SirLightalot wrote:Had a friendly discussion with and old friend who said that Polyprops are just as warm as Merino. I had too agree, and thought about this a bit more while riding, and thought Poly props are only $20 and Merinos' $120, until I realised the big difference.

Your body heat regulates alot better with Merino, where as Poly props, well my experience is you can overheat, say on a long climb, and I don't think they hold heat when wet.

when dry weight polypro is warmer for it's weight. it also gets smelly quickly, gets cold when wet and is great to start fires with.

the main difference is where merino regulates temperature and manages moisture. it's much better in this regard as it's a natural fibre rather than some old plastic bags with some rainbow stripes on them.

merino is great in all conditions - I use it as a single layer during summer for MTB, running and at work. In winter it goes on under my thermal jacket to keep me warm and dry. in autumn and spring a lightweight merino base layer underneath your normal riding top can be perfect.