The performance of a tire varies according to the materials used and the production process. We will explain a few concepts that will help you identify products of higher quality.

CHALLENGE TUBULARS “HAND MADE”:

All tubular and open tubular produced by Challenge are special products. Machines are not able to produce them and the manual skill required in each step to obtain a good quality standard is very high.

The casing is produced with the latest technical materials like Corespun (a cotton and polyester combination).  Corespun is a thread from which we obtain a very supple and strong casing with low weights. The casings have a high TPI count that can reach over 300 tpi. Our production process avoids any vulcanisation process to enable all materials to keep their suppleness and flexibility.

The tread is slowly hand glued on the casing which is previously mounted and inflated on a rim. By using this method the tread is relaxed on the casing and does not suffer any  tension  when inflated. The result of this is a lower rolling resistance, increase in comfort, more precise handling of the bike and better grip. Hand made tubular are well known by professionals and is this type of tire that is preferred for the long stage races.

To give the best possible grip in curves Challenge uses the most updated materials to obtain flexibility, suppleness and this results in absorption of irregular surfaces giving to the cyclist  the best possible contact patch. The wheel avoids jumping and the tire will deform and absorb the irregularities acting in some way as a shock absorber. A special fabric is placed between the tread and casing to increase puncture resistance “PPS” (Puncture Protection System) technology.

Comfort means reduction of harmful vibrations for the wrists and neck, these vibrations, will end causing inflammatory problems, as a hard tire will transfer all the vibrations directly to the racer body.

If you have never tried a “hand made” product, go to a local  shop and ask to see one. Touch the product and look at its construction and the side walls. You will immediately notice the difference.

CHALLENGE OPEN TUBULAR “HAND MADE”:

Open tubular differ from traditional clinchers for the construction. The tire is produced just like a tubular and uses the same materials and production process. Instead of being sewed with an inner tube inside, at the end of the process beads are made by folding the casing around Aramid fibers threads. For this reason an open tubular gives very similar ride feel of that of a tubular, mainly if a latex inner tube is used.

Mounting an open tubular on a wheel is the same as mounting a standard clincher but with the advantage of riding a much more comfortable and performing tire.

INNER TUBES:

Latex inner tubes:  Used in all high end tubular thanks to their low rolling resistance. Thinner and more flexible than butyl tubes. The use in open tubulars increases comfort and lowers rolling resistance. Latex is also more resistant to punctures. On the other hand it is a porous material therefore it requires daily inflation.

Butyl tubes: Butyl tubes are generally in the 90 grams area Lighter tubes are available but tend to be more fragile. A softer tube will have a better ride performance. The advantage of butyl tubes is in air retention and a more accessible price.

 DIMENSION AND CONTACT PATCH OF A TIRE:

A tire with narrow section is not necessarily faster. The contact patch to the ground of the tire  section 23 is the same as a section 20. The difference is minimal but in cornering the 23 is able to increase its grip as you bend. The surface increase more and the more air volume of the tire allows the tire to also increase stability. The result is that a 23 mm tyre  is actually  faster than a 20mm one.

Rolling resistance is same or slightly lower on a wider tire.

It is more visible for instance in the new trend of the 29ers in MTB side. This concept is growing as riders try them and find several advantages.  A 29” will have a longer contact patch than a 26” Mtb tire so the section can be decreased. You would use a section 51mm on a 26” wheel but would use a 45mm section on a 29”er. A 29” tire will roll better, contact patch is longer giving better traction and more control. Also, on rough surfaces will climb better of stones, rocks and asperities found on its way.

 PREASSURES AND USE (bar / psi)

Industrial types of tubular need to be used at high pressure and indication is 12bars - 170psi to obtain the same performance or rolling resistance of a hand made product. Such high values are not advisable. The tubular becomes very hard and instead of absorbing the vibration you tend to bounce.  This casue loss of control, increase rolling resistance therefore also grip is lower. The risk of punctures and losing grip is high.

Challenge tubular which are “hand made” use a lower pressure that goes from 7,5 bars (105 psi) to 9 bars (135 psi). At these pressure the tire performs at its best weather it is an open or a tubular. The reason is in the casing. If the casing is able to do its job and that is to flex were needed and to absorb vibrations. The performance of a tire is given 90% by the casing construction and 10% by the compound used. This explains the reason why manufacturers that do not use the “hand made” techology use a lot of marketing and loud names on "special" compounds trying to bring the attention on that specific aspect only.

 CONCLUSION:

What ever product you will buy make sure that it fits your needs. From this quick explanation you can understand better the types of products available in the market and the quality they can offer also in terms of comfort, performance and technology. 

The tires are one of the most important components on your bike and they can really make the difference, if you chose the right product for your needs.