the heat generated as the speed rises and of the flexing needed to cope with the handling ability of a modern Superbike.

You are now beginning to realize why the development and technology that has gone into those pieces of rubber has had to be very special.

The truth is, bike tires have developed so much in recent years that they can now usually out-perform even the best of riders on the greatest of machines and in the worst of weathers! They won't often let you down. They will nearly always perform well for you. But they can only do so if you give them a fighting chance.

Making sure you have the right tires for the bike and having them professionally fitted, correctly balanced and properly maintained is every bit as important in your overall strategy as buying the right clothing and getting the best training.

SELECTING THE APPROPRIATE TYRES FOR YOUR BIKE

Unless you are always going to replace your tires with exactly the same make and type that were fitted by the manufacturer when the bike was new, you are going to need to know (or ask a man who does) a bit about the huge choice of tires on sale and what specs mean when the time comes to buy the baby new shoes.

The days when all you needed to know was the size and how much they cost have long gone. Modern tires come in so many varieties with so many differing performance values even the experts have a job keeping up with it all.

Some rules are fairly general. For example

Spoked wheels (with notable exceptions) can only take tubed tires.

Radial tires (again there are one or two exceptions) can rarely be fitted with a tube.

Front tires go on the front, rear on the rear ONLY.

The speed rating of the tire must match the capability of the bike i.e.

Then you have to watch how radials, bias belted and cross ply tires are mixed. It's better to avoid mixtures if you can, but the following is law.

Bikes come in all shapes and sizes. Some rims won't take some makes or tires and some swinging arms are too close to permit some tires to be fitted. You'll need to know what can go on your bike - and what is going to happen once that lovely new radial comes under load!

Then there is the difference with the compounds to be considered. Mixing hard (long wearing) and soft (maximum grip) tires on the same bike can be okay but equally can be disastrous if they are not compatible or on the wrong wheels.

As if all this wasn't enough, some tires are not warranted for road use at all. Then different parts of the world need different tires dependant on the climate and road conditions. Ask any Gold Wing rider who bought those 'good value' American tires a while back and 6,000 miles later found they had worn out! Wings are normally good for up to 15,000 miles but European roads are not the same as their counterparts in the States.

FITTING AND BALANCING

Basically, there is little difference between fitting a motorcycle tire and fitting any other sort. The real skill comes in knowing what to look for and knowing how to accomplish the tire change without later endangering the rider or damaging the bike.

  Most riders should know how to take out a wheel but there are still many who don't. There is a potential for enormous damage to be caused if this is done badly. Modern wheels can be delicate and very expensive things; they can have coatings on them that can be damaged, torque settings can be critical and great care must be taken with the brake mechanism.

If there isn't a mobile fitter or a mechanic who can get out to you, you really need to know how to get the wheel out and put it back properly. It would pay to find out how to do this and, if your bike has only got a side stand, you may also be wise to invest in a paddock stand for your garage. One-wheeled bikes don't tend to last too long on side stands!

Magnesium and alloy wheels can be a problem when removing tires. They can bend and distort if not handled carefully. The experts use the proper equipment to ensure no damage is caused.

When fitting a tire (especially tubeless) it is important to ensure the bead line is visible around the whole of the circumference.

It may be necessary to put a bit of pressure into the tire to do this (usually you hear a pop when the bead locates) then adjust it back down. However it is critical that the pressure is not excessive or the tire could explode. You should use a 'cage' when blowing up tires if at all possible.

While the wheel is out.

This is the time to have a look at the bits you can't always get at. For example the rim should be inspected for damage or rough edges, wheel bearings can be checked for play and spokes can be cleaned and checked for tightness.

Balancing

Modern tires are fairly well balanced right from the start (when properly fitted) but it is still advisable to have the front wheel balanced to get rid of any lingering vibration. These days this can be done at the same time the tire is fitted. There was a time when it was no good balancing a wheel until the tire had suffered a bit or wear!

Properly equipped motorcycle tire fitters will have access to a balancing machine and it really is advisable to spend the extra couple of quid getting them to use it.

Running In

This is really important. The number of riders who have crashed on new tires is legion. Tires need to be 'run in' before they should be expected to cope with hard riding or braking. The first 50 to 100 miles is critical. Ride smooth and slow for this period and your tires will perform at their peak for the rest of their lives.

INSPECTION AND MAINTENANCE

It is mandatory that your tires conform to the following rules:

·         Tires must be kept in good condition without bulges, splits or breaks.

·         Pressure must be maintaining to recommended levels.

·         There must be 1mm of tread depth throughout a continuous band measuring at least three quarters of the breadth of the tread around the entire circumference OR if the grooves of the original tread pattern did not extend beyond three quarters of the breadth of the tread any groove, which showed in the original tread pattern must have a depth of at least 1mm. AND

·         The base of any groove, which showed on the original tread pattern, must be clearly visible.

What you should be on the Look-Out for

·         Foreign objects sticking out of the tire (esp. bits of glass or flint in the grooves of the tread).

·         Cracks in the side walls - very important if the bike has been laid up for a while.

·         Tread depth (see above)

·         Pressures - these need to be checked while the tires are cold at least every fortnight using a good quality tire pressure gauge.

N.B. the gauges found in most petrol stations are notoriously unreliable.

Uneven wear in the tire - especially any 'flattening out' in the middle, which leaves a ridge.

More about Pressures

This is the first thing you should check if the bike starts handling badly. Even a couple of pounds difference in the pressure can make a huge difference and tire wear becomes ruinous. The effect of over or under inflation can be shown thus:

Also, if you go to a different make from the one originally fitted you may find the pressures have to be different as well. Find out what you should be running on when you get the tire fitted. Finally, tires can easily absorb oil and grease from the road. Modern tires are very durable but their life is not indefinite. The best advice all the experts give is: use them, look after them and change them regularly.

PUNCTURES AND REPAIRS

It's the breakdown we all dread but it's as inevitable as the rain that always follows hours of cleaning and polishing! Thankfully, these days we don't see so many of those front wheel, high speed blow outs of yesteryear but anything that inflates is liable to be punctured and the problem of sudden deflation is still with us.

Tubed tires are straightforward. As long as the tire itself is not badly damaged it can usually be repaired and all you do then is replace the tube (do not repair a tube - it is never worth it!). Remember repairing the tire is just as important as replacing the tube. Imagine the water and muck that can be forced through the hole and start acting between the tube and the tire itself and you'll get part of the reason.

When repairing tubeless tires there are certain requirements. Most experts will always use a 'mushroom' repair to completely fill the hole and very few are happy to simply apply a patch to the inside. The reason they will give you comes from the danger of a patch getting 'lifted' by water forced through the unfilled hole on the body of the tire.

NB Some punctures simply cannot be repaired. Side wall punctures and those where structural damage to the tire has occurred are two examples.

Radial Tires. It may seem a bit excessive but if you get a puncture in a radial the advice will almost always be to 'write off' the tire. Radial tires are built with a continuous belt around them below the rubber. If the belt is damaged the tire could distort under extreme use (as you get with a modern Superbike) and the puncture could re-develop with disastrous consequences. Chris and Peter will simply refuse to repair a tire if there is the slightest danger of this occurring.

Foreign Objects

If you find a nail or screw sticking out of your tire the advice is: leave it there! Take off the wheel and get down to the tire shop (or call a mobile fitter). You never know, the tire may be capable of being saved.

Puncture Proofing

There are substances on the market that you put into your tires and just forget about punctures altogether. Some of these products are wonderful, some are not. The best thing to do is get expert advice before adding anything that can affect your tires in any way at all.

Tires have a lot of “writing” on and it is useful to know that every producer has a specific code imprinted on the wall of the tires to determine the date of construction: ask the dealer to explain the Time Code of the brand you buy so you will know the age of your “new” tires. Other marking or symbols are reported on the table below taking a radial tire as example.