# Help understanding Merckx geometry



## jroden (Jun 15, 2004)

I'm comparing my MX Leader with a newer specialized compact. When I measure from seat nose to handlebars, they are more or less the same. When I drop a plumb line measure seat nose to center of bottom bracket, the leader seat sits quite a bit (couple inches) further back. I'm sure the seat angle on the Merckx is more slack, but it suprises me that the "cockpit" length is the same, while the seat to BB relationship is so different.

Even with the seat jammed all the way back, the Specialized is much further forward, I think I know why it makes me sore to ride it after spending so much time on the Merckx, I'm using different muscles.

Is this all a factor of seat tube angle? Are compact design frames more prone to this sort of geometry?


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## atpjunkie (Mar 23, 2002)

*Merckx's are known for that*

'behind' feeling and yes that is a product of ST angle combined with everything else.
your cockpit area is the same but the Specialized does this by putting more of the rider into the front center. there's been a bunch of discussions about this in general (regarding ST angle combined with TT length,HT angle and cockpit length. the merckx is putting more of you behind the BB, so if you can't get equal knee to pedal axle plumb bobbing then you can never really see the differences in cockpit


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## jroden (Jun 15, 2004)

so, is there some conventional wisdom about the advantages of sitting the rider back this far, or is it just an issue of the length of the leg from the knee to the hip? Is it supposed to make you accelerate faster when you are over the pedals more, or is it all just a fit thing?

I do like sitting back further, but I have ridden some good races on the other bike too. It's an interesting difference between the two.


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