Specialized Crux: Steerer, Replacing Fork, oddness

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prendrefeu
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by prendrefeu

Yo.

I've parted out my Specialized Crux (aforementioned in another thread) and in doing so got to weigh the individual components. A few things came up:

First, the fork... weighs in at 567g with crown race and this spacer thing below the race. Unfortunately I don't have a crown race remover, nor a remover for that spacer thing, so I have no idea what that spacer itself weighs. Anyone have insights into this?
Image

My first thought was WTF is this?! :hmm:

Then I took a look at the headtube:
Image

Apparently there's some extra distance between where the crown race would meet the lower headset bearing and the bottom of the headtube, hence the extra spacer. It also looks like I have some optional space to dremel out excess tubing and lose 10g or so, but that's another note.


Which brings me to the fork replacement I'm considering:
This one... simply by way of budget (because an ENVE fork is out of my budget at this time) -
Sette Tapered Fork - claimed weight is 500g.
Image

I'll also need to add in a spacer apparently, similar to the one that is on the existing Crux fork.
Could this spacer be made of carbon fiber? I could have one made.

Is it worth the investment to get a full CF fork? Or should I just stick with the existing fork with alloy steerer?
Are there any other options out there that would work with this Specialized headtube design? (see what I did there?) I'm even wondering if the Sette fork would work considering how far up the 1/2" size rises from the crown.

Intentions of the build will be:
60% training/trail riding in the local mountains, heavy thrashing anticipated, lots of climbing on hard packed dirt (Southern California)
30% thrashing around at a few races during the season
10% idle cruising on backroads
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by Weenie


thisisatest
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by thisisatest

the "spacer" may or may not be a separate piece. it is there so the lower bearing is inline with the lower wall of the down tube. it makes little difference in metal frames, but for the carbon frames, it can help keep things strong. the design also has the potential to allow the fibers in the crown area travel up to the steerer more gradually.
i don't think any non-specialized fork is going to work. no fork maker that i know of offers a raised crown race seat. simply using your own spacer would be a bad idea, also, as the fork makers design the load to be applied at a particular spot, not an inch above it.
you could, conceivably, face the bottom of the head tube a LOT, and then run whatever fork you like, but of course you'd be dropping the front of the bike down a bit and messing with the angles. maybe a 29er fork would work then, but then you wouldnt be saving any weight...

Colin
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by Colin

IIRC Specialized uses a "campy" style crown race, not sure if anyone else makes a cross fork with that style crown race. Your best bet (or maybe your only option?) would be to try and get one of the full carbon forks from an Sworks.

tonytourist
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by tonytourist

The spacer is there because the lower headset bearing sits higher in the headtube than standard. That should be an easy part to order if you can't get the stock one off. My friend went through something similar when he replaced his fork on his mountain bike. Why not keep the stock Crux fork, save up for what you really want and shave weight elsewhere? Specialized really should have put a carbon steerer on the these bikes :evil:

BrianAllan
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by BrianAllan

if I recall the new carbon disc fork features an all carbon steerer.

nitropowered
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by nitropowered

I think you are stuck with that fork, unless you get another spec fork with a carbon steerer

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prendrefeu
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by prendrefeu

I'm getting in touch with Specialized now to see what they have on hand.
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Briscoelab
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by Briscoelab

They don't make a full carbon fork with a tapered steerer tube.

I think my frameset came with a spacer that lets you run a regular taper fork though. But I might be mistaken on that one. This is similar to what they used to do on their MTBs with tapered steerer tubes. For those, I know they made a spacer/adapter that went into the frame and let you use a regular fork. Perhaps one of those might work for you.

foofighter
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by foofighter

Whisky parts has some new forks coming out at pretty reasonable prices. They are the reincarnation of winwood(a qbp brand).

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prendrefeu
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by prendrefeu

I may wait for the Whiskey brand parts to show up, Specialized inquiries have been quiet. Supposedly the only full carbon CX forks they have were used on the pro bikes in recent season races. I saw an initial offering of the Whiskey-brand CX fork that came in at a near-ENVE weight.

As for the spacer: I took a look at it... it's really not that complicated, it's just a spacer sitting on the crown. One could easily be made out of carbon fiber... or delrin! :twisted:
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prendrefeu
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by prendrefeu

Does anyone know of other Specialized models that feature this spacer design detail?
The purpose is to raise the placement of the lower bearing relative to the downtube, which increases durability, stiffness, response and more, while keeping the headtube at it's necessary length.

I know the new Specialized Tarmac SL4 uses this feature, albeit with a 'new' standard of 1-3/8" lower bearing size. :|

However, as the 1-1/2" lower was common for a while with Specialized frame designs, is this spacer-on-fork-crown found on any other frames in recent years?
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atx6speed
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by atx6speed

Did this ever get resolved? I'm trying to swap the fork on my 2011 Allez Comp E5 and am having the same issue where there is 10mm of extra material on the crown of the fork that elevates the crown race so that it meets the lower bearing. The only solution I have found is to some how lower that bearing down in the headtube so that it meets the top of the crown race.

Apparently Specialized has used two different head tube designs. The older one is called "higher position" and places the lower bearing higher in the headtube (the current situation). The new design is called "lower position" and places the bearing lower in the head tube where you'd find most lower bearings. This allows you to use any fork that is aftermarket.

I went to my LBS and ordered Specialized part number S092500004. This PDF document covers the change and the necessary part to order. My question is whether anyone has tried this or not and whether or not there is an alternative solution should this not work?
http://service.specialized.com/collater ... -Guide.pdf

Briscoelab
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by Briscoelab

I really think that would work... IF they Crux is using the same design specs they used on the MTB forks. Never know with Specialized. I used those adapters on a 2010 S-works MTB frame.

atx6speed
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by atx6speed

Here's to hoping. As long as the chamfer is the same as the mountain frames I can deal with the adapter being slightly too thick. The adapter should be here this Friday.

by Weenie


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prendrefeu
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by prendrefeu

My problem didn't get resolved, it went to the backburner as a friend and I went from discussing milling a special delrin part for this to manufacturing other bike parts (stay tuned... :mrgreen: )

Could you post in this thread if it resolves the problem? I'd love to use 'any' 1.5" tapered fork if this allows me to lower the bearing placement in the headtube.
Exp001 || Other projects in the works.

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