Are either of the above tyres any good?

Iain

they are both really light… that makes them good in my books.

They're completely different tyres.

Race King is one of the fastest tyres out there, but hopeless in mud.

Speed King is OK as an all terrain tyre but I prefer a Nobby Nic.

RK is puncture prone and needs Flataway tape ideally.

I run a Mountain King 2.4 on the front and a Race King 2.2 Supersonic on the back. Not had any issues with the RK, they are super light so I thought they may tear but so far so good. The RK offers surprisingly good grip even on wet grassy climbs. I have run RK's on the front and rear but I like t throw the front at stuff and it was a bit lose. A good option or a light setup would be a SK on the front and a RK on the rear.

Mountain Kings are great but 2.4 might not fit between the stays when fully pumped up so go for 2.2

speed kings are my fav tyres for round here, and seem to last well if you're easy on the back brake

Schwalbe work better tubeless if that matters! I prefer the Rocket Ron to the Speed King.

Can't get on with speed kings .. thin carcass and bendy knobs feel very vague when cornering IME .. not used race king (just stay away from mountain kings!!)

Race kings are THE tyre for hardpack XC.

running innertube race king protections 2.2 front and rear for dry weather up here in ludlow, shropshire. at 50psi grip very well in dusty singletrack, over roots, on grass, big rocks. pick up speed fast when they're rolling, really happy with them.

went out after 3 solid days of rain expecting them to be sliding all over the place, but they didn't. lowered the pressure very slightly to around 45psi and got me through with just a few skips on wet root step ups.

impressed.

Wow thanks for all the responses I thought it would be dead due to it being another tyre thread.

Iain

+1 for Race Kings, 2.2 are a lot better than the 2.0 although clearance can be a bit tight in some frames, didn't really fit my old frame, new one is fine.
Tried speed kings, they are ok, but Race kings are miles better, I use mine in all conditions, only changing the front to a Nobby Nic when it really wet. If running the 2.2's ignore the recommended pressures on the side, it makes them feel horrible, but at run lower pressures they are amazing.

both are great,both are fast. speed king 2.3 ss is better than the 2.1 and pretty much the same weight.race king is huge!other contis seem smaller size than stated; mk's etc. i run them ghetto tubeless for xc

I struggled with the speed kings that were already fitted on my bike. As soon as the going got slightly greasy they were all over the place. No good on wet clay, mud, or slippery roots (IMHO).

Frickin fast in the dry though…

Only tried the Speed Kings but like them. I just went for the cheap wire bead ones and they seem fine.

If u do a lot of inter-linking road sections or ride in very rocky areas the rear won't last long.

"I'm speed king see me fly"

Use speed kings tubeless on stans olympic.

Speed kings are the fastest tyres I've ever used by miles, they are also not good in the wet at all.