My father has a 08 FXSTC Softail custom 96 cubic inches; he upgraded it to the 103 kit and is looking for a replacement battery. We’ve heard Gel batteries are a better option to go with. I guess what I’m trying to ask is that a true statement and if so, what size and type of battery fits his motorcycle? Are Yuasa batteries good choice for my dadâs Harley? Please advice appropriately. It is supposed to be a Christmas present for my dad, so any information regarding this would help. I hope to hear soon from your side. Thanks.