A tale of two road bikes.

I’ve been spending a lot of time on the Trek 770 of late, after spending a lot of time on my Madone this summer.  I’m amazed by how quick handling the 770 feels, and had initially planned on writing this blog post about the huge differences that happen in bike geometry over the course of 25 years.  In all honesty, the 770 was the pinnacle of Trek road bikes in 1985, and the Madone 7 is the pinnacle of today, so it’s apples to apples, even though one is lugged steel and the other is carbon-fiber.

I got out the tape measure and started doing some measurement.  Much to my amazement, the wheelbase on the two bikes is within 1/2cm.  In fact, if you slide the wheels in the dropouts on the 770, the wheelbase is identical.  Rather shockingly, the chain stay length is also within a hair, to my tape measure.  According to their published specs,

The Madone has a 52.5cm seat tube length; the 770 is 54.9cm.

The Madone has 4.5cm of fork offset; the 770 is 3.8cm.

The Madone has a 99.3cm wheelbase; the 770 has a 97.1cm wheelbase (at the shortest setting.  When pushed back in the dropouts, the wheelbase is about identical).

The Madone has a 56.4cm “effective” top tube length; the 770 is 55.5cm.

The Madone has a 40.7cm chain stay length; the 770 is 41.2cm.

The Madone has 7cm of bottom bracket drop; the 770 is 7.2cm.

The Madone has a 73.5 degree head tube angle; the 770 is identical.

Accordingly, the top tube on the 770 is a bit higher than on the Madone, which throws some of the measurements (such as seat tube length, etc.) off a bit, but the geometry is pretty remarkably similar.

I’ve come to appreciate that the 15% reduction in fork offset, coupled with super-narrow, skinny handlebars, is likely what makes the 770 feel so much more lively/nervous (depending on whether you want a compliment or a pejorative).  (If you want a better explanation of fork offset and its significance, click-through to this older post about the Vaya).

Nonetheless, I’m amazed at how close the geometry on the two bikes is, notwithstanding the 2.5 decades between their construction, not to mention their different materials.

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Stans ZTR Rapid Wheelset

With the ENVEs replacing the Crests on the Vaya, the Crests were sitting on my shelf without a home…

So I slapped a Surly singlespeed adapter set on the cassette, along with a pile of SS cogs I had laying around…

And threw ‘em on the El Mariachi.

In garage poseur shots, they look great.

That brings up the ZTR Rapids that came stock on the El Mar.  There’s not a lot of info out there on them, so here’s a bit of data.  This is the stock build for these wheels, from Salsa, with SS hubs and lordknowswhat spokes.

Rear wheel, stripped, weighs…

1246 grams.

Front wheel, stripped, weighs 918 grams.

Make appropriate adjustments for your hubs and spokes…they aren’t light.  They are reasonably stiff, and set up tubeless well.  They do have the spoke eyelets that reduce manufacturing cost (making these more friendly for OEM specifications), but they’re not light.  (Note that all of the weights in this post are comparing the wheelsets set up for tubeless, with Stan’s rim strips and such).

By comparison, the DT240/CX-Ray/Stan’s Crest wheelset that replaced them on the El Mar is just under 200 grams lighter up front, and 420 grams lighter in the rear.  That’s about 1.4 pounds of rolling weight.

The Crests are 24.4mm wide with an ID of 21; the Rapid Rims are 25mm wide with an ID of 21.  Both share a common depth of 15.8mm.  According to Stans, the 29er Rapid Rims weigh 455 grams, versus 380 for the Crests.  Frankly, I have a hard time believing that…I’m guessing the ZTR Rapids are closer to 500 grams than 450.

That means that the DT240/CX-Rays save 130 grams over the stock build up front, and 350 grams over the stock build in the rear.  Re-donk-ulous.

Again, the El Mar isn’t a light bike, and I have not set out to make it a weight weenie.  Even with the Crests, it almost certainly weighs more than the full-suspension Superfish.  But I had the Crests, and they needed a good home.  Annnnnnd….if you’re going to do an upgrade, wheels are the place to start.

I had a chance to put about 15 miles on the Crests Saturday morning, predominantly doubletrack, doing a lot of climbing and a little gravel.  They spin up fast.  Appreciably lighter than the Rapids.  In theory, the Crests should be less rigid than the Rapids, because of the use of a SS hub on the Rapids (wider spread of the spokes) and the use of a cassette-friendly hub on the Crests (because they were moved over from the Vaya, and I didn’t see a point in relacing to a SS hub).  Perhaps because I’m a lighter rider, theory didn’t play out–I couldn’t notice any reduction in stiffness.  If anything, the Crests seemed to have more pop and more responsiveness.

I was playing around with tire pressures running the Continental 2.2″ Trail Kings (tubeless), and got down to 15 before things got too squirrely.  I think I might run 18 rear, 20 front, and see how that goes (just because I’m a bit nervous about peeling a bead on the front).

Anyone need some gold SS hub’d Rapid Rims?  They’re tubeless!

The Penultimate Vaytanium

The Vaytanium just got an upgrade.

I’ll have full weights and details in the next few days.  I’m still (very happily) running my 38c Bontrager CX0 team issue tires.  As per my normal practice, these are DT240 hubs and Sapim CX-Ray bladed spokes, with ENVE nipples, built by Chad at North Central Cyclery.

I threw them on the Vaya Wednesday afternoon, in anticipation of the group ride that night.  27 miles Wednesday, and 50 miles yesterday lead me to some preliminary conclusions:

1.  On pavement, I cannot tell a difference between the Stans Crest and the ENVEs, in terms of ride quality.

2.  On gravel, I am pretty solidly convinced that if you blindfolded me and had me ride them back to back, I could discern between the Crests and the ENVEs–partly from the noise, and partly from the ride quality differences.  The difference is subtle, but palpable.  It certanly isn’t anything like the huge jump from my old wheelset (Chris King hubs, stainless spokes, Velocity A23s, tubed) to the Crests.

3.  I can’t tell if this is real or not, but I feel like there’s a bit of a change in the aerodynamics of the wheels  These are not really an aero profile, but they feel faster at higher speeds, as compared to the Crests.  Truth be told, some of that may be attributable to the feeling of spending a lot more time on the Vaya of late, after a winter of fat biking…but I made a transition directly from Crest to ENVE, and I feel a difference above 20mph.

4.  I’ll have full weights and such later, but of note, there’s not really a weight advantage on the ENVE 29XC clinchers, compared to the Crests.  Both are stupid-light.

5.  Why the Penultimate Vaya?  Because it’s still waiting on hydraulic disc brakes.  The Ultimate Vaytanium will be this bike, plus SRAM Red 22 with full hydros.  Oh please oh please oh please.

Gore, Knog, Fatbikes, Local Bike Shops.

These are a few of my favorite things.

Thursday night was the Winter Clinic at North Central Cyclery.  It was a night of bliss for the author of this particular blog.  Why?  Soooo Muuuuch Gooooodness.

Demo Beargrease (like the one I rode a couple of months ago, also at NCC).

Demo Krampus.

Krampii.

Brand-spankin-new Ti Warbird.

Delectable S’mores made from energy waffles endorsed by now besmirched cyclist formerly known as ’7 time tour winner.’

They were so energy packed, that Chad came in clean-shaven, had one bite, and instantly grew a beard.

And there was Peter.

PBR.  Like a moth to a flame, I tell ya…

There was a dinglespeed TI Muk wearing Big Fat Larry’s on 82mm rims.  I took these pics to show that there’s plenty of room for Lou’s in the rear.

And there were oodles and oodles of people.  Over 60, not including the sponsors.  For a winter-riding clinic, that’s pretty exceptional.

Lots of cool products to ogle…like the entire line of Gore clothes.

Wolvhammers

An array of Knog’s latest and greatest lights, including a couple of models with nifty features like USB recharging.

Mattias found something pretty in pink…

And then decided to find out whether Gore-Tex is really waterproof or not.

It is.

No, really.

GoreTex Works–North Central Cyclery Gore Demo 11.1.12 from Lawfarm on Vimeo.

Not kidding.

And lest you think that pink was the only questionable clothing choice of the evening…

Yeah.  There’s that, too.  The belt really completes the outfit.

BPaul tried on approximately 435 coats.  I’m pretty sure he ruled out at least 3 or 4, and he’ll probably settle on a final choice right around the time the national debt gets paid off.

In the realm of demo bikes to ride, they had the aforementioned Beargrease and Krampii, and a host of fatbikes from XL Pugs, Neck Romancers, Moonlanders and Mukluks, all the way down to a 14″ Pugsley.  You can’t help but smile.

Beth…you really need that bike.  It is sooooo you.

And if you had questions, they could be answered by none other than Salsa’s own E-Fred:

Or you could hear about how the fuzzy lining on the inside of Windstopper is made from the hair of shaved, free-range Unicorns from Brendan Gore-Cik.

Or maybe you have a light question for Knog’s Brian Mark…

So yeah, a night full of awesome.  New products to ogle, information to learn, things to see, things to try.  I can’t convey all of the information received, but here are a few Gore highlights:

The gore membrane used in Windstopper and Goretex are related fabrics.  The Windstopper is a bit more porous, but still waterproof.  Windstopper doesn’t have taped seams, so they don’t market it as waterproof…and it’s more breathable than straight Goretex.

They had a demo where you’d get your hand wet, and stick your wet hand in a goretex gloveliner.  You’d then put your wet hand, in the glove, in a bucket of water.  You would then move your hand around vigorously.

I kid you not…when you pulled your hand out, it was dry.  I wouldn’t believe it if I didn’t see it.

Seriously.  Moving your hand generated heat, which turned the water on your hand into vapor, and the Goretex transferred that vapor away from your hand, directly into a bucket of water.  Ridiculous.

Brendan used a great metaphor for Goretex…he said it’s like a chain link fence.  On the outside, water is the size of a softball, and thus cannot get through the fence.  But on the inside, sweat vapor is smaller, like a golfball, and can pass through the fence.  Makes sense, and was a great analogy to consider.

I kind of feel like I’m rambling right now, but there was so much information to learn and absorb.  It was truly a great evening.  I ride outside a lot, and have read a ton about Gore clothes…turns out, I haven’t scratched the surface.

I cannot emphasize enough how awesome it is to have a local bike shop able to pull together events like this, and get experts and information like this.

 

 

 

 

 

Two Wheel Drive Fatbike?

CJBrubaker on MTBR recently posted up his 2wd Fatbike.

Here’s the bike (with a nice Lefty setup), pre-conversion.

And here it is, post-motor conversion.

He’s running either Big Fat Larry’s (for general use and sand) or Nates (for snow or mud), on the 100mm rims.  The front hub motor is a Nine Continents 2808 mounted to a Choppers US 100mm, 36h rim.  He reports that he’s using the same 36V battery that he uses with a Stoke Monkey on his Big Dummy.  With that setup, the motor has enough power to spin the front tire in the snow…apparently, moderation is required with application of the front motor power.

That’s a lot of extra weight, but it’s an intriguing thought.  If Surly ever gets around to Big Fat Nates…..a set of BFNs…at 6psi…with 2wd power…means that just about no snow could stop you.

De Main Domane Bearing

I’ve had a couple questions sent to me about whether the Domane actually has a pivot point in the seatpost, or whether it just has an elastomer to isolate the seatpost from the seat stays and top tube.

It has a pivot point.

Pic from cxwrench on RBR.

There are 2 bearings; both are 19mm outside diameter, 10mm inside diameter, 5mm wide.  Both are sealed.  The seatpost flexes on a pin through those bearings (the bearings being located in the top tube/seatstay junction).  There is also elastomer in the joint to help control flex and keep vibration down.

And yes…when you push down forcefully on the saddle, the top of the seat tube flexes back, and the ‘middle’ of the seat tube (between the bb and top tube) flexes forward.  If you watch that bottle cage, you can see it move forward in response to the flex.

That’s all.  Carry on.

BILTO: Manbearpig

BILTO = Bikes I’d Like To Own.  That’s a new RATG acronym.  We’re big on acronyms here.

Today’s BILTO is a bike that appeals to me on some very basic level.  Since I have the Vaytanium, I’m not building up this bike.  But if I didn’t have the Vaytanium…

I find this build intriguing because: 1) it’s a collection of nice components; and, 2) it shows how incredibly versatile Salsa bikes are.  This particular La Cruz happens to be a steel frame.

The Manbearpig is stolen from MTBR, where it was posted by rroeder.  (And by stolen, I mean fair use.)  Pics:

Uhh…wait a minute…

That’s better.

Build Specs that I can discern from the pics:

La Cruz (steel)

SRAM X7 Rear derailleur, Shimano 105 Front derailleur.  SRAM Brifters (look like Rival, perhaps?)

Stan’s ZTR Arch.  Looks like Schwalbe Smart Sams (maybe 700 x 40c?  Or are they 29×1.75?)

Thomson seatpost and stem.

Not sure what bars (perhaps Salsa Bell Lap?)  Man, those brifters are waaaay up there in the mounting.  Probably for single track controllability.

Anyhow…it’s a nice build spec–reasonable budget for a highly functional bike.  It’s probably equally at home on single track, doubletrack, cross, gravel…maybe even light touring.  The owner indicates that it’s “1/2 cross, 1/2 mtb, 1/2 graveler.”  Sounds about right–that would mean 150% awesome.  Manbearpig…it’s a BILTO.