Saturday, July 07, 2007

Equipment - Power Tap Wheel, Part 2

The last day or two I've been thinking about my PT wheel rebuild project.

I optimistically chose normal shipping for the 380 gram Mavic rim (I ordered it online as the local shop I patronized is closed for the moment). Problem is that it wasn't scheduled to show up until Monday.

Not good for a Sunday race.

So I thought about rim things. Made notes on my daily meeting agenda printout. Put miscellaneous notes into my (Windows) phone. Hemmed and hawed. And finally I bought another rim. When I checked it out I learned that it is a bit heavy. Of course I learn this after the fact. Great for Paris Roubaix. Not the rim I want for a criterium.

I guess if I ever do 'cross, I have the tubular rims for whatever bike I get.

With the (not 'cross) race rapidly approaching I had to look at what I already own.

I reassessed my wheel inventory, looking for any reasonable weight 32 hole tubular rim. I found a few other other 32 hole tubular rimmed wheels. I have a few so I checked some weights online as I thought they were light - but they weren't, most of them 400 grams or more. I do have a few low (or sub) 300 gram rims but they're all 28 hole - can't use that with my 32 hole PowerTap hub.

You know that SRM is looking mighty appealing - just slap my fave Reynolds wheels on and go...

Then I looked at my track bike. It's supremely overbuilt - a 7 pound frame and fork (staight gauge steel), 32 hole Superbe Pro track hub, 14 gauge straight spokes in the rear, brass nipples, and...

A 32 hole Sun M17A tubular rim.

330 grams or so. No eyelets but I have DT washers for such a rim (0.1 grams each washer). 17 millimeters wide. And I have a brand new 18 mm tubular tire glued to it. Already stretched, already aged, already pressure tested.

Not the best training setup. Wouldn't corner too well either. But man it would fly in a race. And New Britain (and the two Prospects right after) are all on kidney shaped courses - no real turns.

So I'd unlace the track wheel, pull the rim, save the hub. Said rim would be built into a wheel around the PowerTap hub with some nice DT Revolution spokes, alloy nipples, and the DT washers for non-eyeletted rims for durability.

That would leave me with the track hub and a track bike with no rear wheel. With only one track wheel to my name, that'd leave me without a track bike (not that I've raced on the track since 1991 or so but that's a different story altogether). I figured that it'd be a perfect excuse to lace up a 24 hole Zipp 440 to the 32 hole track hub as the track hub is a lot more tolerant of odd spoke patterns than my PT hub. The track hub doesn't care if the spoke count is consistent left-right or if there are crosses or not.

Since I have very few races left this year, I may build the PowerTap M17A wheel to use just for the next month or so. Then rebuild the wheel using a normal clincher rim.

Or maybe find a 28 hole PowerTap hub and do up one of my 300 gram tubular rims on that. Hm. House stuff may take precedence over that. Whatever, I can revisit later.

I figured that I'd quickly pull the M17A rim, quickly unlace the PT hub. Quickly because we were going to my dad's last night. I would bring the stuff to lace and true the wheel to my dad's house where we're having a continuation of our July 4th family get together.

I hoped that when I got home, I'll be holding a new M17A PT wheel complete with a newly glued Conti tubular.

I wrote all that stuff and then guess what? The Mavic rim came in. So I brought that to my dad's, laced it up while everyone played cards, glued on a nice new CX, and brought it home.

So today I'll be testing my new Mavic rear wheel and see how it goes. It feels heavy when I pick it up so I'm not sure I'm too keen on it. It's the same rim used in the discontinued Heliums - the Mavic wheels I thought were so slow I abandoned them after one race.

So tomorrow if you see me on my Reynolds rear wheel, well, you'll know how it went.

1 comment:

Anonymous said...

Are those Record Crono rims up to road racing or cross with modern hubs and high dish? David