Specialized Crux: Steerer, Replacing Fork, oddness

[GregMay]

..I hate how many standards there are across the industry. ..

Its starting to take the pi$$ how many 'standards' there are. Standard means 1. We don't have several metre standards do we? No.
/rant

Either way, i just sent the guys at Sepcialized a tweet and they came back pretty soon, good service!

[thisisatest]

i measured the cane creek bearing and one that i think came from a cannondale. the difference? just 0.6mm, so almost like no difference at all...

i doublechecked some bearings today:
the cane creek bearing was less than 6.5mm tall.
the specialized bearing was 7mm tall.
the cannondale bearing (until now unmeasured, i had them mixed up) was 8mm tall.
things are getting fuzzier.
on a tangent, cannondale uses a completely different crown race than everyone else, and a different steerer crown OD to go with it... in the end it doesnt matter, unless you only have a cannondale headset and an Enve fork...

[mcatano]

The next issue is finding a washer that will work. We thought about it for a while and ended up cutting off a piece of the crown race setting tool to actually make it work. It had the perfect inner and outer diameter and is really good anodized aluminum. It took quite a few tries and cuts to get the material off, so needless to say the cut isn't very clean.

If you ever need to make a washer like this again, the rule of thumb is that for any given OD, a piece of tubing 1/8" larger with a wall thickness of .058" will give a perfect slip fit. eg, For a 1-1/2" steerer, you'd use a piece of 1-5/8" x .058" tubing.

[atx6speed]

You guys are AMAZING. So much help here, really. I made a bit of progress today:

This is the old fork. Notice the weight and the huge chunk of material on the fork crown.


Here's the new fork without the ITT nut inserted:


Close-up of the normal fork crown this fork has:


This is the washer we cut off of a crown race setter (before sanding it down smooth):


The weight of the washer we made:


The adapter from Specialized:


Weight of the adapter:


How they go together (adapter was on bottom in this photo):


Weight of the combo:


How the adapter fits in the headtube:


Lastly, the weight of the fork with the ITT nut, but without the crown race or washer:


After we sanded down the washer we got everything assembled and so far the fork works. We still have a few remaining tasks before the project is done:
1. Figure out binding on top bearing (I'm using a custom dustcap, so this is sort of unrelated to the fork)
2. Torque all bolts (4 on faceplate, 2 on stem, 1 on headset, 1 on brake caliper)
3. Install new shifter (this was a warranty thing that we took care of while the bike was there)
4. Keep sanding the washer to thin it down some (make the cut nicer) and get the gap between the fork crown and headtube to shrink (the washer is visible from the side)
5. Redo my spacers (Easton recommends a 10mm on top and I have a 15 on bottom. I would like to do 5 on top and 20 on the bottom)

After we do that we can call this project done. I'm sort of wondering why the washer we're using is showing up on the outside and not inside the headtube with the crown race. Other than that I am very happy and can't thank everyone enough for all the help. If you guys want more information or measurements let me know since I'll be heading back to the shop in a few days.

[JBV]

Wow, thanks for the detailed post!

One question, I think (I didn't look it up) the Crux fork has 48mm rake, and I think Easton only comes in 45mm. Did you want to slow down the steering that much?

[atx6speed]

Wow, thanks for the detailed post!

One question, I think (I didn't look it up) the Crux fork has 48mm rake, and I think Easton only comes in 45mm. Did you want to slow down the steering that much?

I'm actually running it on the Allez, so the rake should be the same (45mm). Hopefully a combination of this Specialized adapter plus a washer should help many F.A.C.T. fork owners out with using an alternative fork (like on the Crux).

[Rush]

I'm bumping this thread.

A few years ago I bought my son a second hand extra-small Specialized Crux for his first 'grown-up' bike. He's now 15 and will soon outgrow it. I'm looking to hand it it down to his younger-sister. The bike is probably a 2012 model and for piece-of-mind I'd like to replace the fork.

This is where the fun begins.

My local bike shop picked apart the lower headset bearing and determined that the Crux uses an MH-P21 bearing : example.

Here are the dimensions.


The fork used in the Crux is a 1-1/8" to 1-3/8" taper.

Of course, no-one makes 1-3/8" cantilever forks anymore. ENVE made both 1-1/8" and 1-1/8" to 1-1/2" tapered back in the day, and Whisky still make a cantilever fork in 1-1/8".

The inner diameter of the MH-P21 bearing is 37 mm, so if I want to keep that, I can't use a 1-1/2" tapered fork (which is 38.10 mm).

So there appear to be a few options:
1) Contact Specialized USA to see if they have any old forks left. Specialized Australia didn't.
2) Make my own crown race so a 1-1/8" steerer interfaces with the 37 mm inner bearning diameter and 45 degree chamfer.
3) Try the Lauf crown race adapter - link. This interfaces their 1-1/4" steerer tube into the MH-P21 bearing recess. I could make a shim which then allows this adapter to fit onto a 1-1/8" fork.

The 'standard' of this lower fitting is IS49 according to this Crane Creek poster. It seems Specialized still use it for their current-model Crux - see 2020 Crux advertised with 1-3/8" lower bearing.

Here is what the existing crown race looks like on the Specialized fork. The crown race is bonded to the steerer tube which makes direct examination and measurement difficult. (Although I can't seem to attach/upload a file to this reply).

[petromyzon]

Seems like a bunch of time and effort to go through to replace the fork on an old bike if you don't know it to have been crashed hard or otherwise have any issues?

I completely agree it is easy to worry about components particularly on the bikes of loved ones, and once you have thought about a possible failure it is hard to get the issue out of your head. But I also don't know many people who replace bike components prophylactically in the absence of a crash and with a normal external appearance.