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pliers likely to chew the rim up due to serrated jaws. I've fixed worse with an adjustable spanner, nice wide flat faces dont chew up the rim.
I did this to a Crossmax Sl (so a very similar rim)
I had a length of folded inner tube on either side of the rim/lip then clamped on some mole grips. It pulled our in seconds and has been ridden tubeless for the past 4 years.
At the time I was gutted. I though the rim would need to be replaced.
Vice with soft jaws in.
Gives you the length over the whole edge of the rim and you can do it very gently and smoothly.
I straightened worse on a DT5.1 with an adjustable - just look out for cracking where the metal has been bent and rebent. Keep an eye on it after straightening as well

