Absolute Anime

This is non-hyper mode bolt gundam.
Grizzly is mad strong and has 2 axes while bolt gundam has two energy flails. Bolt is faster and stronger, but grizzly is equally strong, if not stronger. Also, grizzly gundam fights fior revenge, while bolt gundam fights for nothing.

Erm... is the Grizzly Gundam the Lumber Gundam? (see the link)
http://www.mahq.net/mecha/gundam/g/gf13-037nca.htm
If it is, I'd say the Grizzly(Lumber) Gundam would win in a straight out battle, as it is the most powerful in the tournament (in raw power), see the link I gave you for more information.