Friday, August 1, 2008
for high-end road bikes that it claims will vastly improve performance and
reduce maintenance. By replacing the conventional levers that pull wound-steel
cables through protective housings with solid-state switches and rubber-coated
wires, there's no chance for road gunk to clog things up and interfere with
shifting, or, for that matter, your post-ride beer.
The principle of an electronically controlled drive train is to execute
perfect shifts every time, thus "reducing mental overhead," in the words of
Shimano marketing manager Devin Walton. This is a resource cyclists find in
short supply during epic rides.
Thursday's announcement that the system, called Di2, will hit shops in
January 2009 settles a question first raised in 2005 when prototypes began
cropping up on the bikes of select Shimano-sponsored racers in the pro
peloton. The system's development has been photographed, chronicled and
Angsted over ever since.
But if the existence of electronic shifting comes as no surprise, its
weigh-in certainly should. During a recent telephone interview, an industry
insider who spoke on condition of anonymity stopped cold amid a
why-do-we-need-this diatribe, upon learning that Di2 weighs less than
Shimano's current generation of parts. According to the company, Di2 will be 67
grams lighter than the current
Dura-Ace 7800 and only 68 grams heavier than Dura-Ace 7900, the snazzy
forthcoming 2009 suite of parts. "I'll be going to hell," said the source, who
then fell silent -- no doubt converting grams to ounces to fractions of a pound
to the limitless advantages of such weight savings. That's at least an extra
Shimano plans to offer the electronic setup as an upgrade option within the
7900 group -- which is preselling for $2,600 -- so parts such as the two-tone
cranks and brakes will be the same. (No word yet on the additional cost for
electric; it could be double.) Di2 consists of two brake-and-shift levers, two
derailleurs whose springs have been replaced by servo-motors, a 7.4-volt
lithium-ion battery pack, and the wiring harness that connects everything.
The derailleurs, whose job is to move the chain from gear to gear as you
shift, talk to each other and automatically adjust so the chain doesn't rub.
They also calibrate themselves, so you don't have to play with cable tension to
maintain shift quality as cables stretch and the chain and cogs wear. And
although the control buttons have been placed in the traditional location behind
the brake levers -- so as not to confuse anyone or overly tax that mental
overhead -- they could be integrated with the ends of time-trial bars, the top
of the handlebars or just about anywhere a rider might find convenient.
Still, the advantage that people who've experienced the system talk about is
how little effort it takes to change gears. A quick nudge to one of the shift
switches signals a motorized worm gear in the derailleur to instantly move the
precise amount it needs to. Fractions of a second later, the chain snaps into
Chris d'Aluisio, director of advanced research and development for
Specialized, likens the difference between mechanical and electric shifting to
the difference between driving a race car with a manual transmission and one
with F-1 style paddle shifters. "You can stay on the gas and flip through the
gears with no hesitation," said d'Aluisio. "It's seamless power."
Frankie Andreu, who raced in nine Tours de France, described the shifting as
"immediate and very smooth and accurate.... It's super nice."
Even my curmudgeonly unidentified source said, "The shifting is mind-blowing:
I mean, you just touch the button, and it shifts."
But let's not lose perspective. Shimano isn't the first company to attempt
electronic shifting. Mavic introduced
Zap in 1994 and then a wireless version called Mektronic in 2000, neither of
which survived. Zap's wires proved to be less than waterproof, and Mektronic was
finicky to set up properly. Shimano, notorious for its rigorous testing
gauntlet, is betting that its engineers have solved the electricity problem --
and so is Campagnolo, a competitor that is on a similar development path but has
yet to announce when it will release its system.
The crux of the engineering challenge is making the battery light yet
long-lasting, so Shimano's engineers turned to the hardest-working part in any
shifting system: the front derailleur. It's also the most temperamental, with a
nasty habit of dropping or jamming the chain if the rider doesn't modulate his
tempo properly while shifting. (Mavic didn't even go there -- only the rear was
electric.) To be fair, the front derailleur has the notably tough job of moving
a chain under heavy load between two gears of dramatically different sizes,
moving at different speeds. The Di2 crew knew going in that it would require
three or four times the juice of the rear derailleur.
So, when Shimano started out in 2003, the initial strategy was to throw a
bunch of power at the problem, and take advantage of the servo-motor's massive
torque. But this came at too high a cost, according to former Olympian Wayne
Stetina, a Shimano vice president whose primary job is to test equipment and
provide feedback to the engineers in Japan. "As I recall, in 2004 we had a much
larger battery that went dead on me several times during long rides," said
Stetina, who has logged 19,000 miles on various iterations of Di2. "It couldn't
last more than three or four hours between charges, and the battery pack and
control system weighed nearly a pound."
That wasn't going to fly in a sport where grams can translate directly into
seconds. The trick would be to conserve power, not squander it. Shimano's
engineers redesigned the geometry of the front-derailleur to amplify the force,
so they could get the necessary output with far less input. The greater leverage
of the new derailleur allowed for a much smaller battery and ultimately shaved
half a pound off the system. Stetina claims the battery consistently lasts 2,000
miles between charges (which takes 90 minutes). Officially, Shimano says the
battery will last for 1,000 kilometers (621 miles).
The front derailleur doesn't actually move with more force or more speed, as
you might assume. It does receive the signal to shift faster than you can send
one by cranking on your lever and fighting against friction, spring tension and
a lesser mechanical advantage. More important, it should do the same exact
thing, every time, without needing to be coaxed or cursed. Powered as it is by
an electric motor, the front derailleur simply moves a calibrated distance when
it's told. "It just jams the chain into the big ring, no matter how much load is
on it," d'Aluisio said. "You don't lose any momentum, and your legs never
Road-bike aficionados are much like trout: simultaneously enthralled and
mortified by anything shiny and new that enters their environment. And so it's
not surprising that the first two questions people tend to ask about Di2 are: 1)
What if the battery dies? and 2) What if it gets wet?
Stetina believes he's personally answered the first. And besides, he said,
there is a battery meter on the Flight Deck computer (which includes heart rate,
altimeter, inclinometer, calorie counter and the ability to download all these
details to your PC after the ride). His unscientific-though-admirable strategy
for testing the waterproofness of the system has been to blast the components
with the high-pressure hose at a coin-op car wash.
Presumably Shimano's engineers in Japan have more-traditional testing
methods. The company prides itself on systems engineering, and has been working
on this set of components for more than five years. How will it work? You can
find out for yourself when Di2 goes on sale in January. Call us when you've put
12,000 miles on it
Friday, July 18, 2008
There new Ultremo R will be a scant 180g with better puncture resistance. Also a "DD"
(Double Defense) model with be available.
Ultremo R will be available in colors as well. These will be available @ sales.light-bikes.com this August!
**Ultremo R - New Triple Nano Compound which reduces rolling resistance. A new HD Ceramic layer with improved puncture protection, 127 tpi
**Ultremo DD - (Double Defense=HD Ceramic Guard + Snake Skin) with stronger sidewalls and +/- 30 grams more than a Ultremo R version and 67 tpi.
Ultremo R will be available in many colors-
Wednesday, June 18, 2008
Tuesday, June 17, 2008
Wednesday, June 11, 2008
Sunday, June 1, 2008
Larger version: http://light-bikes.com/BikePhotos/web_pics/DA7900big.jpg
FC-7900 Dura-Ace crankset
The new Dura-Ace crankset features a hollow outer chainring. Likely due to the ring and further refinement of its hollow forging process Shimano claims the crankset is 20 percent stiffer and 15 grams lighter than the 7800 edition. Other changes include redesigned chainring teeth said to improve chain interface and power transfer, as well as improved bottom bracket seals to reduce contamination and friction. The new crankset does not adopt Shimano’s 970 XTR non-drive crank arm attachment; instead it retains the pinch-bolt style design of the old crank.
After a long wait Shimano will also carry a Dura-Ace branded compact crankset (34/50) with the 7900 series group.
The latest word of Shimano’s yet-to-be-sold Carbon Dura-Ace crank is that it will keep the 7800 series designation and chainring style. Its revised release date is later this year, likely fall.
FD-7900 Dura-Ace front derailleur
Shimano claims its new Dura-Ace front derailleur cage design eliminates the need to manually trim the front shifting, therefore the extra detents have been eliminated. The redesigned front derailleur linkage is wider and the spring is tweaked to reduce the effort required at the shift lever. This is a tough one to stomach, as the absence of trim for both chainrings is one of our top gripes when it comes to SRAM’s road groups.
RD-7900 Dura-Ace rear derailleur
The rear derailleur further illustrates the brand’s acceptance of carbon fiber with a carbon fiber pulley cage. The rear derailleur loses another 16 grams. The new mech is compatible with wider range cogsets and can accommodate up to a 28-tooth cog.
ST-7900 Dura-Ace Dual Control levers
The new STI Dual Control levers offer a refined ergonomic shape and are claimed to be 40 grams lighter. 7900 will be known as the group in which Shimano fully accepted carbon fiber. The new STI levers feature unidirectional carbon fiber lever blades, which are responsible for much of the reduced weight. Shimano also took the opportunity of a lever redesign to tuck both the brake and shifter cables under the handlebar tape, putting it in line with its competitors. The shifters are held to bars via titanium clamps and bolts. Shimano claims that the revised internal mechanism along with a new PTFE-lined casing keep the action as light as previous designs.
The shift stroke for the rear derailleur has been reduced by 20 percent for quicker shifts, but a 7800 rear derailleur will work with the new group and vice versa. A built in reach adjuster allows for fine-tuning the fit for riders with smaller hands.
The shifters continue to offer integrated controls for a new FlightDeck computer (SC-7900), which has been updated to include heart rate, altitude, grade, cadence, gear position, and is directly downloadable via a wireless connection. The new SC-7900 computer is completely wireless via the use of a coded frequency.
BR-7900 Dura-Ace brakes
According to Shimano its new Dura-Ace brakes have “Increased linear response, improved braking power and reduced weight.” In addition the company claims that its new brake pad compound doubles wet condition performance, while improving dry power by 20 percent. If this proves true, Shimano will have a brake that’s untouchable in terms of power; the current version still serves as the industry’s benchmark. The “increased linear response” is spawned from a redesigned caliper arch, while the cable stop is lower profile, creating smoother cable routing, which is said to reduce cable friction. The brakes feature a spring tension adjuster and adjustable toe-in for the pads while dropping nearly 30 grams from the combined front and rear calipers.
CS-7900 Dura-Ace cassette
Shimano claims further shifting improvements by creating a stiffer and lighter aluminum carrier along with re-engineered tooth profiles. The largest four cogs are titanium. Shimano claims the cassette is 10 grams lighter. The 7900 Dura-Ace cassette will be available in the following combinations: 11-21, 11-23, 11-25, 11-27, 11-28, 12-23, 12-25 and 12-27.
|Components||Dura-Ace 7800 Weight (Grams)||7800 (2008) Pricing||Dura-Ace 7900 Weight|
|Chain (116 links)||280||$50||262|
|Rear Hub 7850||267||N/A||N/A|
|Weight w/out Hubs:||2181||2052|
(2009 Dura-Ace 7900 pricing is not available)
Thursday, May 29, 2008
Wednesday, May 21, 2008
Super Record, Record and Chorus will now be 11 speed.
None of the 11 speed stuff is backwards compatible either!
The chain has been reduced to 5.5mm, and the 11 sprockets fit in the same space that 10 once did.
Yes, Super record is back with Ceramic bushing in the RD and Ceramic bearings among other spots.
Everything is new except the brakes and minor aesthetic changes to the cranks.
Centuar and below will get a complete overhaul, but remain 10 speed.
Bora and Hyperon will both see ceramic bearings.
2 New Tubeless wheelsets: Neutron Ultra and Shamal Ultra?
Wow, with 09 DA 10 Mech and DA 10 Electronic coming, Campy just raised the bar again.
Or did they?
Personally, I don't see the need for 11 speed gearings, unless you want straight block cassettes. Will this sell well or at alarming rates? Who know. But with 20-25% increases I have heard about from Campy, it will cost a pretty penny. What's Super Record going to cost?
Personally, I am staying with Camp 10 for a while.
Wednesday, May 7, 2008
Friday, April 18, 2008
The crankset gets an important upgrade: The axle is bigger, it is now 30mm of diameter instead of 24mm. The new BB 30 Standard. * Stiffer * The weight is reduced * Q-Factor is reduced * Bearings are larger, meaning stiffer and more durable as well.
There are two new cassettes offered beside the current 11/23 and 11/26: - 11/25: 11, 12, 13, 14, 15, 17, 19, 21, 23, 25 - 11/28: 11, 12, 13, 14, 15, 17, 19, 22, 25, 28
SRAM RED TT
SRAM offers some new time trial components.
- A PowerGlide technology chainring: * 55, 54 and 42 teeth * Grey tungstene finish to improve resistance * Aero chainring which increase the stiffness too - The 500TT shift levers have a new a red touch * cheaper than the carbon version * the rear shift lever is indexed, the front one is operated on a friction mode * 154g per set - Aero brake levers, the 500TT: * red color * 115g per set, which is 16g heavier than the carbon version
Certainly the most reworked for 2009. It uses a lot of the systems featured on the high range groupsets. This is probably a best-seller if the price isn't too high. - Black finish - Carbon levers (320g, 20g saved) * System Zero-Loss for the front derailleur (read further explanations above) * The brake and shifter cable housings can run along either side of the handlebar * Reach adjustment * Wider aluminum shifter paddle - Aluminum hollow cranks, OCT technology (open core) * 40g are shaved off the previous version * Available in compact (110mm), and standard (130mm) * Cranks length from 165 -180mm
The SRAM Force groupset get several upgrades from the high range Red groupset.
Only the levers are modified:
* They are longer
* The shifter paddle is reworked, it is widened
* The brake and shifter cable housings can run along either side of the handlebar
* Reach adjustment
* The front derailleur with Zero-Loss technology which engages front shift immediately.
Thursday, April 10, 2008
Shimano is really doing a great job with the new 2009 line. They will surely get some folks who left them for SRAM to come running back!! Even us Campagnolo guys are eyeing the new DA!!
Tuesday, March 18, 2008
Friday, March 14, 2008
2009 Shimano Dura Ace 7900. New & improved gossip.
Most of the press we've seen in the last few months about the new-for-2009 Shimano Dura Ace has focused on the electronic version of DA. Stefan Schumacher medaled on eDA at last year's World Championship Road Race, and he and his Gerolsteiner team mates have served as guinea pigs for eDA ever since. While the pure novelty of electronic shifting tantalizes, we got our own medals (for bravery) for fighting at the Battle of Zap and Battle of Mektronic. While we're intrigued by the alleged telepathic shift quality of eDA, it's hard to shed our concerns for its weight, its durability, and its reliability.
The excitement over eDA has been noisy, and it's obscured an underappreciated fact: Along with eDA, Shimano is also releasing a new version of non-electronic DA. It'll be known as Dura Ace 7900, and we've finally seen our first confirmed technical details about 7900. The purpose of this What's New posting is to shed some light on what you'll be seeing in the new-for-2009 non-electronic Dura Ace.
Here's what we DON'T know about Dura Ace 7900: Weight and cost. As soon as we get this info, we'll pass it along. But, for now, all we have is basic technical info. And, sorry, we don't have photos either.
Here's what we DO know, on a component-by-component basis:
STI Levers -
- Say farewell to exposed shifter housing. Shimano is making the change to under-the-bar-tape cable routing They refer to it as "integral shift cables". We wonder if Shimano-sponsored pros will find digging deep on the front a but tougher without shift cables to grab on for stability…
- "Better access to the lever from upper side with closer pivot." Our interpretation of this means that the shape of the brake hood will be different. We've never enjoyed the deep hook of DA brake hoods, and to our ears it sounds like Shimano is modifying the shape to make it more SRAM/Campy-like. In other words, no more plunging hook, and instead you'll see a flatter hood. Beyond the ergonomic improvement, Shimano also claims this leads to smoother braking.
- You get a reach adjustment mechanism. This is a nice feature of SRAM Red, as well. Folks with small hands should be very pleased.
- 20% shorter stroke to achieve shift engagement on the right lever.
- Weight savings thanks to the use of a carbon brake lever and a titanium fixing band & bolt.
Photo © Tim de Waele
Rear Derailleur -
- Carbon! The pulley plate will be made from carbon fiber. Shimano is a company built on their commitment to the forging of alloys, so any sort of branching out into composites is a big, big deal.
- Increased chain wrap capacity. In other words, you can use a wide range of gears (e.g. a 50/34 & an 11/28) without having to resort to a "Triple" rear derailleur.
- You get an "enhanced pulling cable method" with an audible click when the shift is complete. But the price of superior shifting is this: Dura Ace 7900 STI Levers and the 7900 Rear Derailleur will not be compatible with current 7800-series Dura Ace.
Front Derailleur -
- Shimano claims that your days of trimming the front derailleur are over. No trimming will be required. This is a pretty big coup when you compare it to SRAM, since one big upside of Red (in comparison to their Force and Rival gruppos) was its inclusion of FD trim.
- The FD spring tension has been re-tooled to achieve "featherlight downshifting".
- Put aside your sugar-plum visions of a DA Carbon crankset. Rather, Shimano has forged their 7900-series aluminum crank with even thinner walls to make it lighter than any production carbon crankset in the marketplace.
- When you use the 7900-series crankset with the new 7900-series chain, you'll get no front derailleur rub thanks to its new chainring/spider design. This also allegedly provides improved power transfer, thanks to the superior mating of chain and chainring.
- More weight savings comes from its new aluminum/carbon composite BB axle.
- Shimano will also introduce a 7950 version of the crankset, with 50/34 chainrings. This will be the first-ever Dura Ace compact crank (a full, what, 7 years since FSA introduced theirs?)
- The 7900 chain is known as the "Super Narrow" chain. The redesigned outer plate resists chain suck, and the new design of both the inner & outer plate mesh with the chainrings with such precision that Shimano claims it reduces mechanical friction by 0.6%. We're a bit unsure how to parse what that 0.6% converts to…Does that mean an extra 2.4w when you're making a 400w effort? We're unsure, and we're eager for a fuller explanation. Perhaps more important is the fact that Shimano also says it's a quieter chain.
- The 7900-series chain has hollow pins and perforated plates to further reduce weight.
- Shimano will introduce a "Quick Link" for its 10-speed chains. Our impression is that this means tool-free installation.
- Like the chain and the crankset, the cassette sprockets get fine-tuned to optimize shifting, and the cog carrier is a lighter-than-ever aluminum.
- You'll see a wider array of cassette ratio options. In addition to all of the options you get in 7800, you'll also see an 11/25, 11/27, and an 11/28. Before you laugh at the 11/28, keep in mind that this is SRAM's #1 selling cassette ratio! All the ratios made in the 7800 will be produced as 7900-series models as well.
Brake Calipers -
- Dig this: "Enhanced brake arch proportion." We think this means that you get quicker caliper response when you hit your brake lever, and perhaps better stiffness under heavy braking. We suspect that this is a photo of the new brake. Interestingly, the boys over at the Weight Weenies forum pointed out that this poor rider appears to have his brake shoes on the wrong side…
- Lower profile outer cable stop. This improves cable routing, which decreases drag and improves the snappiness of the lever. If you've ever installed a set of Zero Gravity brakes, you know that fine-tuned brake cable routing is something you should never take for granted.
- The brake pad compound changes. Shimano claims that the improvement will be most noticeable in the wet, where stopping power improves 210%. In the dry, you should expect a 120% improvement in stopping power.
- Add'l titanium hardware saves overall weight.
Flight Deck Computer -
- It's still integrated into the STI levers, but the functionality gets much broader -- It includes a heart rate monitor, altimeter, and an inclinometer. It's a full-on 2.4GHz wireless system, and you can even download data wirelessly onto your PC.
A final note on our understanding about backwards compatibility:
Rear Drivetain -- The 7900 system is only compatible with other 7900 components. The 7900 rear derailleur is compatible with 7800-series cassettes, but that's it. There is no other cross-compatibility. This also means that 7800-series components cannot be used in piecemeal with 7900 if your plan is to upgrade one component at a time. More or less, you'll need to upgrade to 7900 STI, rear derailleur, cassette, and chain in one fell swoop.
Front Drivetrain -- Same story. There's an Iron Curtain between 7900 and 7800. The only kinda, sorta compatibility is between the 7900 front derailleur and the 7800 crankset. Shimano states "slower shifting may occur depending on frame dimension" if you choose to mix things like this. We're not sure if "dimension" means frame size or geometry or what. But we can't imagine someone running a full 7800 bike with the exception of a 7900 front derailleur, so it's not something we're terribly worried about.
Brake Systems -- The 7900 STI Levers are compatible with 7800-series brake calipers.We're looking at a best-case scenario of a late September 2008 delivery timeline.
Tuesday, March 11, 2008
I hope to get the latest and greatest news to you, along with some random thoughts weekly!
If you have Light-Weight Bicycle News, Weight Weenie Articles or pictures, send them to us!
We can use some reporters!
email: DIRT BOY