And to expand on that a bit the six separate throttle bodies on the Rune are 32 mm verses the GL1800/F6B twin throated throttle bodies of 40 mm and the VTX1800 uses a twin 42 mm throttle body. The Rune has a different cam than the GL1800, it is a torque cam and while the Rune will beat the GL1800 out of the hole, in the top end the GL1800 will get the to the speed limiter faster.