Radio-loud quasars (RLQs) are known to produce excess X-ray emission, compared to radio-quiet quasars (RQQs) of the same luminosity, commonly attributed to jet-related emission. Recently, we found that the HeII EW and $alpha_{rm{ox}}$ in RQQs are strongly correlated, which suggests that their extreme-ultraviolet (EUV) and X-ray emission mechanisms are tightly related. Using 48 RLQs, we show that steep-spectrum radio quasars (SSRQs) and low radio-luminosity ($L_{rm R}$) flat-spectrum radio quasars (FSRQs) follow the $alpha_{rm ox}$--HeII EW relation of RQQs. This suggests that the X-ray and EUV emission mechanisms in these types of RLQs is the same as in RQQs, and is not jet related. High-$L_{rm R}$ FSRQs show excess X-ray emission given their HeII EW by a factor of $approx$ 3.5, which suggests that only in this type of RLQ is the X-ray production likely jet related.
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