How I Turned a Rs 80,000 United into a 200cc Monster
What started as a budget commuter bike turned into my passion project. Over six months, I transformed a basic United US 100 into a legitimate performance machine that leaves 150cc bikes in the dust. Here's exactly how I did it - with full cost breakdown.
Phase 1: Engine Swap (Budget: Rs 35,000)
The original 100cc engine had to go. I sourced a 200cc GY6 engine from a Chinese ATV - yes, you read that right. These engines are bulletproof and make excellent transplant candidates.
What I Needed:
- 200cc GY6 engine (used, but in good condition) - Rs 22,000
- Custom engine mounts fabrication - Rs 4,000
- Modified exhaust system - Rs 3,500
- New carburetor (24mm) - Rs 2,800
- Wiring harness modifications - Rs 2,700
The Installation Process
This wasn't plug-and-play. I spent countless hours at my trusted mechanic's workshop (shoutout to Ustad Azeem in Shahdara!). The frame needed custom mounting brackets welded, which took three attempts to get right.
Pro tip: The GY6 engine is wider than the stock engine. We had to grind down some frame sections and relocate the foot pegs slightly. Not ideal, but necessary.
Phase 2: Transmission & Drivetrain (Budget: Rs 18,000)
More power means you need better components to handle it. The stock transmission would've exploded within weeks.
Upgrades:
- Heavy-duty clutch plates (set of 5) - Rs 3,200
- Reinforced clutch springs - Rs 1,100
- 520 heavy-duty chain and sprocket set - Rs 6,500
- Modified gearbox (4-speed to 5-speed conversion) - Rs 7,200
The 5-speed gearbox was the game-changer. It came from a crashed Honda CG125 that I found in Brandreth Road. Cost a fortune but worth every rupee.
Phase 3: Suspension & Brakes (Budget: Rs 25,000)
You can't go fast if you can't stop. And the stock suspension was laughably inadequate for the new power.
Front End:
- Inverted forks from Honda CB150F (used) - Rs 12,000
- Custom triple clamp fabrication - Rs 3,500
- Hydraulic disc brake upgrade (260mm rotor) - Rs 5,800
Rear End:
- Gas-charged shock absorbers (pair) - Rs 3,700
Finding those CB150F forks was pure luck. A friend crashed his bike, and I bought the front end for cheap. They needed new seals (Rs 800), but otherwise perfect.
The Final Result
Total Investment: Rs 98,500 (including the original bike at Rs 80,000)
Performance Numbers:
- Top speed: 120 km/h (GPS verified)
- 0-60 km/h: 4.2 seconds
- Fuel average: 35-40 km/liter (worth it!)
- Power-to-weight ratio: Better than most 150cc bikes
What It's Like to Ride
This bike is an absolute weapon. The power delivery is brutal - twist the throttle and it lunges forward. The handling is sharp thanks to the upgraded suspension. Braking is confident and inspiring.
But it's not perfect. The riding position is aggressive (not great for long distances), and it vibrates like crazy above 80 km/h. Fuel economy took a hit, obviously. And you NEED to maintain it religiously - this much power stresses every component.
Should You Do This?
Only if:
- You're passionate about bikes and mechanical work
- You have the budget and time (this took 6 months)
- You understand this voids all warranties
- You're prepared for constant maintenance
- You can handle police scrutiny
If you just want reliable transportation, buy a stock bike. But if you want to learn, experiment, and build something unique - go for it! The satisfaction of riding something you built is unmatched.
