I read a post the other day written by a good friend on bike weights and how important that is or is not, depending on how you look at things. I have struggled with this as well and debated with myself on how much bike weight really matters in the grand scheme of things. And, after all this time, I have come to a conclusion.
Pretty decisive, eh? Let me take them one at a time, hmmmm?
Yes: It matters a great deal. A heavy bike is simply more weight to accelerate, stop, turn, and flick around. Mtn bike riding is all about all of these things repeated over and over and over and a lighter bike is better at all of them. Physics? Dunno. But after riding quite a few bikes over the last few years, nearly all of them 29ers, I can only remember one time when lighter was not better and that issue only applied to a narrow section of the ride experience. This applies especially to wheels. Light wheels are pretty boss on a 29er. In fact, I had an engineer for a big bike company tell me that "cheap 29ers suck" as the wheel weight gets ponderous.
No: It is largely irrelevant. A heavy bike will get you there with only a little bit more effort in nearly the same time and likely do it for a lot less money. Lightness costs a lot these days...well, it always did really and that is not likely to change. The sky is just as blue, the air just as sweet on a heavier bike, and there is no pretense or keeping up with the joneses in the gram wars. Want a lighter bundle to get up that hill with? Lose some weight, fatty. What is cheaper...losing 5 pounds off the middle or losing 5 pounds off the bike? It is the rider that makes the real difference.
Maybe: If light means weak or fragile, that is bad. But heavy does not mean strong either. If you are in no hurry and there are no Strava aspirations in your plans, then a heavier bike is no biggie. Who cares if you take a couple of minutes more to get around the trail? But if your buddies are a pack of rippers, then you better be a beast to be a contender on a heavier bike. I have both seen it done AND had my butt handed to me by stronger riders on a porker scooter. If light means overextending your wallet to the point of stress about it, then be content, work on you first and let that bike do for now. If a bike is more of a tool then pegasus to you, then the heavier bike is likely more practical. And so on.
So between ridiculously light and unbelievably heavy lies a wide range of bikes. I have never been one to drill holes in my crank arms (yes, I have seen that done too) and ride unpadded carbon saddles, etc. At some point, the scale of justice tips away from good sense and the money spent to drop those last few ounces is foolishness. Where is that tipping point? When the bike stops being reliable, strong, practical for the purposes it is intended for, and fun to ride.
Fun, after all, is why we do this. Sure some folks do it for a living and maybe they are not having fun at the same time, but that is such a small minority that it is not even on the radar. Bikes are all kinds of things...practical, efficient, affordable to own, providing great exercise and contributing to our well being. But above all other things they are fun to ride.
And I have more fun on a lighter bike, more often as not.