Sunday, October 26, 2008

My Turn

I've been working on this bike a bit at a time for awhile (other things keeping me busy :-), but it's finally done. This is the Redline bike I had built up last year, but that suffered the stripped bottom bracket.

If you recall, the BB (English) stripped, and I had Aaron tap the non-drive-side as Italian. However, rather than have a frame with one side threaded Italian and one side threaded English, I opted to tap the drive side Italian as well. (Although there's something to be said for keeping the right side English: the reverse drive-side threading of the English standard avoids the tendency of the drive side cup to unthread dueto precession.)

This was my first thread tapping project, and I was using the least expensive tap set I could find: Icetoolz. We'll see how it goes. As a precaution, I used thread-lock on the drive side threads.

However, since the Italian BB is 70mm wide and the English is 68mm, I opted to try to center the BB in the shell by adding a 1mm spacer to the drive side. I couldn't find a spacer that would fit around the slightly larger (in circumference) Italian cup, so I snipped apart a spacer for English BB cups, and inserted that. You can see the tiny gap between the BB shell and the flange on the cup in the photo below. I don't know if this was strictly necessary. We'll see if it holds. I've been riding the bike for about 2 weeks, and so far, so good.

The other thing that's new with this bike is the front brake is a mechanical disc brake: Avid BB5 Road. I kept the rear brake cantilever. When I'm certain I've installed and adjusted the front one correctly, I'll install a disc on the rear, too, and I'll never worry about rim wear again.

Now I'm building up a similar bike for Carol. I got this year's version of the Conquest frame on eBay, and I've ordered brakes, hubs, rims, and the rest.

One thing that's happened since I've started building this bike is that the Berlin Wall fell. So, seriously. Velocity has started selling 130mm disc rear hubs. Up until now, the only option I've been able to find for rear disc hubs spaced 130mm is the real expensive ones like Chris King or Hope. But the Velocity hubs sell for $99 apiece -- more than I'd like to spend, but bearable. I've got a couple: one will go on this bike, and the other will go on Carol's.

As usual, I'm building up on Alex DM18 rims, 32h (I believe the Veolicity hubs are only available with 32h; otherwise, I'd use 36h for myself) using Sapim 14g straight gauge spokes.


Chad Richmond said...

Maybe we'll see you at the next race!

Ted Diamond said...

Yeah -- ringing' the cowbell!!

Ted Diamond said...

I've been hearing a bit of grinding from the disc brake. It doesn't coincide with the rotation of the front wheel, but with the rotation of the crank. Turns out the front hub (DMR Revolver) has a bit of play, so I'm guessing that's making the plane of the rotor vary with respect to the plane of the caliper's pads.

Nic Pottier said...

This is pretty much a given on disc brakes.. they always rub a teeny bit. The good news is that a teeny bit doesn't equate to any loss of speed.

Does really get into your head when you are on an endless singletrack climb though and all you can focus on is that squeak.

Ted Diamond said...

Yeah, the grinding makes it hard to hear the voices in my head.

Ted Diamond said...

Well, everything went great with the rear wheel for 3 months. I gave it a battering on the broken roads, railroad tracks, and pitted gravel alleys of Sodo, loaded down with a computer and often loads of library books.

Over the course of the last week, I broke 3 drive side spokes, right at the head (leaving the bend intact).

And discovered that with disc wheels, you may have to remove the rotor to change a spoke!

Back to the drawing board