Lightest complete downhill bike?

PB Forum :: Downhill
Lightest complete downhill bike?
Previous Page | Next Page
Author Message
Posted: Mar 15, 2019 at 18:19 Quote
lightest complete downhill bike?

Posted: Mar 16, 2019 at 7:47 Quote
Do you know what bike

Posted: Mar 16, 2019 at 10:04 Quote
For downhill it can actually be a disadvantage is the bike is too light. A bit of weight can make the suspension work better and make the bike more stable.

Posted: Mar 17, 2019 at 8:54 Quote
How light is “too” light for downhill?

Posted: Mar 17, 2019 at 16:56 Quote
BeaverCreaker wrote:
How light is “too” light for downhill?

There´s no definitive answer to that question. it also depends on where the weight sits on the bike. A 15kg bike with super light wheels may feel like shit whereas one with 15kg and heavier wheels will track better and not get thrown off track as much. On the flipside very heavy wheels will slow down response and hinder suspension performance due to unsprung mass.
You see, it may be possible to end up with a very light bike by using air suspension, light saddle, bar etc, but it may end up being for nothing if the weight isn´t safed with the right intentions on the correct parts.
People focus way too much on a single number, be it chainstay length, headangle or in this case weight.
They do not work as an isolated measure of performance.
Also, for a guy with 150kg it most likely won´t matter how light the bike is. He´ll make up for its lack in stability with his own weight, whereas a super light guy may end up with a skiddish feeling bike rather quickly, but on the flipside he most likely needs to avoid a bike that´s too heavy just as much as it would not mesh well with his power to weight ratio.

So just go ahead and build your bikes within a reasonable weight range and you´ll be golden.

Posted: Mar 17, 2019 at 19:35 Quote
Realistically, a very light rider could go under 30 lbs with a "proper" DH bike, while a heavier rider probably can't go that low without sacrificing performance.

Some heavy components are heavy because they're made cheaply or designed poorly; others are heavy because the extra material provides more benefit than harm. You can substitute lighter parts and less travel until you've made a 17 lb XC racer; there's no clear line as to when it's no longer a DH bike.

I just posted this elsewhere:

Many years ago, there was a thread in which a kid built up a sub-30 lb DH bike. It had 7" of travel, a double-crown fork, 4-piston brakes, and 2.4" tires, so it's a downhill bike, right? Sounds reasonable, but ...

- The shock was a 250 g XC unit.
- The brakes used 6" rotors, if I recall correctly.
- The 2.4" tires were 530 g Continentals with Supersonic casings (XC, race-day-only casings).
- Components were selected by weight, with no regard for strength or stiffness.

Unsurprisingly, it was a huge disappointment. Some people just aren't into learning from history and want to try it for themselves.

Posted: 2 days ago Quote
I remember seeing a Pivot Phoenix around 32lbs (Fox 40/X2, Reynolds wheelset, Race Face SIXC components, Saint and possibly Schwalbe SuperGravity casing tires to save weight versus full DH casing wire bead -- 200g a tire saved).

Posted: 2 days ago Quote
gramboh wrote:
I remember seeing a Pivot Phoenix around 32lbs (Fox 40/X2, Reynolds wheelset, Race Face SIXC components, Saint and possibly Schwalbe SuperGravity casing tires to save weight versus full DH casing wire bead -- 200g a tire saved).

Exactly. A very light rider might even get away with the new Maxxis EXO+ tires, saving a further 200g per tire. This rider could also use XC bar, stem, cranks, etc. to take off nearly another pound. The frame could be made with a lighter carbon lay-up, saving nearly another pound. Voilà, sub-30 lb DH bike, but only for the right rider.

Posted: 7 hours ago Quote
R-M-R wrote:
gramboh wrote:
I remember seeing a Pivot Phoenix around 32lbs (Fox 40/X2, Reynolds wheelset, Race Face SIXC components, Saint and possibly Schwalbe SuperGravity casing tires to save weight versus full DH casing wire bead -- 200g a tire saved).

Exactly. A very light rider might even get away with the new Maxxis EXO+ tires, saving a further 200g per tire. This rider could also use XC bar, stem, cranks, etc. to take off nearly another pound. The frame could be made with a lighter carbon lay-up, saving nearly another pound. Voilà, sub-30 lb DH bike, but only for the right rider.

And the right track... Even if the rider weighs like 130lbs, if they are going World Cup speed on rough terrain those tires will be destroyed or rolled off the rim in the first turn (picture Troy Brosnan cornering). If it was a smooth track with pedaling then the compromises might make sense.

Posted: 3 hours ago Quote
gramboh wrote:
And the right track... Even if the rider weighs like 130lbs, if they are going World Cup speed on rough terrain those tires will be destroyed or rolled off the rim in the first turn (picture Troy Brosnan cornering). If it was a smooth track with pedaling then the compromises might make sense.

Some riders aren't even 130 lbs. As I said, a set-up like that would be for a rider far outside the middle of the bell curve. And yes, other factors could contribute, like a smooth course, absence of sharp objects or harsh impacts, etc.

Previous Page | Next Page

 
Copyright © 2000 - 2019. Pinkbike.com. All rights reserved.
dv65 0.014153
Mobile Version of Website