Had this bike out literally twice (ns core 2) and last night had chain suck so bad the chain was going all figure of 8 style. How and why is this happening already!?

They often put cheap chains on new bikes ‘cos no-one is going to check the spec.

Look at the chain and see if is lateral straight or has any kinks.

Put a better chain on before any wear takes place.

My first bike, a kona muni-mula, did this.

brand new as in whole bike straight out the shop??

I’d have a very close look at the chain for a stiff link

Yep, straight out of the shop. Just been spinning the cassette with the wheel off and it’s not turning overly freely. Bit of dirt in there maybe?

did they prep the bike for you?
Have you de-greased the chain from the protective stuff it is packed with, out of the bag. If not, its just a claggy mess of mud and really sticky grease, so no wonder it sucks!

Chain may be poorly fitted and therefore have a stiff link?

More likely if it’s a Shimano with a joining pin rather than a link.

I’ll give everything a good wash and lubing and see how we go.

Thanks folks.

Don’t degrease the chain. Just wipe off any excess grease and then lube it with some normal chain lube.

Had a very similar issue on a new bike. Turned out to be a be a rough tooth on the front ring from a rock strike on a first outing but by the time I’d had 3 bad chain sucks the chain was beyond repair.
I don’t think I helped matters cleaning the chain with a degreaser in a chain cleaning device. The SRAM chains state that the chain should be greased back up asap if you have to use a degreaser.
The Mucoff spray on lube is horrible stuff and a bitch to get of your tyres when you over spray but it does the job of getting the grease back in.
The problem you’ve got now is that if you have stiffened a link, when you clean the chain up and lube it you won’t notice anything on a quick test run. As soon as you take it out and get it on the track and get some dirt in the link it will stiffen up and suck again.
If you’ve only had one chain suck you should be able to clean it up, re grease then lube but if it happens again after that I’d go for a new chain.