Sam Hill's Worlds DH bike

[Capricorn]

some interesting stuff..

 

Specialized founder Mike Sinyard with Sam's bike:

http://nsmb.com/assets/images/A_events2010/IB2010/3/fergs/_I4I2103.jpg

 

6 cog cassette on custom DT Swiss hub:

http://nsmb.com/assets/images/A_events2010/IB2010/3/fergs/_I4I2089.jpg

One of Jason's projects this year was a streamlined drivetrain. He reckoned that 9 or 10 speed was overkill and that 7 would be just fine. He then decided that dropping down to a 9 tooth cog could bear some fruit as well - but this wouldn't work with a conventional rear hub. DT was enlisted to modify the free hub body to allow 9 and 10 teeth cogs to be added in place of the usual 11 speed highest gear. This higher gearing allowed for a smaller chainring as well so Jason had a custom 31 tooch ring made as well as a 30. A smaller metal sleeve replaces the usual splined aluminum body for the first few cogs - which are machined to fit together and then mesh with the 11 tooth cog for support.

 

Jason also walked me through some other innovations in the Demo 8 I wasn't aware of. There is a concentric bolt at the rear shock mount that can be rotated to increase the BB height by 10 mm (the Demo starts out an industry- lowest at 13.5") while steepening the headtube by .75 degrees to 64.75 from 64. The Demo also has a very short headtube because of a proprietary welding technique that allows the top of the toptube and the bottom of the downtube to connect at the upper and lower edges of the headtube with no overlap.

http://nsmb.com/assets/images/A_events2010/IB2010/3/fergs/_I4I2097.jpg

 

On most aluminum bikes the headtube must extend further to allow room for the welds. This means that you can loosen your fork crowns and slide them up or down to tweak the head angle yet again. Because of this you can adjust the bb height and head angle independently to a certain degree or use them in tandem to make the maximum adjustments.

 

The rest can be read over here.

[loveme.DH/FR]

Thanks Cap!

I totally belieive that theres no reason for 9-10 spd DH bikes. Its overkill. I hardly ever use more than 2 usually 11t and 13t and never change while riding.

 

That bike looks soooo sweet!

[patches]

yeah... 6sp is more than adequate...

 

heck, my DH bike only has 3 gears that work properly (mis-aligned/bent RD means the other 6 jump a bit)

[Capricorn]

yep, that bike does things to me... oi

 

hopefully, i can get a 2011 model if things pan out, which reminds me to message that kind soul

[Stryder]

The bike looks so small?

 

Or is it a tricky photo?

[Stryder]

Frikken awesome though

[Capricorn]

stryder: u go ride last night?

[Stryder]

No sir, gonna try for Saturday.

[Bos]

DT was enlisted to modify the free hub body to allow 9 and 10 teeth cogs to be added in place of the usual 11 speed highest gear. This higher gearing allowed for a smaller chainring as well so Jason had a custom 31 tooch ring made as well as a 30.

 

Ive been thinking this just the other day..

 

Im not sure if the 9T cog might put to much stress on fel links or something, but that would eliminate the need for Huge 42T blades even on xc bikes, and we would definately never see 3 blades again.

[Capricorn]

No sir, gonna try for Saturday.

 

kewl, cos i wanna bring my camera with

[Stryder]

LOL, pressure is on!!!!

 

Gonna try for around 12:30pm, have some stuff to do in the morning

[Capricorn]

hehehehe. i just thought that since i'm off the bike, i wanna get footage of others guys. we need to build our own stoke. so slash berms and shred off cambers.. we need our own ****..

[Capricorn]

oh and i plan to work on the track. so expect just about every weekend to be track building. come build, or build and ride to test. that would be awesome

[Stryder]

sounds like a plan

 

hopefully the weather holds this naweek, i am afraid of melting