Need Help Mounting Honda GS 190 Engine on a PhatMOTO Bike

Comprehensive Guide to Modifying a GS190 Engine for Phatmoto Frame

Hello everyone! I’ve embarked on a project earlier last week to enhance my bike by fitting a GS190 engine and making several modifications for better performance and fit. The journey involved meticulous adjustments and custom fittings, reaching a satisfying top speed of 48 MPH. Below is a step-by-step guide detailing each modification I made. If you're considering a similar project, or need some tips on these kinds of modifications, feel free to reach out!

**Modification Steps:**

1. **Initial Assessment and Dry Fit:**
- Start by dry-fitting the engine to understand the initial placement and identify any major issues with component fitment.

2. **Removal of Incompatible Parts:**
- Remove the gas tank and air filter which did not fit with the new engine configuration.

3. **Carburetor Upgrade:**
- Replace the non-fitting air filter with a Racing carburetor to ensure adequate airflow and fitment.

4. **Engine Repositioning:**
- Adjust the engine slightly to the right to align the torque converter with the chain and rear sprocket.

5. **Frame Modifications:**
- Drill new holes on the left side of the frame for the engine mounts and file near the oil cap to create necessary clearance.

6. **Torque Converter Adjustments:**
- Remove and modify the torque converter’s sprocket, grind down specific areas, and re-angle it for frame clearance and drill new holes on mount.

7. **Valve Cover Adjustments:**
- Modify and bend the valve covers for clearance; crucial to do this off the bike and avoid adjustments when mounted. Can also file down rear valve screw 1/8th to fit better.

8. **Flywheel and Pedal Modifications:**
- Cut and grind the flywheel and modify the pedal post with a blowtorch to ensure clearance without compromising functionality.

9. **Silencer Muffler Installation:**
- Install a silencer muffler using copper piping and bracing, attaching it securely with self-tapping screws for reduced noise.

Ongoing Adjustments:
I'm still in the process of fine-tuning the carburetor and adjusting the spring tension to squeeze out a bit more top speed. However, with the current setup, I consistently achieve 48 MPH with the governor disengaged.

This project was both challenging and rewarding, showcasing that modifying a bike requires not just mechanical skills but also a bit of creativity and persistence. If anyone needs advice or has questions about similar modifications, feel free to ask. I'm here to help and share more about my experiences!


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