A gas tank bike frame with a built-in tank can provide an integrated base for a motorized bicycle project. The right choice depends on engine type, rear-frame width, and fit measurements. The CDHPOWER G4-I is best for a 4-stroke build with a 142mm rear width; the 135mm CDHPOWER frame is designed for specified 2-cycle engines. The other options list 3.4L tanks and detailed fit dimensions, so compare those measurements with your bike before choosing.
| Frame | Best for | Key fit detail |
|---|---|---|
| Integrated Bicycle Gas Frame | Builders comparing 2-stroke and 4-stroke use | 44mm bottom bracket; 27.2mm seatpost |
| CDH G4-I, 142mm | 4-stroke builds | 142mm rear width |
| 3.4L Felt Faker Frame | Builders seeking broad listed engine use | 44mm bottom bracket; 27.2mm seatpost |
| CDHPOWER, 135mm | Specified 2-cycle engines | 135mm rear width |
| CDH G4, 195mm | 4-stroke builds needing wider rear spacing | 195mm rear width |
Integrated Bicycle Gas Frame, 3.4L
This black frame is listed with a built-in 3.4L tank and is described as suitable for 2-stroke and 4-stroke engine bikes. Its fit specifications include a 1 1/8-inch headset, 44mm bottom bracket diameter, 27.2mm seatpost, 42mm bottom tube, and 31.8mm seatpost clamp. The listing also gives a 44mm center axle measurement.
Best for: Builders whose bike matches these measurements and who want a frame presented for either 2-stroke or 4-stroke use. It was selected for its stated engine range and detailed sizing. Limitation: The listing says it is without a kickstand, so buyers needing one should plan accordingly.
CDHPOWER G4-I Gas Frame, 142mm
The CDHPOWER G4-I has a built-in 3.4L fuel tank and is designed for 4-stroke engines. It includes a mounting plate and specifies a 142mm rear width. The listed seatpost requirement is 27.2mm, and the headset requirement is 1 1/8 inch. A gas tank cap is included, and the frame requires a 10×1.5mm petcock fuel valve connection.
Best for: A 4-stroke conversion where the bike’s rear width and front-end dimensions match the listing. It stands out for clearly stating the engine type and rear spacing. Limitation: It is not presented as a universal 2-stroke frame, and the petcock connection size needs to match.
3.4L Felt Faker Gas Frame
This frame is listed for 66cc, 80cc, and 100cc motorized bicycle setups and describes compatibility with both 2-stroke and 4-stroke engine bikes. Its specified dimensions include a 1 1/8-inch headset, 44mm bottom bracket, 27.2mm seatpost, 42mm bottom tube, 31.8mm seatpost clamp, and 44mm center axle.
Best for: Builders who want a 3.4L tank and whose frame measurements align with the stated specifications. The combination of listed engine types and detailed dimensions makes it useful to compare with the other options. Limitation: The listing says it is without a kickstand; confirm all measurements before ordering rather than relying only on the engine-size description.
CDHPOWER Gas Frame, 135mm Rear Width
This CDHPOWER frame has a built-in 3.4L tank and is specified for 2-cycle engines, including 48cc, 66cc, and 80cc models. It has a 135mm rear width, a rear disc brake bracket, and a 27.2mm seatpost requirement. The listing describes heavy-duty construction for gas-engine applications and says the frame is suitable for single-speed and multi-speed bikes.
Best for: A 2-cycle project using one of the listed engine sizes and a bike that requires 135mm rear spacing. It is the clearest choice here for those specific engine and width details. Limitation: The listed engine application is narrower than frames described for both 2-stroke and 4-stroke use. Check the required 10×1.5mm switch specification.
CDH G4 Gas Frame, 195mm Rear Width
The CDH G4-II has a built-in 3.4L tank and is intended for 4-stroke engines, with a mounting plate. Its rear width is 195mm. The stated fit requirements are a 27.2mm seatpost and a 1 1/8-inch headset. The listing specifies a 10×1.5mm petcock fuel valve and says a gas tank cap is included.
Best for: A 4-stroke build where a 195mm rear width is required. It was selected as the widest rear-spacing option in this product group. Limitation: Its 195mm measurement differs from the 135mm and 142mm options, so verify the bike’s rear spacing before choosing it.
Buying Guide: How to Choose a Gas Tank Bike Frame
Which engine type does the frame support?
Start with the frame’s stated engine application. Some listings describe use with both 2-stroke and 4-stroke engines, while the CDHPOWER 135mm frame specifies 2-cycle engines and the two G4 frames specify 4-stroke engines. Treat these descriptions as selection guidance, then verify that the frame and mounting arrangement suit your build.
What measurements should you check?
Compare the frame’s headset, seatpost, bottom bracket, tube, and rear-width requirements with your bicycle. A matching engine description does not establish a fit if the dimensions differ. For a frame with a fuel valve requirement, check the listed petcock connection or switch specification as well.
Does rear width matter?
Yes. The products here specify 135mm, 142mm, or 195mm rear width. These measurements are not interchangeable; identify the width needed for the bike before selecting a frame. Also compare brake-related details, such as the listed rear disc brake bracket, against your build requirements.
Is an integrated tank the right choice?
A built-in tank combines the tank and frame in one listed component, and these options specify a 3.4L capacity. Check whether the frame includes the cap, what fuel-valve connection it requires, and whether a kickstand is included when those details matter to your project.
Frequently Asked Questions
What does a gas tank bike frame do?
It provides the bicycle frame structure and, in these products, incorporates a fuel tank for a motorized bicycle build.
Are all five frames compatible with 4-stroke engines?
No. The G4-I and G4 listings specify 4-stroke use. The first and third products describe both 2-stroke and 4-stroke use, while the 135mm CDHPOWER frame specifies 2-cycle engines.
Do these frames all have the same rear width?
No. The listed rear widths include 135mm, 142mm, and 195mm. Choose based on the bicycle’s required rear spacing.
What fuel valve size should I check?
The G4 listings specify a 10×1.5mm petcock fuel valve. The 135mm CDHPOWER frame lists a 10×1.5mm switch requirement. Confirm the connection details for the specific frame before purchase.