Originally Posted by
pwdeegan
1. proper rain gear is not just waterproof, but designed for cyclists. among the best (if not the best) is Showers Pass gear (mentioned above). Pick something for your temperature range. You can still overheat, but less so than other jackets/covers not optimized for cycling. If you really overheat, try just slowing down a bit, after all it helps visibility...
Yeah, but the OP is right. Different rain gear may or may not make a slight difference, but it's not magic. I own the premium Shower's Pass stuff and it's no good above 60 degrees, even with the arm vents open, the jacket zipper slightly open, etc etc.
You have several factors -
1. You're exercising and your body is producing a lot of heat. Even if you slow down some, it's still very significant.
2. Your rain gear covers your entire torso or body with an insulating layer.
3. Your rain gear is windproof - you lose almost all the cooling benefits of riding into the wind.