I might be a few years out of date with XC racing trends so I apologise in advance, but...
If you look at the bikes in the Olympic XC race they're invariably carbon hardtails, and most were 29ers from what I could see. But also, curiously, they've got massive seatposts. Really aggressively sloped top-tubes. Annie Last's Boardman has a seatpost that's as long as the seat tube...
And then of course Fontana snapped his seatpost in the final lap, almost losing him the bronze.
Is this all aesthetic? Something to do with overly stiff carbon frames? Weight?
Haven't you noticed that trend around here? Most people appear to get bikes too small for them (chuckability) and put 400mm seat posts on to compensate.
Except the racers are lightweights. STW-ers are mostly not!
Similar to Road,
Compact frames, Same length top tube but shorter seat tube,
More clearance stiffer and lighter.
No need the old fashioned 1" below your balls sizing here.
It is really noticeable on the road. Look at some of Brads setup pictures.
Tiny frame, massive seatpost, what looks like a 140mm stem and the saddle on a layback post as far back as it'll go.
Wouldn't any banefit in stiffness be offset by a long post and stem?
FWIW top level athletes have plenty of bikes so longevty is not a concern.
Weight will play an important part - the Team GB road frames were custom made so there must be a reason for it...
It's a shame they didn't ask STW forum for their expert opinion on bike setup, maybe then we would've won some medals in the mtb.
Wouldn't any banefit in stiffness be offset by a long post and stem?
In terms of ride yes. but power transfer no.
At a show I asked one of Pinarello guys about it. He said you could afford to put more strength into the chain stays and around the BB by going to the compact frame design. The weight would be the same if not slightly less than a traditional frame.
It's a shame they didn't ask STW forum for their expert opinion on bike setup, maybe then we would've won some medals in the mtb.
The Stw expert opinion was that the course was crap and grannies could ride it. so this bike would have recomended:
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(The saddlebag is to hide the beer your not aloud at the course)
Haven't you noticed that trend around here?
Well yes, but I didn't realise that trends of STW were being followed by Olympic athletes. Although come to think of it, I'm pretty sure I saw one of the backmarkers riding a rigid singlespeed fat bike.
Marco Fontanas seatpost was pretty short by the end!
compact frame, lighter, stiffer so better power transfer, long seatpost is a bit more forgiving so a comfier ride, makes perfect sense to me hmmmmm...
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I've not really looked into it but I don't think the stiffness between your bum and the cranks is not the issue but it's more the stiffess of the frame between the back wheel, cranks and bars. If you are out of the saddle of course this is even clearer.
Similar with the road bikes with really small frames meaning much shorter tube lengths so very stiff, compact frames. This then gives the ride more room to move around which is what many people (including myself) like in a frame.
Superficial - Member
Is this all aesthetic? Something to do with overly stiff carbon frames? Weight?
If I were to hazard a guess I would say a long post would allow a rider to remain seated longer thus conserving energy for when it's needed.
that looks normal to me, esp for a woman's bike. i'm a 5' 10" guy and i like my seattube collar about level with top of back wheel. a 29" will look even lower. can't see why anyone wouldn't want lots of standover tbh.
if anything this course was more "all mountain" (sorry) than most, with wider bars and some FS bikes doing well.
[i]a long post would allow a rider to remain seated longer thus conserving energy for when it's needed[/i]
the distance between top of sadlle and pedal remnains constant - it's the seat tube:seat post ratio that changes.
My view is that they really wanted to run dropper posts for the tech bits but were too embarassed when it came to the crunch 😉
