I need some help in choosing batteries.

I ran two 12v regular car batteries for about 3 months until they pooped out, that was a couple months ago and I've been busy at school since. I tried to never go beyond %50 dod and to charge them immediately after use. I was able to go 15 miles and not go below %50 dod. All in all not bad for $20 each at the salvage yard. I've got a little over $2,000 saved for a motorcycle but nothing great is jumping out at me and all I wanted it for was to go the 8 miles to school and the 8 back to save on gas. So I'm dusting off the bike. I tore it apart and had everything shot blasted. I'm dead set on buying a tig welder and hitting everything that I sticked last time. I'm looking at getting some low rolling resistance tires and maybe a disc brake. My plan is to spend $150 for two wet deep cycle batteries that are a little smaller than the ones I had on there last. What do you all suggest I get in the way of batteries? Thanks-Ryan