# Merckxmen



## ciclisto (Nov 8, 2005)

who amoung you can educate me on geometry of the corsa extra. on some I have seen the top tube and seat tube are square c-c (i.e. 55x55) on another I see 57x56. Do they vary or is this poor measuring? I am seriously looking at a corsa extra (slx) with chome fork. I have a custom steel 57x 56.5 and a stock 55x56 which both work. The one I am considering is 57c-c X 56 c-c. the weight is no big deal, Is the seat angle a factor ........ciclisto


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## tarwheel2 (Jul 7, 2005)

Unfortunately, I don't think all Corsas have the same geometry, but it sounds like this frame is very close to your current bikes. Some of the differences in sizes are no doubt due to sellers on eBay who don't know how to measure a frame properly, but some Merckx frames are just sized differently. Most steel Merckx have their classic "Century" geometry with relaxed seat tube angles. However, I have a friend with an older Corsa that has their "Criterium" geometry with a steeper seat tube angle. 

BTW, my Corsa 01 is size 57. It has a 57 center-center seat tube, 56.8 c-c top tube, and a 72.5 seat tube angle. The seat tube angle is important because a steeper angle (higher number) will make the top tube fit longer. For example, my Corsa replaced a Gios that had a 55 c-c top tube, but both bikes fit about the same across the top because the Gios had a very steep (74) seat tube angle.


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## ciclisto (Nov 8, 2005)

very good info "t" thanks , I am looking at a corsa exactly like you described, do you have any info on Schwinn Paramounts in columbus tubes from 80's Im shopping!!


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