What It Takes To Build a Bike Under 10kg

Building a bike under 10kg is like trying to create a masterpiece while balancing on a tightrope.

You need precision, patience, and a little madness. I’ve been down this road before, and let me tell you—it’s not for the faint of heart.

There’s no easy way to do it. But for those who crave the thrill of the chase, who want to be lighter on their feet while riding through the city or tackling long rides without carrying an anchor on their back, it’s all worth it.

So, let’s get one thing straight—if you want a bike that feels like a feather but looks like something out of a vintage dream, it’s going to be a dance between lightness and sacrifice. You’ve got to pick your battles.

1. The Frame—A Steel Horse That Weighs Less

Steel? Yeah, it has that classic look, but you’re not fooling anyone if you think it’s light. You’re better off finding a frame with the right tube dimensions (think vintage vibes) that won’t make you feel like you’re pushing a tank.

If you still insist on steel, be prepared for a heavier price tag for the lightweight versions. But if you’re in it for the aesthetics and the feel of something timeless, the weight won’t be your best friend.

Then, of course, there’s titanium. The golden child of lightweight material. But at what cost?

You might find a deal on eBay, but buying custom titanium frames from unknown sellers is like gambling.

Sometimes you win big, sometimes you end up with something that doesn’t even resemble a bike frame. But if you get it right, it’s magic—flexible, strong, and light as hell.

2. Hydraulic Disc Brakes—Beauty with Power

You want hydraulic disc brakes. I get it. You’re imagining yourself in the rain, zooming down the road, stopping on a dime. But here’s the truth: you’re going to pay for that power.

Disc brakes are heavier, and when you pair them with a steel frame, the weight stacks up. It’s not impossible to get them under 10kg, but you’ll have to make sacrifices elsewhere.

A lighter frame might help, but there’s always a trade-off.

3. Carbon vs. Steel—Can’t Have Both?

You’ve got to ask yourself: “Do I want something that screams ‘modern performance,’ or do I want a classic ride with a little soul?” Carbon frames are the answer for those chasing pure performance and lightness, but they’re cold.

They lack the character of steel.

If you’re building a vintage-looking bike, carbon’s not going to play nice. But if you just want to hit that magical 10kg, it’s hard to argue with carbon.

4. Custom Builds—More Than Just a Frame

You’re looking to customize. Good choice. But let me tell you, building a bike is not just about the frame. Wheels, seat posts, handlebars—every piece has to be lightweight without compromising on strength.

Carbon rims are the key to cutting down weight, but at what price? The same goes for the cockpit and seat. You can get a light saddle, but you’ll need to sell your soul for it. Don’t forget about your drivetrain. Go for a 1x setup to keep it simple and light.

5. The Fit—No One Wants to Ride a Torture Device

You’re short, and you’ve got back issues. This is where a custom fit becomes your secret weapon.

Get a proper fitting before you even think about buying parts. A custom frame might be your best bet if off-the-shelf options aren’t cutting it.

You want a bike that feels like an extension of yourself, not a medieval torture device. So, get a proper fitting, and find a bike that works with your body, not against it.

6. The Budget—Can You Afford to Lose Weight?

It all comes down to money, doesn’t it? If you want something truly lightweight, you’ll need to dig deep into your pockets. A full carbon build will get you there, but it’s going to hurt your wallet.

If you’re on a budget, aluminum is your best friend. It’s not the lightest, but it’s a hell of a lot cheaper than titanium or carbon.

You can still make it work with a mix of lighter components, but don’t expect the lightest setup unless you’re ready to pay for it.

7. Where to Buy—You Might Want to Shop Around

eBay might seem like a good place for custom frames, but if you’re not buying from a trusted source, you might end up with a lemon.

Check out established brands or smaller companies offering custom builds. Look for lightweight components, but don’t skimp on quality.

If you’re going for something vintage, there are a ton of boutique brands out there that will make you a frame that fits your exact needs.

Summary Table:

Component	Material Choices	Weight Impact	Cost Impact
Frame	Steel, Titanium, Carbon	High (Steel), Low (Titanium, Carbon)	High (Titanium, Carbon), Moderate (Steel)
Brakes	Hydraulic Disc	Heavy	High
Wheels	Carbon	Light	High
Drivetrain	1x Setup	Light	Moderate
Fit	Custom Fit	Neutral	Variable
Material Choice	Carbon, Titanium, Steel	Carbon: Light, Steel: Heavy	Carbon: Expensive, Steel: Cheaper
Budget	Mix Components	Balance Weight & Cost	Significant Investment Needed

Conclusion

Here’s the deal: Building a bike under 10kg isn’t just about parts—it’s about striking a balance.

You’ll chase that lightweight dream and find that it’s never quite perfect.

You’ll make compromises, give up on the pure vintage look for a performance edge, or bleed money for a frame that sings your style.

But when it’s all said and done, that bike will be yours—unique, fast, and a reminder that you’re willing to put in the work.

Just don’t expect to leave without a scar.

You can have your cake, but you might have to give up dessert.