I want to buy a road bike. My current bike is a Trek 7.2 hyrbid, and I've never ridden a road bike before today.

I went to two different bike stores, and at least on paper, a cannondale Synapse 6 is the ideal bike, so I went to two stores that sold cannondale to talk to the salesmen. What I found odd is they had way different ideas on what size I should get. The first store recommended 61cm, the second store recommended 56cm.

I'm 6'2 1/2", so I'm a tall guy, so I would think 56 cm would be way too small. The dealer that recommended a 61cm frame didn't have the bike assembled, as it just arrived. I did ride a 56cm frame and the bars seemed too low. If that was the only problem I don't mind getting a longer stem. They didn't have a 58 mm in stock to try to ride.

I'm just wondering what size seems best to you. I fully realize that having never meet me, you can't tell me exactly what fit I should be, but I just found it odd that their size recommendations would be so much different.

Another problem is I've never been on a road bike before today, so I don't even have an idea on how it should feel when properly fitted. I know it did feel faster and more efficient than my hybrid, but it didn't seem like the 56cm was relaxed at all. It felt too aggressive. I just don't want to spend 1400 on a bike only to realize the fit is off.

I do plan on renting a giant defy 5 next weekend, and putting about 30-40 miles on it, so at least I'll have a bit of experience on a road bike and have something to compare it to. (the defy 5 is the only road bike model they rent)

You're on the right track. You'll need at least a 58, probably the 61. They salesman at the shop recommending the 56 is likely either clueless or has slippery ethics.

I'd expect 58 or 61 too, depending on how you're proportioned. I'm almost exactly your height and ride a 61cm Roubaix.

56's in general feel like little clown bikes to me.

56 might work. Proportions matter and the goal of riding.
A 56 will most likely be extremely racey and aggressive soif you want that...
Otherwise a 58 might be a better choice

Thanks for the responses. I'm going to try out the 61 when it is built, as well as a 58 at the same time to compare the two, as well as a few other bikes and dealers.

The second bike store (recommending me the 56) has a bad reputation, so I would have avoided it, but when the first one didn't have a bike ready in my size, I thought I would check them out since they were close by.

And yeah, I realize that for a racey bike, perhaps a 56 could work, if I wanted an aggressive bike, but given that I was looking at relaxed geometry bikes, he should have know that I didn't want that (plus I mentioned I wanted relaxed geometry).

Many people CAN fit two or three different size of frames, and can make it work with stems and spacers.

I typically prefer the biggest frame I can get on; but I like more "classic" geometry. Some racers ride the smallest frame they can get on, so they can run ridiculous handlebar drops, and have a lighter/stiffer frame.

But don't let a shop solve their inventory problem on your bike fit.

61 Tell0004. I'm 6'1" with long legs and arms have owned a 61 and it was a good fit. I am on a 58 Roubaix and only reason why I don't ride a 61 Roubaix and I could easily is because the Roubaix already has the tallest head tube in the industry for its size. I ride it with a 130mm stem and have had a 140mm stem on it as well. To me, sizing down is a big mistake. But many choose this path and what makes the world go around.
Btw, if you are unfamiliar with road bikes, it will take you a season of purposeful riding to embrace the position. What will feel stretched out to you initially may in fact feel cramped as you learn to stretch out and use your power.
Have fun.

A general guide for frame sizes CLICK HERE