I think you guys tried to argue, one about tomatoes, the other about cars, and to some degree both of you are right :-). There are many kinds of trails you can ride with different bikes, and nowadays for every produced frame that has a difference of 0,1° in slope angles of the upper tube you get a new name for it. A crossbike is basically a bigger mountainbike (28') with slim tyres, a speedbike is the same frame, maybe not as nobbly tyres and with race bike gears instead of mtb crank and stuff, a cyclocross bike is in between them plus drop handle................... oh how I hate that!
If you really like to go fast get a superlight aluminium or steel frame, if you have money get a titanium one (titanium and aluminium alloy that is, called...
titanal over here!!!!!), get lightweight rims and build a single speed bike. I admit these are mostly used by fashion faschists and apple users
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, but in the Netherhollandslands tey are THE weapon of choice. No loss in the transmission, easy to accelerate and great topspeed performance!
An internal 4 (3, 5,7,8,11,14-) gear hub is stupid and kills power.
greetz
der butz