Monday, January 31, 2011

California - Day 7...

I woke up today a bit bleary.

Okay, a lot bleary.

Last night I was up until almost 2:30 AM. That's local time; that means 5:30 AM back at home.

And when I went to sleep I had no bike to speak of.

My host did some analysis last night, theorizing that the welding affected the BB30 shell. When I finally got going this morning, I checked in brighter light, with a more clear head. I decided to check the shell's roundness by using a bearing for comparison.

We initially thought the bearings were being radially compressed. That means they were getting "shrunk" in diameter. Or radius, as the case may be.

That's really hard to do. Think about a round thing like a bearing. If you squeeze it, it'll tend to bulge out elsewhere.


And that's what was happening in the frame. The BB30 shell, which I'm sure was perfect when it was made, warped a bit due to the welding. Problem is that it's hard to source BB30 facing tools (right now I think they're unavailable). This seems a bit ridiculous because any time you weld a BB30 shell it'll warp just a touch, and you need to be able to get it right.

Cannondale and other big manufacturers do their machining after the frame is built. A small outfit needs that option, but it's simply not out there.

Note "line" to the left of the bearing. That's daylight coming through a gap.

Neither I nor the host have a micrometer so I couldn't measure and file. Nor could I use a pre-existing tool to face the thing; we didn't have one of those either.

I used the "visual gap" and "rocking" method to see where I had to file. A gap meant no filing at all. If I could rock the bearing back and forth, the "pivot" areas needed to be filed.

I'd given up yesterday after many hours of checking, filing, testing, refiling. I stopped when I started getting delirious, unable to maintain coherent thought, forget about conversation.

Well, I should have kept going because it took only a few minutes and one test fit to install the BB30 bearings.

After judicious filing, I got the bearing in without much trouble.

The other bearing. Also in without much trouble.
You can see the c-clip limiting how far in the bearing sits.

Bearing shield (black thing) and spindle.
It's still stiff - note the crankarm's unsupported position.

There's still some compression going on because the crank doesn't spin at all. But it went in okay, it turns, and there's no notchiness (last year the bottom bracket was so tight that the crank arms "indexed" as they turned).

I decided that's the way it'll be and proceeded with "the easy stuff."

Rear brake mounting nut access is tight.

I brought my Torx tools specifically because I knew I'd have to adjust the brake shoes. I didn't think it'd take me 30 minutes to find the stupid tools. I stuck them in my backup pair of Sidis. Note to self: check shoes first next time.

Cables, housing, tape, optimistically laid out.

You can see the theme here. Black and blue.

Front derailleur test fit, with K-Edge front chain guard.

The front derailleur mount put the tail of the derailleur into the chainring teeth. I knew I'd seen this before and couldn't remember the solution. After letting the problem simmer in my mind, I realized I need to simply file the braze-on mount until the mount's angle matched what I needed.

15 minutes of filing and testing and, voila, front derailleur.

Nokon gold link, downtube cable housing stops.

Nokon sets get assembled at a factory so I had to remove the links to "right side up" the gold Nokon key link on the left side.

The segment thing is nice because you can match housing lengths right and left, and you know it's exact.

Ran the teflon liner thing all the way to the bottom bracket shell.

I ran the inner liner the full length of the cable whenever possible. I ran them down both derailleur cables to the bottom of the downtube.

The brakes both have full length housing (the internal one has no stops, the housing just goes through the top tube). No worries about liners there - just run them through the whole length.

I want the blue to show so I used the beat up silver and black Nokons to fill in under the tape.

Nokon supplies just enough segments to cover the exposed portions of housing. Since I like their functionality most, I now put Nokons under the bar tape (normally you use a cheater piece of housing, included with the Nokon kits).

I have 3.5 bikes worth of Nokons (a friend gave me half a kit a while ago), and I only have two bikes with Nokon housing. I can go the full length in Nokon, just not in one color.

Teflon liner poking out of the hole in the seat tube, allowing the cable to go to the front derailleur.

Since the opening in the seat tube has no liner I had to use a Teflon liner to prevent the cable from garrotting the seat tube until it split in two.

Almost done. Chain and tape and SRM wiring harness to go.

So, I've left the chain, bar tape, SRM wiring, and maybe a seat post cut for tomorrow. I'm just too tired now to do anything and I don't want to screw anything up.

Good night all!

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