Choppy idle

[finnishvara]

Hello, first time poster here

My 2011 efi 125 varadero has started having a choppy idle.
The idle stays at 1700rpm 75% of the time, but sometimes it just drops to ~1000rpm as if it were running on only one cylinder. Also, when driving and i pull the clutch in and give it revs so it doesnt drop to idle it sometimes bangs.

High rpm is fine.

 It has been driven 62 000 km, it leaks oil a bit and has a Dominator slip-on, if that's relevant. Oil, plugs and the air filter have been changed ~3000km ago.

What could cause this?

[finnishvara]

Allright, i inspected it closer and found that the bolt tightening the throttlebody to the front cylinder had fallen off. So air leak was the problem. Also added some motul valve & injector cleaner. Now it runs like new.

[brinkcx]

Always nice to hear problem solved and how, thanks