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Single chainring road racing setup
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Nick Payne
Joined: 10 Jan 2004
Posts: 2377
Location: Canberra, Australia

2/2/18 7:14 PM

Single chainring road racing setup

Been watching the Cadel Evans road race and a couple of stages of the Suntour over the past few days, and I've noticed that the Aqua Blue team is using a single chainring setup on their team bikes. One of their riders actually won yesterday's Suntour stage, and another of their riders won the KOM jersey in the Cadel Evans race (though I noticed that even with a wide range cassette he was using a pretty slow cadence up the KOM climb each lap). However, none of the courses so far have had real mountains in them - rolling hills yes, but not long grinding climbs, and I remain skeptical that a 1x system for road racing will work in the mountains. A wide enough range cassette to give the same gear range as a 2x system will have big jumps between gears, and the alternative would be to compromise either the big gear for driving on descents or the small gear for climbing at a decent cadence.

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Brian Nystrom
Joined: 26 Jan 2004
Posts: 4163
Location: Nashua, NH

2/3/18 7:06 AM

IIRC, they're sponsored by 3T

They're using their new Strada road bikes that can only handle 1x drivetrains. It seems like a very limiting proposition and I doubt that they'll still be riding them in Grand Tours.

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henoch
Joined: 12 Jan 2004
Posts: 1578

2/3/18 8:55 AM

Yeah I think that we are all waiting to see what they do once they hit the big mountains, they are saying that they will stick with the 1x.
Also remains to be seen what races with big mountains they actually get to race.
They didn't get an invite to either Giro or Tour, but they won stages last year at both Suisee and the Vualta so they are deserving some invites to some of the bigger races.

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Jesus Saves
Joined: 16 Jun 2005
Posts: 1131
Location: South of Heaven

2/3/18 10:01 AM

I hope their bikes still have the front derailleur or David Millar's 2003 bike is not being recycled.

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Sparky
Joined: 08 Dec 2003
Posts: 16693
Location: Portland, OR

2/3/18 10:07 AM

"Millar's 2003 bike is not being recycled."

I think that train left the station a while ago. ;)

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dddd
Joined: 11 Jan 2004
Posts: 3221
Location: NorCal

2/3/18 2:05 PM

For the first time in years I have been anticipating the early races on the pro calendar, to finally see what this single-ring concept can yield in the hands of a creditable team.
As one who rides vintage bikes as close to stock as practical, I've been convincing myself for years that the lack of super-tightly spaced gears may not be much of a hindrance at all, once a suitable strategic algorithm is in place in the rider's book of tricks.

My understanding is that this team will be using cassettes (11s for now) which employ an age-old gearing progression that sneaks bigger gaps into the middle portion of the cassette.
My own most-used cassette (freewheel actually) of late, for here in the hilly foothills, is 13-15-17-20-24-28t, and appropriately used with friction levers.
Changing the biggest cogs for 23 and 26t makes the ratios sporting-perfect for this rider and still gives a low enough low for all but the longest/toughest rides.
I reckon the team will be swapping cassettes for each event to minimize any limitations imposed by 1x.
Note that 1x systems have zero unusable sprocket combinations.

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Steve B.
Joined: 19 Jan 2004
Posts: 699
Location: Long Island, NY

2/3/18 3:11 PM

The whole 1X concept for road bikes just puzzles me. It's not like front shifting suddenly started to suck, if anything and with Di2, it's even better than I recall with my 5800 series.

As well, Shimano allows automatic shifting with Synchro, so if anything is stating that they are not jumping on the 1X bandwagon anytime soon.


Last edited by Steve B. on 2/3/18 4:14 PM; edited 1 time in total

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Sparky
Joined: 08 Dec 2003
Posts: 16693
Location: Portland, OR

2/3/18 3:33 PM

I am trying it on my old Litespeed as of about 3 weeks ago.

10 speed, 38t single narrow/wide chainring, with an 11-34 cassette. Planned use was for hilly & city riding.

I am planning on using for road riding this season a 14-28 Juniors 11s cassette with both an 34/50 and a 28/42. The latter not setup up yet, but I cobbled a 28/42 SRAM Force setup with low Q and road double chainline. Just need to decide which frame to use it on being a braze on tab won't be low enough..

I don't see the 1x11 thing really working for normal non CRIT stage racing in my minds STI.

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Nick Payne
Joined: 10 Jan 2004
Posts: 2377
Location: Canberra, Australia

2/3/18 4:15 PM


quote:
Just need to decide which frame to use it on being a braze on tab won't be low enough

Actually, Sugino make a nice adapter to allow a derailleur on a braze-on tab to be lowered at least half an inch more than if the derailleur is attached directly to the tab. Photo of one that I fitted to one of my wife's bikes - the big chainring is 39t.

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Brian Nystrom
Joined: 26 Jan 2004
Posts: 4163
Location: Nashua, NH

2/4/18 8:52 AM

Nice, simple solution

The front derailleur looks rather high. Is that necessary for the cage to clear the chainstay?

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daddy-o
Joined: 12 Apr 2004
Posts: 3201
Location: Springfield

2/4/18 9:53 AM

FD looks pretty much bottomed out on the adapter.

Nick, with a set of after market chainring bolts you could actually bring this Franken-drivetrain to life. Let me guess, Shimano rear derraileur and a Campy cassette? But who am I to argue with success.

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Nick Payne
Joined: 10 Jan 2004
Posts: 2377
Location: Canberra, Australia

2/4/18 12:37 PM

@Brian - no, the pivot for the cage angles outwards when on the "big" chainring, and the cage dips down as it moves inwards. It only clears the top of the chainring teeth by a couple of millimetres.

@daddy-o - no, the rest of the drivetrain is all Shimano.

On metal frames where the seat tube is round all the way to the bottom bracket, with small chainrings it's often possible to fit a band-on FD below the braze-on tab, so you're not limited in your chainring sizes by the tab position. I did that on one of my wife's older bikes, where she was using a 42t large chainring on a DeRosa SLX frame.

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dddd
Joined: 11 Jan 2004
Posts: 3221
Location: NorCal

2/5/18 11:47 AM

Steve B. wrote:
"The whole 1X concept for road bikes just puzzles me. It's not like front shifting suddenly started to suck, if anything and with Di2, it's even better than I recall with my 5800 series.

As well, Shimano allows automatic shifting with Synchro, so if anything is stating that they are not jumping on the 1X bandwagon anytime soon."


It comes down to four or five advantages, which now, may "make their value known" in quantitative, net terms.

There is the loss of weight of the left shifter mechanism, cable, housing, adjuster, front derailer, it's mounting, and small chainring.

The crankset can be redesigned around a single ring for better aerodynamics. And the loss of front derailer and it's mounting, cabling, cable stop and cable adjuster reduce aerodynamic drag a bit more.
The frame designer is allowed a freer hand in terms of tube shaping for lowest weight while allowing for sturdier driveside chainstay and seattube optimized for aerodynamics with still-sufficient tire clearance.

The rider no longer ever needs to think about when to dump the chain down to the small ring as a climb becomes steeper, a time when other riders will always lose some momentum and speed. And the same applies during upshifting to the big ring.

There should be a decrease in dropped chain incidents, and the possible catastrophic failure of any and all front shifter, cabling and derailer componentry becomes a thing of the past.

Now at the UCI pro level the weight issue would seem to be insignificant, though again allows greater design freedom with respect to the weight of the frame, which can thus be allowed to be heavier. The weight advantage could also allow for the addition of electronic shifting and who knows what other engineering upgrades that can be packed onboard, such as beefier brakes or even suspension devices.

The single ring concept invites the use of a larger largest rear cog, which gains clearance for an increase in cassette cog count which may be exploited before the rest of the peloton gets to use a more comprehensively redesigned 12s drivetrain.

These technical advantages are of course in addition to the assistance that this team may receive from beneficiaries of the marketing value of 1x Road, since pro-racing success of this 1x concept could only help with the marketing of "gravel" or other 1x road bikes, especially to current off-road riders who are typically attracted to the familiar technology that is on their current mtb's and who thus might cross over to the roadie realm with an additional bike purchase! The same would apply to disc brakes of course, which the industry as a whole seems to embrace for it's marketing value.

So adding it all up, does this team do better this year, that is the net final question.


Last edited by dddd on 2/5/18 3:21 PM; edited 1 time in total

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Nick Payne
Joined: 10 Jan 2004
Posts: 2377
Location: Canberra, Australia

2/5/18 3:19 PM

In the Cadel Evans race, the Aqua Blue rider in the break was, according to the commentators, using a 46t chainring with a 10-42 cassette. Even so, I could see that each lap up the couple of steep climbs on the course he was in a lower cadence than the other breakaway riders who were using two chainrings. If a rider putting out 400-500W on a bike at the UCI weight limit can't maintain a decent cadence, your average rider just out to enjoy themselves will need a chainring down around 30t, and I can't see that being viable on the road.

We just returned from a week of riding in the mountains down in Victoria, and there were quite a number of climbs where I used my 29x40 bottom gear - I had 42x29 chainrings and an 11-40 cassette.

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Sparky
Joined: 08 Dec 2003
Posts: 16693
Location: Portland, OR

2/5/18 4:14 PM

My last Crater Lake ride I had 22 granny w/11-30 cassette, 3800' elevation IIRC. I would have used lower if I had it, but the bike loaded was @ 46 lb + my bulk. I had both 11-32 and 11-34 I could have put on. I lent the 11-34 to my friend who has my old TCX with 26/39/52 and a chain drop device on the seat tube. I coulda/shoulda maybe put on the 11-32... But I never blew up or anything, although the longest steepest 5.3 miler I stopped 1/2 up at a view point. At least that is why I say I stopped, for the view. ;)

I still got ahead of Scott on the climbs [his bike 25lb lighter than my loaded truck], cadence advantage I think, so low gears.. yeah. We both ran 32 tires which on the descents were the bomb, literally. But a bit of a drag going up perhaps. Looking forward to next time [09/2018?] with a 15-16lb bike and stupid light wheel/tire combo. With a 34/34 low...

My last GH800-11s cassette purchase turned out to be a good one for a climbing bike. And the 34 with the GS Rear DR works with the minutest of B-screw diddle...

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dddd
Joined: 11 Jan 2004
Posts: 3221
Location: NorCal

2/5/18 5:42 PM

For guys our age, the option will be to use something like an Eagle cassette!

This being a cutting-edge race bike, old guys living in the hills might not be the primary target customer.
I'm seeing more and more roadies using single-ring "gravel" bikes with what appears to be a standard mtb cassette, so no limit on gearing and they seem to be keeping up, albeit not in a race.
Riders everywhere also often have at least one reason or another to fear the reliability and service needs of their front derailer, the mtb'ers are done with them.

I think it will take a team's success with 1x to make it as popular on the road as all the high-end, Sky-aping Pinarellos around here, and I don't think that one of these 1x bikes will much slow any of us sporting recreational roadies any more than the weight of their existing Di2 battery is perhaps slowing those same riders down today.
This is the industry's chosen launch time to see the overall merit of the 1x-Road concept in this time of ever-increasing cog count.
And as with any other yet-proven technology in a competitive market, someone has to be the first to risk coming out with their version perhaps too soon (think Mavic Mechtronic/Zap, Matthauser Hydro or Teledyne Titan).

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Anthony Smith
Joined: 12 Jan 2004
Posts: 840
Location: Ohio

2/8/18 1:54 PM

Gearing

Guys our age--huh? I guess that would include me.

So on my road bike, I use 39,42,or 44 on the inside. I actually prefer the 44, but if I need a lower range, 3 teeth on the front equals about 1 tooth on the back. Big ring 53 or 54. I prefer the 54 as I have lost a bit of cadence since my glory days and a 54x15 will cut it where a 53x15 won't when I still decide to do a P/1/2 race. I'm typically on a 15 when others are on a 13 so I still ride relatively high rpm on the road as well as on the track.

On the road I use an 11-23 11 speed. I have no problem climbing anything I encounter.

Note: Edit was to fix "autocorrected" words


Last edited by Anthony Smith on 2/11/18 2:01 PM; edited 1 time in total

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Brian Nystrom
Joined: 26 Jan 2004
Posts: 4163
Location: Nashua, NH

2/8/18 5:02 PM

I did the same thing...

...40 years ago. ;-)

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Steve B.
Joined: 19 Jan 2004
Posts: 699
Location: Long Island, NY

2/8/18 6:50 PM

Note that Shimano has seemingly discontinued the 11 spd. 11-23 cassette.

No idea why

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Sparky
Joined: 08 Dec 2003
Posts: 16693
Location: Portland, OR

2/8/18 8:01 PM

Below capacity of drivelines offered currently?

Back in our 12-23 with 42/53 daze we'd have scoffed at this compact sheit.

I remember well going to the 39 with a 25 and getting razzed big time for it. Now a 12-27 with 34/50 is as high as I go.

But I had my broken leg and 3 years of pain trying to bike for an excuse to go compact cranks, with a cassette middle cog removed and a 30 top added.

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Steve B.
Joined: 19 Jan 2004
Posts: 699
Location: Long Island, NY

2/8/18 8:38 PM

I think the most common road setup on production bikes is the Shimano 34/50 crank with an 11-28 cassette.

I personally like tighter gearing with some bail out gears at the low end, but I live on Long Island where corn cob is useful in wind.

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Sparky
Joined: 08 Dec 2003
Posts: 16693
Location: Portland, OR

2/8/18 9:04 PM

I use close ratios when riding with fast folks. I will use the 14-28 juniors cassette when I get to getting with the faster farts in a few months. I don;t ride with them this time of the year @9:30 when I can ride in the afternoons with much higher temp. Not a die hard like that anymore.

14-15-16-17-18-19-20-21-23-25-28 with a 34/52 setup up front. Flatter rides are all 52 pretty much. The 52 is outside capacity, but the Di2 FD takes no prisoners. And I figured with the 14 the 52 would equalize a little, or at least be a little better on top.

___
My first Di2 group I put together with some used parts. Pulls with little use. I bought the chain 11-32 cassette, chain rings [34/50], front DR, GS RD and a wire or two for 100.00, I had got the ST-6779 [also works with 11s] new for 99.00.

The seller put an XTR rear DR with 11-42 I think, and a single chain ring on. I saw him again after
a season and he said he loved it still. Now XT has a Di2, so the conversion costs a lot less.

IIRC, the Di2 logic for MTN is in the RD while the Road Di2 logic is in the FD FWIW.

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Anthony Smith
Joined: 12 Jan 2004
Posts: 840
Location: Ohio

2/11/18 1:59 PM

bummer

and they never made an 11-21 straight block

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Sparky
Joined: 08 Dec 2003
Posts: 16693
Location: Portland, OR

2/11/18 2:16 PM

The 12-25 11s has nice spacing IMO.

CS-6800-## [on sale Nashbar 49.00]

11-23: 11-12-13-14-15-16-17-18-19-21-23
11-25: 11-12-13-14-15-16-17-19-21-23-25

WEIGHT: 11-23t: 212g, 11-25t: 232g

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Anthony Smith
Joined: 12 Jan 2004
Posts: 840
Location: Ohio

2/12/18 7:37 AM

The other problem

The other issue with single ring setups is the chain falling off the chainring.

On single ring TT bikes in the 1970s some people fashioned a "chain guide" to replace the front derailleur to deal with this problem.

My cross bike has a 1x10 setup and I had to mount a chaingaurd on both the inside and outside of the chainring to keep the chain from falling off when running in either the high or the low gear in the back. (My chainline is spot on, I measured it).

So...why is this problem not happening on the 1x11 or 12 road bikes. Even with a flexible chain, the angle of chain run is pretty severe.

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