This. And I wouldn't even apply a time line to it. Rather than say a year...I say it is mostly training and how much you do or do not put into it.

To the OP, is weight a factor? Sure. Is it a 100% guarantee of climbing success. 100% no. There are so many factors to quality climbing. Hell, look at pro riders...there are few of them that can do everything well. Some a re known sprinters, climbers, etc.

Train, train, train and then train some more if you want to get really good at climbing. I'd list off all of the things you need to get good at it but honestly, it would take too long. Look up info on it.

Im im beginning my "off season" training this winter and I'm going to focus on climbing...I'm a glutton for punishment I guess...