Do we need to re-define downhill mountain bike geometry?

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weeksy
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Do we need to re-define downhill mountain bike geometry?

Post by weeksy »

https://www.pinkbike.com/news/grim-donu ... -2020.html

Whilst i think it looks horrific and probably rides horrifically, there's no doubt it seems to be able to hustle down the hills.

The Grim Donut is clearly flying.
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Mr Moofo
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Re: Do we need to re-define downhill mountain bike geometry?

Post by Mr Moofo »

It looks like a HD Chopper.
I can see why to does down hill well but I imagine it wanders like a bastard uphill - and in anything other than a downhill it flops from side to side a bike.
TBH, I think Geometron maybe have reached the point of all round acceptability, so it is good that people test boundaries - then Cotic can follow ...

But no doubt there will be new thinking, to sell new units in the next few years ...
26 inch wheels will come back ...
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Re: Do we need to re-define downhill mountain bike geometry?

Post by Couchy »

Obviously a one trick pony and only any use at downhill centres with uplifts. I'm still waiting for a tarmac downhill course and some sort of gravity cycle fitted with slicks so we have to wear knee sliders :)
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Re: Do we need to re-define downhill mountain bike geometry?

Post by weeksy »

Couchy wrote: Wed Sep 23, 2020 2:52 pm fitted with slicks so we have to wear knee sliders :)
My lad is practicing this in the car park. Any day now he's going to be coming home with his knee in bits !
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Re: Do we need to re-define downhill mountain bike geometry?

Post by millemille »

Been watching the Grim Donut with interest, I've got a plan over the winter to build a bike park only, Amish, DH bike using the bolted together flat plate aluminium frame concept and the reach and head angle will be adjustable and am considering whether to allow the head angle to go as extreme as Grim Donut's for shits and giggles...

Pinkbike have also done one of their "hucking to flat" video's and watching Grim Donut's forks compress is interesting as they don't appear to be flexing and fighting the bike's forward movement as much as those fitted to the bikes with a more conventional head angle.