I've been searching for a new bike ever since my Cannondale was stolen about a month ago. I like the loos of this Ridley but I don't understand the sizing options performance is offering. What is "small" or "large" , and how does that compare to my 58cm Cannondale (which was just barely too big for me)?

Product: Ridley Fenix AL2 Tiagra 7005 Road Bike - 2014 Performance Exclusive

I am assuming, based on the price range, that you are comparing it to a CAAD. With that being said, I would think that you would be comparing it to a Large Ridley Fenix frame.
I would go try one out though since you said that your old CAAD was slightly too large. Sometimes the numbers given are not actual. My old bike was a 61cm but it was actually 58.5. Nothing beats going and sitting on the bike and riding it though.
I recently looked at the Fenix in an XL. It is an awesome bike and Performance has great deals on them.

Compare stack and reach. That is how a bike should be sized for you. If you can't find stack and reach for the two bikes you want to compare, use horizontal (effective) top tube length and head tube length. That works pretty well too. More simply, many bike makers use M for a size 54 and each size on bith sides of that differs by two cm. That is not universal however. But even if Ridley used numerical sizes, you would want to confirm the similarity to your old frame of the stack and reach or top tube and head tube.

I'd agree with Robert. Try to compare stack and reach along with effective top tube. I had a small Ridley that I thought would be perfect given the numbers (and I really wanted a 140mm head tube), but in the end the top tube was simply too long and I had a hard time getting setback, and good stem fit. I loved the Ridley but just could not get it to fit the way I wanted. Should have gotten an XS.

Test ride would be nice for the basics of course, just understand that if you buy it they can make basic changes like stem length.

I would like to echo the advice that you might go find a Ridley dealer and size out this bike. I did so before buying my Ridley X-Fire (which is a 52 cm). Even this way, I have had to add a slightly longer stem to lengthen the top tube to my needs. As a means of comparison, my road bike is a 54 cm Trek. I believe that the frame size measurements for Ridleys may be available with a google search. I have heard that the Ridley sizing tends to run a bit large anyway, so, getting to a dealer could be the best way to tell what will work for you

This is probably a ridiculous question, but why is there such a large price difference between performance and this website?

2014 Ridley Fenix AL2 Tiagra 7005 Road Bike 2014 Ridley Fenix AL2 Tiagra 7005 Road Bike [Fenix AL2 Tiagra 7005 Road Bike] - $499.00

If the 58cm Cannondale was a little big for you, the Medium in Ridley should work for you.

I'd bet that website is rubbish. A new, sub-$500 Ridley? Come on...

I'm 5-9 with a 35-inch inseam and I ride a large Ridley Orion. I had to have the cockpit adjusted slightly but other than that, it's a great fit and a comfortable ride. I did get fit at my LBS where I bought it though. For comparison, I'm a 56 in a Specialized Tarmac (the Ridley was more bike for the money :-D ).

Ridleys have weird sizing, so as others have said, check the ETT and stack and reach carefully. I normally ride a 54 and got a size small Excalibur frame.

I have no problem buying a bike online. However, you must be more than very careful when buying a bike from Indonesia.There is a massive amount of fraud on bike sites there. I highly doubt that the site above is legit. I am not saying that Performance is the least expensive place in the world but it is not likely that they will be that under priced. If it it looks too good to be true..... Since you asked the question, you probably already know how it ends.

There is also the matter of a USA warranty (if that is what you require). For sure the bike from Indonesia won't come with one. That alone could explain the price difference, but I agree that in all likelihood there is even more to it than that.

At least Performance will adjust the bike to fit you and has free lifetime adjustments. A friend purchased a Ridley Fenix from Performance about six weeks ago and has no complaints.

I picked up a Fenix too after 3 hours of test riding. I'm extremely happy with my purchase. I just wish grad school would let me go ride more.

I have recently purchased a Fuji tread 1.1 (cx) which generally run smaller, it was a 56, went back for a Ridley fenix and sized out with a 54......

The M in ridley size chart has an effective top tube of 56, while it's usually 54 for other brands.

Ridley frames fit small. I ride a 54 Cervelo, and comparing stack and reach the Ridley size small was too big in the Helium frame. So I got a XS and put a 10mm longer stem for the same fit. The stem is still slammed on both. This is weird since I am 5' 7" with normal proportions, riding the smallest frame that Ridley makes.

$1700? How about this
Ridley Fenix Force 22 Featured Road Bike - 2015 | Competitive Cyclist

ya'll are posting in a zombie thread.