Have Necky Manitou 14. Love kayak, but seat is uncomfortable. After about 45 minutes, my lower back starts hurting, and it gets worse and worse.
Thanks for reaching out! We're sorry to hear you're experiencing discomfort with the seat in your kayak. There are some after market options to help provide some extra comfort in your kayak, such as the Skwoosh Paddling Cushion, however, those are primarily designed to provide cushioning. Because you are experiencing lower back pain, a cushion may not be the solution, or at least not long term.
It is important to remember that we aren't qualified to give medical advice, so you'll want to consult with your doctor any time you're experiencing pain during or after an activity, or beginning any exercise regimen. Kayaking engages your muscles (particularly your core) in a very unique way. Take a look at this Expert Advice article, How to Train for Kayaking, for some exercises that can help strengthen the muscles you use most when kayaking. Additionally, proper paddle technique is very important to being comfortable in a kayak for long periods of time. How to Paddle a Kayak: Basic Paddle Strokes may give you some pointers on things to adjust or to focus on to make your kayaking more comfortable.
Hopefully this helps, thanks!
I wondered about paddling technique as well. Worth checking out...