The SAFETY TECHNOLOGY BUILT AROUND THE CARBON WHEELS SUPPLIED BY IRWIN CYCLING
WHY IS HEATING OF THE CARBON RIM IMPORTANT AND WHAT IS TG?
Carbon rim is laid up by pre-preg carbon fiber weave. At 180 degrees C, a phenomenon called ‘Glass Transition’ (known as ‘T.G.’) will take place where the resin will start to transit from a solid state to a liquid state. This is potentially a big issue for carbon bicycle rims. The heat is transferred from the braking surface into the tire and inner tube can rapidly become excessive causing failure
DOES HIGHER TG MEAN BETTER SAFETY AND PERFORMANCE?
Although carbon rims with higher TG can withstand higher temperature. It does not prevent tire for curing at high temperature. Irwin believes it is important to keep the rim and its braking surface cooler at around 130℃.This temperature is much lower than the inner tube blow out temperature (curing temp. 170℃).Irwin delivers this technology in our carbon clincher road wheel product line.
How Does IRWIN CYCLING measure the rim safety and performance levels?
Answer: The ‘DMA Report
The DMA report shows that a high ‘TG resin’ can bear higher temperatures, but the bonding strength of carbon layers starts to decline at 130℃.The bonding strength of carbon layers will keep only 20% of their original strength when temperature reaches TG point 180℃
Note The Dynamic Mechanical Analyzers (DMA) is used to measure the mechanical properties of materially difference at different time, temperature, and frequency. When the carbon rim is under braking process, the temperature of braking surface will rise and the resin will change the mechanical properties. That’s why we do this test and check the difference.
HOW DOES IRWIN KEEP THE BRAKING SURFACES COOLER?
Irwin’s “Ceramic fiber composite reinforced braking surface”, keeps the braking surface cooler and below 130℃.
How does it keep temperatures lower than other carbon rims in the market? Irwin’s Ceramic fiber composite reinforced braking surface isolates and greatly reduces heat transit into the tire. This increases safety and performance of the rim and tire under heavy braking load when you need it most! This enables the rider to ride safely and maintain peak performance without over-heating from “extreme” temperatures generated by heavy braking loads .By identifying the scientific properties and working with leading edge science, Irwin delivers safety, reliability and performance through our products. This is only one of the many features that set’s Irwin, quality, reliability and performance apart from our competitors.
FOR MORE INFO ON THE WHEELS info@irwincycling.co.za