SpaceFibre (ECSS-E-ST-50-11C) is a very high-performance, high-reliability and high-availability network technology specifically designed to meet the needs of space applications. It requires serial transceivers for implementation. The Microchip RTG4™ FPGA is equipped with 24 serial transceivers, each capable of supporting rates up to 3.125 Gbit/s. STAR-Dundee provides SpaceFibre communication IPs optimized for deployment on RTG4 FPGAs. Multiple lanes can be grouped to achieve aggregate bandwidths up to 25 Gbit/s. In this paper we present the results of radiation tests examining heavy-ion single event effect behavior of the serial transceivers used on the RTG4 FPGA while implementing SpaceFibre data links. We study both the native upset rates of the RTG4 transceivers and the resulting SpaceFibre link error rates. Results show that the use of SpaceFibre mitigates the effects of radiation allowing to create reliable links in harsh conditions.