Interloc Racing Design has an exclusive with Panaracer to market 29-inch versions of the ubiquitous FireXCPro. It features multi-stepped crown tread for added knob support and a pseudo speed ramp effect. The single compound tread is available with either black or red sidewalls. The IRD is a really good tire that unfortunately didn't arrive in time to make MBA's Tire Special in the September 2008 print Mountain Bike Action Magazine. Following is how it would have scored.
IRD FIREXCPRO 29'er 2.1
PRICE: $59.99
COUNTRY OF ORIGIN: Taiwan
WEIGHT: 1.6 pounds
ACTUAL SIZE: 2.2 inches
ROTATION: F/R directional
PEDALING EFFICIENCY: ***
CLIMBING BITE: ****
BRAKING BITE: ****
CORNERING GRIP: ****
LOOSE DIRT PERFORMANCE: *****
COMMENTS: It was necessary to run the rear tire in the recommended front direction to achieve this great score. In the front rotating direction the FireXCPro 29'er pedals more efficiently and bites much
harder braking over loose surfaces. Overall the IRD has proven to be a very tough tough, trail-worthy tire.
That score firmly puts the IRD FireXCPro 29'er into the 6th position on MBA's list of the top ten 29-inch tires. That means the former 6th to 10th place finishing tires move down one spot, and the Bontrager Jones ACX 2.2 gets knocked off the page.
We liked the IRD FireXCPro 29'er so much that we ended up converting it to tubeless on a Mavic C29ssmax UST wheelset reviewed in the upcoming October 2008 issue. The IRD immediately Stan's-converted tubeless. We ran it this way and with great results at 25 psi until... the tire just blew off the rim today while jumping. (It was in the back touching down from a crossed-up flight, and allowed for us to easily ride it out.)
The Kevlar bead needs to stretch or break for the tire to come off a rim like that. Once a tire does blow off a rim MBA recommends throwing it away; don't even use it with a tube.
Other than bead failure, a tire can pop off a rim when converted tubeless if the rim is on the small side of the acceptable manufacturing diameter range. Or the tire could be on the large side of the tire size range. However, the tire bead feels like it has a weak spot after it blew off the rim. We always take our tires up to 40psi when converting tubeless. If the tire holds on at that pressure setting it's a good indicator that the bead is strong enough. After a few minutes we drop pressure down to the 25psi that we use as a base setting for tubeless tires. This proves that our particular FireXCPro 29'er had a weak bead. This would be a fluke for Panaracer, which has quite a good reputation for producing tires that can be reliably converted tubeless.
The fact that one of our tires failed has no affect on its performance score. The IRD FireXCPro 29'er is designed to run a tube and was originally evaluated with a tube.
| 
