Based on reports from the field that tires with cotton,
silk, or other natural fiber sidewalls with open tubular
style of construction were degrading quicker than expected,
we launched a study to understand the validity and
prevalence of these claims. As a result of this
investigation, we confirmed that tires using natural
sidewall materials with an open tubular type construction,
are not fit for use with ENVE carbon rims. It is important
to note that through this study, we reached out to many
dealers as well as other wheel manufacturers to see if their
consumers are having the same results as ours. The response
was an unequivocal confirmation that these tires were
fatiguing prematurely and in some cases resulting in crashes
and injury to the rider when the tire sidewall failed or the
tire came off the rim without warning.Â
There are two specific failure modes that have been
documented and are not limited to ENVE rims, rather these
failures have been consistent in our test lab on a variety
of other manufacture’s rims, both alloy and carbon.Â
The first failure is best defined as a cut or wearing
through of the natural fibers on the sidewall of the tire at
or near the rim’s hook bead. Once cut through, the tube
extrudes through the tear and bursts, often unseating the
tire from the rim resulting in sudden loss of control and a
crash. The cutting of the sidewall is the result of soft
fibers (the cotton or similar textile) being abraded by the
harder edge of the rim during the rotational compression
cycles of wheel and tire.Â
The second failure mode is that of the tire itself
stretching off the rim. This is can be caused by a variety
of factors, among them, low bead stiffness, varying tire
diameters, over inflation, or some combo of the three. The
tires most susceptible to this failure are those with a
“handmade open tubular� type construction. Given the
large selection of tires on the market that deliver
excellent performance with reliability, it is our
recommendation that ENVE customers should not pair these
tires with their ENVE wheelsets.
Here are some specific brand/tire models that we DO NOT
recommend:
Vittoria Corsa Non-Tubeless (Not ALL Vittoria Tires) –
This tire features cotton sidewalls in black, para (tan),
and anthracite (gray). This tire has been described to us by
Vittoria as a race day only type of tire and that it is not
recommended for training or prolonged use. This tire has
been the main offender for cut sidewalls. While this one
tire is not recommended for use with ENVE wheels,
Vittoria’s Rubino model tires and the tubeless ready Corsa
Speed have proven safe and reliable in our testing.Â
Challenge Handmade Clinchers – These are Open Tubular
Non-Vulcanized Tires
Models:  Criterium SC S, Strada SC S, Paris Roubaix SC
S, Strada PRO, Paris Roubaix PRO, Elite PRO
Consumer Service/Dealer Communication Recommendation:
1) Do not recommend, promote, or condone the use of the
above “Not Recommended� tires to your ENVE customer.

2) If you know of customers currently riding ENVE w/ a Not
Recommended tire, please contact them and ask them to
replace their tires as soon as possible. If they intend to
ride this combination before replacing their tires,
encourage them to inspect the area of the tire that contacts
the rim’s leading edge for abrasion or signs of wear. If
any signs of wear or cutting are present, reiterate that
they are at risk.Â
Please recommend the following manufacturers to customers:Â

Continental
Hutchinson
Mavic
Schwalbe
IRC
Maxxis
Pirelli
Tufo
Panaracer
Vittoria – Just not the Corsa Open Tubular
Specialized – Only known exception is the S Works
2Bliss 28mm which is not compatible with hookless rims like
the G23 or SESÂ 4.5 AR
Bontrager

If you have further questions, or a specific tire that you
would like to see tested and approved, please contact your
ENVE Dealer Service Representative at 877-358-2869.Â
Sincerely,Â
ENVE Composites

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971