[Dogboy]

Quick tech question: I understand that the rear hub is offset on the D8 to give it an effective 57mm chainline. Is the rear hub dished like a traditional build (centered laterally in the rim) or is it offset (no dish)?
Many thanks.

 

[jackalope]

^^
Interesting...I presume the D8 has a 150mm rear hub spacing, no? Thus, I *thought* that would thereby preclude the need for a dished rim (plus help out with chain line)...Of course, I'm really only parroting what you told me up in Canada

Btw, is do you know if Michelle (i.e. Suboptimus Prime) getting back tomorrow? I NEED my Preston back ASAP...

Also, we're heading up to le montagnes tomorrow to do Wilsons Creek on Saturday and Sugar on Sunday in case you can make it...

 

[Dogboy]

It's actually a 135mm rear that is offset to give you the same effective chainline as a 150mm rear.
Anybody???

 

[S.K.C.]

Heh - I was wondering when this would come up...

The rear triangle on the Demo 8 uses a 135mm rear hub and is offset by 6mm. This is done as a means to compensate for the 150mm rear hub that the Demo 9 uses, because the Demo 8 AND the Demo 9 share the same frame geometry and build specs. -Makes em' easier to produce.

The rear wheel is ZERO dish as a result.

Edit: "Actual" Chainline on BOTH bikes is 55mm
"Effective" Chainline on BOTH bikes is 48.5mm (Seat tube is offset towards the drive side)
- As listed in the 2005 Demo Manual from Spesh -

Just went through a new rear wheel build last month myself...

Hope this helps.

 

[Dogboy]

Thanks for the info S.K.C.! That's exactly what I needed to know. Out of curiosity, which hub did you use?

 

[S.K.C.]

No problem...

...well the rear hub I'm running right now is a Q/R, DT Hugi FR.

It's pretty tough, but I'd prefer to have a T/A (Through Axle) for the added stiffness. Possibly a Hadley DH, or if I can get that LOAN approved, a Chris King ISO Disc hub w/ the Heavy Duty steel drive shell...

 

[Soul Rider]

I have a Demo 8 as well. THe drive line is nice and straight with the 6mm offset rearend. THe Demo 9 and the Demo 8 are completely different bikes (I have a Demo 9 as well) the main reasoning from the Spcialized R&D guys it to straighten out the driveline/chainline.
I originally built the rear wheel with dish, like a conventional rear triangle. It worked but another item raised it's ugly head...the chain actually hits the tire knobbies. Now it's all good!

 

[J5ive]

So, same length spokes for both sides?

 

[Electric_City]

Old thread, I know. But is a standard 135mm hub with a TA compatible with the Demo 8 frame? Do you just offset the dish 6mm to the disc side of the wheel? A buddy has a barely used 05 but no rear wheel. I'm just wondering what the bike needs to get up and running. Is there a special axle? Thanks EC

 

[Dogboy]

Old thread, I know. But is a standard 135mm hub with a TA compatible with the Demo 8 frame? Do you just offset the dish 6mm to the disc side of the wheel? A buddy has a barely used 05 but no rear wheel. I'm just wondering what the bike needs to get up and running. Is there a special axle? Thanks EC

Rear hub needs to be 135x10mm - qr or thru-bolt will work. The wheel will have zero dish - rim equidistant from either end of the hub.