Hey guys, Just a quick question from a new rider. When out and about on a 10-15 mile ride I start to feel some aches and pains in my upper back near my neck. Would this be down to seat height or handles? It's nothing unbearable but it does kind of make me stiff for a while riding. And just to note it can't be an age thing (I hope) as I'm not too old! Cheers.