Before you buy a bicycle frame, you have to decide what you're building. These four frames are aimed at very different projects: one suits a classic restoration, one is built for off-road use, one is a new frame, and one is a modern frameset for mixed surfaces. The table below shows the listed prices, and the product notes explain what each frame includes and where it falls short.
Quick take
A wide price range separates these four frames, so the decision is mostly about which build style you want. The table below shows the listed prices, and the notes explain the strengths and limitations of each frame.
Side-by-side listed prices
| Frame | Listed price | Price bar | Condition | Frame material |
| Niner SIR 9 V1 Solid Gold | USD 449.95 | | Used | Reynolds 853 steel |
| Vintage Windsor Carrera 59cm | USD 219.99 | | Used | Lugged steel |
| Micargi Puma Stretch 26-inch | USD 250.99 | | New | Steel |
| BXT Gravel Frameset 700C | USD 454.35 | | New | T1000 carbon |
Decision matrix
| Frame | Wheel size | Best build type |
| Niner SIR 9 V1 | 29-inch | Single-speed mountain bike |
| Vintage Windsor Carrera | 27-inch | Road or racing bike |
| Micargi Puma Stretch | 26-inch | Beach cruiser |
| BXT Gravel Frameset | 700C | Gravel bike with disc brakes |
Frame-by-frame notes
Niner SIR 9 V1 Solid Gold (USD 449.95)
If your build is a 29-inch single-speed mountain bike, this Niner SIR 9 V1 frame is a steel foundation with Reynolds 853 tubing. The size medium frame includes a Bio-Centric bottom bracket shell insert set, and the maximum tire clearance is 29 x 2.4 inches. The frame weight is about 4.87 pounds. The trade-off is condition: this is a used frame from 2010, and you will need to source compatible parts for the 135mm rear spacing. At $449.95, it sits near the top of the price range, so only pick it if the singlespeed geometry suits you.
Vintage Windsor Carrera Road Bike Frame (USD 219.99)
For a vintage road or racing project, this Windsor Carrera frame from the 1970s is the lowest-priced frame in this group at $219.99. The lugged steel frame has a matching steel fork with a 1-inch threaded steerer, and SunTour GT rear dropouts with axle adjuster screws are included. It is sized around 59cm seat tube center-to-top and designed for 27-inch wheels with side-pull brakes. The limitation is that this is a used frame with a 120mm rear spacing, so modern hubs will require an adapter or cold-setting, and the orange finish will show patina. If you are comfortable with vintage standards, it is a solid starting point.
Micargi Puma Stretch Bike Frame (USD 250.99)
The Micargi Puma is a new 26-inch steel stretch beach cruiser frame, so you do not have to worry about previous wear. The "stretch" geometry gives the bike a long, relaxed profile, and a chainguard is included. The head tube is 5-1/2 inches with a 1-inch fork tube inner diameter, and the seat post tube inner diameter is 1-1/8 inches. At $250.99, it is the middle price point here. The limitation is that the frame is designed specifically for a stretch cruiser layout, so it will not fit like a standard diamond frame for other riding styles, and you will need to match the fork and wheels to the specified dimensions.
BXT Gravel Bike Frameset (USD 454.35)
The BXT gravel frameset is the only carbon option in this comparison, and it carries the highest listed price at $454.35. Made from T1000 carbon, it has internal routing and disc-brake mounts, and it fits 700C wheels. The frame size is 54cm, and the bottom bracket fit is screw-in BSA 68mm. If you are planning a modern gravel bike, this frameset gives you the main structure. The limitation is that you need to pair it with compatible components in these sizes: BSA 68mm bottom bracket, 31.8mm seat clamp, 27.2mm seat post, and a 52mm headset.
Final recommendation by use case
Choose the Vintage Windsor Carrera Road Bike Frame for a classic restoration. Choose the Niner SIR 9 V1 for an off-road build. Choose the Micargi Puma Stretch Bike Frame for a relaxed custom cruiser. Choose the BXT Gravel Bike Frameset for a modern all-road build.
