Need Help on sizing

[d22money]

I know this has been a frequent question, but I am new to cycling. I am about to purchase my first bike online and I am having some second thoughts about my size. I am 6'0 with a 89 cm inseam. I went to wrench science and used their sizing program, which put me on a 61 or 62 cm frame center to top and a 59 cm center to center. What is the difference between these two measurements? I am looking at a 60 cm bike right now.

 

[boudreaux]

I know this has been a frequent question, but I am new to cycling. I am about to purchase my first bike online and I am having some second thoughts about my size. I am 6'0 with a 89 cm inseam. I went to wrench science and used their sizing program, which put me on a 61 or 62 cm frame center to top and a 59 cm center to center. What is the difference between these two measurements? I am looking at a 60 cm bike right now.

One is measured to the top of the toptube, the other to the center. How much different depends on diameter of TT.Frames are aslo measured to the top of an extended seattube.Better know what you need in TT length and seat angle to or you could be throwing money away.Online fit calculators are at best guidelines and a place to start,not absolute.

 

[Claes]

Boudreaux is making a good point there.

I think the lenght of the top tube might be more important to you. I have an inseam of 88 cm, same height as you. If you go for a 58-59 cm frame, you will get a more "racey" position, since you will have the saddle up higher, and the handlebars lower. If you are looking for a more comfy bike, go for 60 cm, that will have "old style" amount of saddlepost showing. 58 cm frame would have more than "old style" amount of seatpost showing. I am now talking about non compact frames, "old style" or whatever I should call it. Normal? Normally there would be 1-2 cm difference in top tube length between 58 cm frame and 60. That can most the time be easily compensated with your stem. Just make sure that the bike you put together not require you to run an "extreme" stem, such as 70 mm or 150 mm and you should be ok I think. Could you give me the link to the online frame you are looking at? Send me a pm if you want to. I did lots of research just a few weeks ago, and bought a bike and I seem to have similar sized body to you.

Cheers.

 

[BikeyGuy]

Check out the "Colorado Cyclist" bike fit guide.
You might find it helpful.
http://www.coloradocyclist.com/bikefit/

 

[fredf]

I like Clae's advice. I have an 85.5cm inseam and just bought a 58cm Trek 5200. I might have been able to go with a 56cm but I can easilly straddle the 58cm and the seatpost is extended only 5". I have a 95mm stem and the setup works great because by going for the larger frame I can have my bars just slightly below my seat level.