what size road bike?

par said:

What size (approximately) road bike would you guys recommend to someone 5'6". I am looking to get a beginner road bike but want to get the ride height. And from what to what am i measuring this height according to? Crank to seat?

The first most important spec. is the top tube length, the second is the "standover height". Standover height just needs to be adequate so, in the shoes you'll be riding in, you have an inch or two between your crotch and the top tube when you straddle the bike. Assuming you have at least some clearance with the standover, the actual amount is not as important as the top tube length.

Most "frame size" numbers are based on the seat tube length - in spite of my opinion of importance above. In other words, if a frame is called 52cm, that number is referring to the seat tube length. Confusingly, seat tube is measured in different ways depending on manufacturer. Common ways are measured from the center of the pedal spindle to the center of the top tube where it intersects with the seat tube (C-C). Or, from the pedal spindle to the top of the top tube (C-T). Where this gets confusing is if you're comparing CC-measured frames with C-T measured frames. The two frames could be pretty much the same size, but the CT frame will have a stated size 1-3 cm larger. Some frames are also sized according to the distance from the pedal spindle to the very top of the seat tube, where the seat post emerges from it. This can be a good 2-4 cm longer than the same frame measured CC.

If you're garage-saling, you should actually measure the top tube length with a tape measure (center of seat post to center of head tube (semi-vertical tube that the handlebar stem goes into) and do a quick standover test. Be sure you make the top tube measurement on a HORIZONTAL line since some top tubes are slanted. You want the "horizontal" or "virtual" top tube length, not actual if the tube is slanted. With these two quick and dirty measurements, you'll be close enough, probably, to adjust stem, handlebars, seat to suit yourself.

For a rough guess at what top tube size you'll be needing, go to www.wrenchscience.com and plug in careful measurements of your own body.

MY WAG would be that you'll be on something like a 50 cm (CC seat tube) frame.