Instruction: Output yes if the supporting document can answer the given question. Otherwise, output no.

Input:
Question: Will this fit on a 48cm road bike frame?
Document: This rack does not really fit old road bike frames like the trek 1000 from the late 90's. Adapters were needed as well as a lot of swings with a hammer. Once I got it attached it worked OK.  Buy a different rack if you have an old road bike frame, otherwise it's a good rack.
The bottom brackets are too narrow to be bent to fit on the outside of the frame, the bike rack wants to go to the inside of the frame where it would interfere with the rear cassette. Even if you manage to flex it wide enough to fit on the outside of the frame then the rack itself is too short for the brackets of the rack to reach the eyelets in the seat stays.Might fit mountain bikes or cruisers but definitely do not buy if you have a road bike frame.
I have an 1980's road bike with a 25 inch frame so it's a big bike. I finally jerry rigged this to work but it took a trip to the hardware store to find an extra bolt, a call to the company and a ton of research. All said and done, it seems like it'll do what I wanted it to do; hold a storage box. However, saying this will "work on 97% of bikes" is a very broad definition of "working".
This rack is really sturdy. It is however not "oversized" but still a good product for the cost. It took a little time to figure out the installation (no instructions) but is actually a good system. It will fit about any size bike. I might add that I'm a mechanic. The trick is the mounting brackets to the frame are meant to be bent to fit the particular bike size. Once that became clear, it was easy to install.
I researched rear bike racks from the cheapest to the most expensive and settled on two of these Ecoracks at $30 each to add to our two 1975 vintage ten-speed bikes. My concern was that the racks would not fit, especially on my bike which has an very tall frame. These racks are classy in appearance, will support 55 pounds (more than others in this price range) and the sellers claim that the rack will fit 97% of frames is probably true.
High quality construction with versatility to fit most any bicycle frame at remarkably reasonable price. As good or better than more expensive brand.
That wasn't an issue in my case but is something to be cautious of.Overall, this is a good rack that will fit a standard frame with a minimum of fuss or engineering effort, and comes at a very reasonable cost. Bolts and nuts are cheap, but do plan on buying them if you get this.There are several adapters included for more unusual installations. As I didn't need any of them, I can't speak to their quality or usefulness.
I purchased this product due to the description "Fits 97 percent of all mountain and hybrid/road bike frames". I guess I was one the the unlucky 3%....
Silver looks good with the frame on the bike too.
I installed this on my Cannondale Quick hybrid. Installation was straightforward and the rack is sturdy and fits securely.Pros:--The rack is easy to install on a standard modern bike frame, and could be done even by someone who doesn't have a great deal of experience at bicycle maintenance. Some tools (an Allen wrench certainly, vise grips and/or end wrench helpful) will be required.--The rack is very sturdy.
Answer: yes