bombadil fork crown hole

[ted]

The rear facing hole in the fork crown on my Bombadil is recessed a
bit like a brake mount, but its smaller.
When I put a Nitto Mini-Front rack on my SimpleOne I used the recessed
allen bolt from a side pull break.
That doesn't work with the Bombadil. But the the back face of the
crown where the hole is isn't flat like the front either.
Do any of you know why the recess on the back face of the Bombadil
fork crown is there?

Thanks,
Ted

[grant]

The crown is the same as we use on lots of other forks, some of which
have sidepulls...thats why the recess. It is easy to fill in with
right-sized washers or spacers, and it ought to be easy to mount a
rack. We do it a lot, and since the crowns come out of the same molds,
it's unlikely that your hole would be too small for anything.......
You could use a flat washer and a hex nut.
G

[ted]

Thanks Grant,

Your right of course, the rack mounts very easily.
When I thought the allen thing off a spare dual pivot I had lying
around didn't fit, I did go straight to the washer and nut route.
I used a sturdy wide dia steel washer (I think it came off an old side
pull brake) and the nylock nut that came with the rack.
Seems plenty solid, no complaints, no worries.
Maybe the allen thing I tried is a bit over size (never ben used), or
maybe I was just too careless trying the fit.
If I ever have occasion to pull the rack off, perhaps Ill try and
figure out my mistake. Or perhaps I won't.

Love that Bombadil, thank you very much, and perfectly pleased with
the Simple One too.

thnks
Ted

[William]

Punchline at the front.  Leave it the way it is now. 

Justification for the punchline:

It's true that SOME recessed allen nuts on brakes have a wide flange on the head.  In particular, in my experience, the ones that are used on a carbon fork often have a wide flange head.  Ones like that I am certain would not recess into the recessed part of your Bombadil fork crown. 

The other part that you would have run into with any recessed allen nut is that the BOLT part of your front rack is far too long to use any recessed allen nut.  The bolt part must not stick out from the crown if a recessed allen nut is going to work.  With any Nitto front rack that would mean you'd have to at least cut the bolt part short and potentially even have to thread that rod down a few more mm.  Or you'd have to come up with a stack of spacers on the front side.  All that is far too much work for a setup that is mechanically no better, and could actually be worse. 

[ted]

Yeup. Leaving it as it is. But ...

On my simple one I did cut the rack and use a spare allen thing. That
also seems just fine.
I did't have any trouble with running out of threads. I do have a few
washers as spacers on
the front side (on both bikes) which gives a bit more clearance for
the tektro 720 straddle
wire Hanger. Spacing it out seemed like the obvious thing to do, and
since then I think I
saw that suggested in a blug or reader or something. I see no reason
doing it that way is any
better mechanically, but I also don't see why it would be worse?

Could you expound on how using a allen nut might be mechanically
inferior to a big washer and hex nut?

thnks
Ted

[William]

the 'could be worse' comment depends on how you do it.  If you cut down the bolt part and don't need any more threads, then it would not be any worse mechanically.