Tuesday, March 18, 2008

Equipment - DV46 Clinchers

Last winter, before I became a full time cyclist, I sold off a bunch of wheels to finance the purchase of some Reynolds DV46Cs - 46 mm carbon rimmed clincher wheels. They are a virtual twin to the DV46Ts I race on - just the clincher's "more white" decals alert users that I don't have the tubulars.

I got them for a bunch of reasons. The last one is that they are really cool looking. There's something about the image of a deep carbon wheel spinning in one direction, cranks (with the chain on the big ring) spinning the other direction. It screams speed, of fast, of exhilaration.

Imagine someone hammering on this bike, wheel spinning one way past the chainstay, cranks the other. Screams speed, fast, exhilaration, doesn't it?

And, thanks to the Cervelo and Zipp marketing gods, it also reminds me of CSC.

Anyway, the last reason is the least justifiable. It doesn't win budget conversations with the missus ("But honey, these wheels just scream speed, fast, exhilaration... they look so fast. Hello? You got that glazed look on your face again. Am I doing it again?").

I like my bike a lot.

More logical reasons trump cool, fast, exhilaration. I'll list some below.

1. I race on DV46Ts. The wheels feel so different (super light, super fast, different rim profile compared to any non-Reynolds wheelset I own) from any other wheel I had that I would spend a few miles getting used to the wheels. On race day I tend to warm up very little so some of those miles getting used to the wheels occur during the race. You know, while elbow to elbow with 80 or 100 of my closest (in a physical sense) bike racing friends.

This procedure is best described as "Not Ideal".

Riding similar wheels (the DV46C is about as close as you get) would let me get used to the wheels when training. Lo and behold it has. No more weird brake action from yours truly in the first few laps of a race, no more swerving a bit in turns, just the standard "just riding along" stuff.

2. I used to use the same standard brake pads for my aluminum training rims and the DV46Ts. I realize this isn't ideal but I don't feel like swapping pads before each race, changing how the bike feels etc. I didn't want to ruin my DV46Ts by scraping holes through the sidewalls so I decided that I should use the carbon specific pads. But I didn't want to swap the pads all the time so it was either get new race wheels or get new training wheels.

I got new training wheels.

With the DV46Cs I put carbon specific Swiss Stop pads on full time and am now used to the way they brake, feather, etc. There's no surprises when braking on race day like there was before.

3. Since the wheels have the same hubs (I made sure I was buying the same generation of wheel, with the non DT hubs - White Industries I think), there is no need for any fine adjustment when swapping between wheels. Not the case with some of my other wheels.

4. Since the wheels are both nice, the clinchers are a good wheel pit wheel set for the tubulars. Nothing wrong with racing the DV46Cs.

5. I have faith that the wheels will get me home when I go training on them. I popped a spoke in the DV46T front wheel about 10 miles into a 30+ mile circuit race (Prospect Park) and felt fine finishing the race with 50+ mph descents, tight fields, and a massive field sprint, all on a 15 spoke front wheel. I think I got 6th in the wild sprint (which reminds me, I still have a helmet cam clip to finish up - of that race), spoke twanging on the fork the whole time. If the tubular wheel made it through that, I figure I'll be able to get home if the same thing happens on my clinchers.

My stats and riding habits, for comparison sake:

1. I weigh about 170-175 now, topped out at 190+, min will probably be 165 (that was my minimum in the last 10 years or so). I ride a SystemSix pretty much exclusively at this point so not some super flexy frame. I usually carry a small seat bag (very densely packed - weighs about 2-3 pounds), 1-2 bottles, and a mini pump. I don't really load the bike up too much. Anymore stuff I put in my pockets - in other words, when I hit bumps, that stuff normally unweights along with me.

2. I bunny hop everything that significantly threaten my wheels, unweight when riding over normal bumps, and tend not to run into deep potholes and stuff. The last time I pinch flatted a clincher was when I double flatted at 45 mph drafting a truck, maybe in 2004. The rims were unbent. It might have been my panicked hop but I doubt it - the tires blew. It's probably just some luck. I'm pretty sure the last rim I bent bent was in the mid 90s.

What I'm trying to say is that I tend to be easy on rims.

3. I ride 23c tires (Krylions, excellent tire for everything a Cat 3 would do), am religious about checking pressure, and typically run them at 105/110 to 115/120 psi (front/rear). I don't neglect my tires and I don't run stupid narrow tires.

4. I train both indoors and outdoors on the DV46Cs. My rides are anywhere from 30-45 minutes up to 6-7 hours long. Typical rides are 1-3 hours long.

I do have some DV46C dislikes:

1. At 50+ mph on descents with gusty wind (i.e. either gusty wind or a passing truck a few feet off my elbow) the front DV46C gets a bit unstable. I'd prefer a box section front wheel for situations like that and I'll be building one up (aluminum) for those times I may want something more stable.

When I say "unstable" I don't mean "crashingly unstable". I mean I feel the need to get out of my "hands next to stem" tuck and get into a "hands on drops" tuck. I also lean over a bit less - my underside of my chin isn't about to be burned by the tire (it's happened before). With a box section front wheel I feel comfy at 55-60+ mph, chin hovering over tire, hands by stem.

2. I don't like the bladed spokes. The wheel swerves a bit when sprinting. I switched the tubular to round spokes (2.0 DT Revolutions) and it made a huge difference. I am waiting to pop a spoke on the clinchers and then I'll do the same.

I bought the DV46Ts new, the DV46Cs used. Used, Campy freehub wheels like mine are typically sold at $850-900/pair on eBay in good shape, with tires, cassette. Figure $150-200 less for tubulars. I admit I paid on the high side for the clinchers but they included spiffy tires, tubes, a titanium cassette, and some wheel bags.
I'm pretty sure the wheels weigh about the same, but with a training cassette on the clinchers (all steel 11-25, versus a half titanium 11-23), clincher tires/tubes (about 200 grams or 1/2 pound heavier), I figured there should be a slight difference in weight. I confirmed this by weighing the bike with the tubulars fitted first and then the clinchers fitted next. The latter give up about three quarters of a pound penalty, so not very much. With the clinchers the bike weighs in at about 16.5 pounds, about 15.75 pounds with the tubulars. Not illegally light but nothing to complain about.

The tubulars are in front. Note the two different colors in the cassette - the bigger cogs are titanium. Also note the brighter decals on the clinchers -more white and silver make the decals much brighter.

Both sets of wheels. The clinchers are on the bike. The front tubular has silver round spokes. The rest of the wheels have the stock black spokes (round on driveside rear, otherwise bladed).

Incidentally my previous bike, with the identical DV46Ts (including cassette, skewers, and tires) on, weighed 17.5 pounds. It feels noticeably heavier than the SystemSix.
Because I now know it takes a few minutes to swap pads, I'm not as concerned about mixing up my wheels with aluminum rimmed ones as I was before. Changing between aluminum and carbon rims doesn't faze me now. I simply don't have a race wheel set up at this time. Plenty of training wheels but no nice, light, 28H tubulars ready to go.

A final note. It might be my imagination, or it might be that I'm just used to aero wheels, but these wheels, they don't seem that aero. They seem more like the old Zipp 340s I had - light, super quick acceleration, but they top out quicker than more aerodynamic wheels. I don't know, I don't have any data on this.

Plus it's still cold out, and that makes it worse. I ride with a jacket on top of everything else every time I go out. It feels a bit constrictive and not as fast, so I don't like doing max speed efforts at this time. So my top speed efforts are a bit misleading. And finally, right now, without any speed measuring devices on the bike, I can't measure anything anyway.

So much the better, that's what I think.

I'm just waiting for the warm days to hit. And then it'll be time to go out and play.

4 comments:

Anonymous said...

aki-
just be careful on descents with carbon clinchers. Not sure if it is was just something the Zipp rep. told us so we would sell his wheels but there have been cases where people ride the brakes on descents and the carbon/resin heats up to 400o and blows the tires since the rim expands at that type of heat/ the air pressure significantly increases with that type of heat. He also mentioned that the braking surface may glaze because the resin is set at 300o (these are the reasons Zipp has no plans to make carbon clinchers). Then again, he said these blowouts happened down alpine decents which we are short on around here...

Anonymous said...

Love you bike Aki - especially the SRM. I race on Bontrager Aeolus/HED 65s. Super Aero and fast. Once you ride a set of deep dish tubulars there is no going back.

Jesse G - theBell-lap.com

Anonymous said...

man how do you afford all this shit and ride full time?

Aki said...

Sam - I was wondering where the heat went when I braked on these things. Apparently there are some brake pads that absorb enough heat and transfer it to the brake shoe holders. I did go down a 30+ minute descent full of hairpins (Palomar Mountain, all the way down 14-15 miles worth) without too much problem.

Jesse - love the bike too :) SRM is currently being refitted with a battery so the cranks are just really expensive cranks for now. I'm itching to get some more aero wheels but they'll have to wait.

Anon2 - I bought pretty much all the stuff before I "started riding full time". And the way I've lived the last 10+ years, I am free and clear (ditto the missus). We lived well within our means. When I buy something, it's paid for before the due date on the credit card bill.

Plus I'm sort of a cheapskate, I think about things for months and years, I'm easy on equipment, maintain it, and I rarely buy new stuff. When I do I hang onto it for a long, long time.

It helps that I can do everything related to assembling a bike - build wheels to replace tubes - so it's not a big deal for me to say relace a wheel with new spokes (makes for reliable wheels). I tend not to buy into new technology until I think it'll work.

For "new" aero wheels I mention to Jesse, I'll probably glue some tires on my TriSpokes (now known as HED3s) - which I bought more than 10 years ago. And I'll rebuild my Zipp 440 as a rear wheel (maybe for my track bike) - and that's a rim I bought maybe 12-13 years ago.

I was once poor - check out my post on "Bike Race vs Life Race". Also check out my Karma post.

I can tell you that I don't know of many rich bike racers but there are a lot of people making a lot of money doing other things. If you live within your means, work your way through things with your career, you'll be fine.

I'm trying to get my third career off the ground now. First was bicycles (15 years), second was IT (10 years). The third, if it works, I'll post about it :)