Road bikes are all about speed, and in order to be faster, they need to be lighter. Manufacturers significantly reduced weight by introducing carbon fiber, but the weight ratio between the individual parts remained almost unchanged.
The frame is the heaviest part of the bicycle, followed by the wheels. However, if both parts are made from carbon fiber, it’s common that the frame weighs less than a set of wheels. The third heaviest part is a crankset, with disc brakes and shifters coming fourth and fifth.
In this article, I will present you with the ultimate ranking of every significant part of a road bike. I will also cover how the rankings change if you have carbon fiber parts and the most inexpensive way to reduce the overall weight.
You can reduce the weight of the bike by using carbon parts. You can find them by clicking here.
Heaviest and lightest bike parts
Twenty parts make up the whole bike. Most of them are visible, but some are hidden inside the frame. There is also a ton (not a literal ton) of minor parts such as screws, bearings, and cables that I didn’t include in my ranking as they don’t influence overall weight that much.
The table below includes aluminum parts, which are the most used by cycling beginners. Later on, we’ll check how much carbon parts weigh and how the ranking changes, but we’ll stick with aluminum for now.
Every parts’ weight is based on specifications provided by manufacturers. I checked the ten most popular models from different brands and calculated the average weight presented in the table below.
It is important to know that some parts already include other parts. For example, wheelsets’ weight already includes the weight of hubs. However, you can replace them. Therefore, they are included in the table as a stand-alone part.
*The only two mutually exclusive parts are disc and rim brakes. It’s up to the rider to decide which to use, so I’ve included both.
| Rank | Bike Part | Average Weight | Weight Range |
|---|---|---|---|
| 1 | Frame (with forks) | 1809 g / 3.98 lbs | 1450-2300 g / 3.20-5.07 lbs |
| 2 | Wheelset | 1658 g / 3.66 lbs | 1480-2015 g / 3.26-4.44 lbs |
| 3 | Crankset | 769 g / 1.69 lb | 618-974 g / 1.36-2.15 lbs |
| 4 | Disc brakes | 526 g / 1.16 lb | 421-670 g / 0.93-1.48 lb |
| 5 | Shifters | 355 g / 0.78 lb | 280 – 554 g / 0.62-1.22 lb |
| 6 | Rim brakes | 323 g / 0.71 lb | 262-379 g / 0.58-0.84 lb |
| 7 | Handlebar | 293 g / 0.65 lb | 253-375 g / 0.55-0.83 lb |
| 8 | Seatpost | 264 g / 0.58 lb | 172-310 g / 0.38-0.68 lb |
| 9 | Chain | 261 g / 0.57 lb | 247-287 g / 0.54-0.63 lb |
| 10 | Cassette (11-speed) | 254 g / 0.56 lb | 135-394 g / 0.30-0.87 lb |
| 11 | Hub (rear) | 247 g / 0.54 lb | 183-361 g / 0.40-0.80 lb |
| 12 | Saddle | 247 g / 0.54 lb | 205-349 g / 0.45-0.77 lb |
| 13 | Derailleur (rear) | 221 g / 0.49 lb | 158-284 g / 0.35-0.63 lb |
| 14 | Pedals | 220 g / 0.49 lb | 95-320 g / 0.21-0.71 lb |
| 15 | Stem | 142 g / 0.31 lb | 81-240 g / 0.18-0.53 lb |
| 16 | Hub (front) | 135 g / 0.30 lb | 87-225 g / 0.19-0.37 lb |
| 17 | Headset | 111 g / 0.24 lb | 84-170 g / 0.19-0.37 lb |
| 18 | Bottom bracket | 95 g / 0.21 lb | 76-123 g / 0.17-0.27 lb |
| 19 | Derailleur (front) | 94 g / 0.21 lb | 70-132 g / 0.15-0.29 lb |
| 20 | Thru-axle | 50 g / 0.11 lb | 30-78 g / 0.07-0.17 lb |
| 21 | Seat clamp | 25 g / 0.06 lb | 12-40 g / 0.03-0.09 lb |
Frame and wheelset are by far the heaviest parts of the bike, making up almost 50 % of the overall weight. Consequentially manufacturers spend a lot of time and resources to make them as light as possible.
Cyclists commonly upgrade wheels to make bikes lighter and more aerodynamic. On the other hand, a frame is rarely replaced, as it represents the heart of the bike, and replacing it would mean you are basically getting a new bike.
Let’s stop at the brakes for a few moments (pun intended). There is a real war going on over whether disc or rim brakes are better. I won’t choose sides but rather look at the debate in terms of weight.
Disc brakes are heavier; there is no denying it. With bikes becoming lighter, there is more wiggle room to equip a bike with discs, and I’m sure that at one point, almost every bike will have disc brakes.
However, if you’re obsessed with your bike weight, then choose rim brakes. I recommend something like Shimano 105 or Shimano Ultegra that you can find on Amazon. Just there, you can save 200 grams (0.44 lb) easily, which is about 2.5 percent of overall bike weight.
The lower down the rankings you go, the less chance you have of reducing weight. The weight range becomes smaller, and even if the heaviest model is 3x heavier than the lightest, we’re still talking about only a few grams of weight reduction.
How do carbon parts change the rankings?
Carbon fiber made its first steps into the world of cycling at the end of the last millennium. Cyclists soon realized that it is superior to aluminum as it is much lighter and faster.
In recent years bikes and bike parts used by professionals are almost exclusively made of carbon fiber. The trend has also taken over recreational levels. Everybody wants to have a carbon bike, but the price is too high for many.
If you’re prepared to spend serious money on your bike and its part, then carbon is the way to go. Components are much lighter than aluminum, which reflects in changes to our ranking.
The table below shows only carbon parts. Other parts which do not have a carbon version stayed in the same order but were moved higher due to the lower rank of carbon parts.
| Rank (prev.) | Bike Part | Average Weight | Avg. Weight Reduction |
|---|---|---|---|
| 1 (2) | Wheelset | 1522 g / 3.36 lbs | 136 g / 0.30 lb |
| 2 (1) | Frame (with forks) | 1460 g / 3.22 lbs | 349 g / 0.77 lb |
| … | |||
| 12 (7) | Handlebar | 209 g / 0.46 lb | 84 g / 0.19 lb |
| 13 (8) | Seatpost | 176 g / 0.39 lb | 89 g / 0.20 lb |
| … | |||
| 16 (12) | Saddle | 132 g / 0.29 lb | 115 g / 0.25 lb |
Replacing an aluminum frame with carbon will reduce the weight the most, but as mentioned previously, you’re pretty much buying a new bike at that point.
The information might be more useful when you’re actually buying a new bike. If you choose a carbon frame rather than aluminum, you will reduce the overall weight by 349 g (0.77 lb).
Adding a few other carbon components will reduce the weight even further. Dropping about a kilo (2.20 lbs) is totally achievable, but it will be expensive.
Carbon parts are not only lighter than aluminum but are also stiffer and better at damping vibration. Most of us won’t be buying carbon saddle to save 115 grams but to give us a smoother ride. I actually wrote an article about whether it’s worth upgrading your saddle with a carbon model so check out what I found out.
In fact, a recreational cyclist will buy most carbon bike parts because it will improve his ride rather than make him faster. Only frame and wheels are typically purchased to reduce the weight, as the difference to the aluminum parts is the greatest.
The cheapest way to reduce weight
Reducing bike weight is an expensive project, especially if you’re doing it on a bike that you already own. It’s much cheaper getting carbon parts when you’re buying a new bike, as you don’t have to pay for aluminum first and then later upgrade to carbon.
Most bike retailers offer the option to pay extra for carbon parts when buying a new bike.
I have looked at the price differences between aluminum and carbon parts. I then divided this number by the average weight reduction and got the answer to the question of which bike part is the most cost-effective to reduce weight.
| Bike Part | Cost per one gram reduction |
|---|---|
| Frame | 7.34 $/g |
| Wheelset | 8.06 $/g |
| Handlebar | 3.42 $/g |
| Seatpost | 1.81 $/g |
| Saddle | 4.09 $/g |
Seatpost is a clear winner, as cost per one gram (about 0.035 oz) reduction is almost twice less than the next cheapest part.
Handlebar takes second place, with just shy of $3.5 per gram of lost weight. With about 60 cents per gram more, the third place goes to saddle.
All three parts play an important role in the comfort of your ride. This is especially true for the seatpost, as it absorbs vibrations that would otherwise be transmitted directly to your body.
Weight reduction has its limits. Spending $500 on a new seatpost doesn’t mean it will be 276 grams lighter than aluminum, as that is physically not possible. The same goes for the other two parts as well.
The frame and the wheels are in a completely different price category. I was surprised to learn that weight reduction with wheels is more expensive than with a frame. But then again, when you buy wheels, you are also paying the price of aerodynamic improvements.
