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these pancake 1x cogsets boggle the mind!!!
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Sparky
Joined: 08 Dec 2003
Posts: 16467
Location: Portland, OR

5/27/18 11:18 AM

Just went a googling for SRAM Eagle Rear Derailleur capacity spec. SRAM apparently does not publish it. ;{, that I could find...

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dan emery
Joined: 11 Jan 2004
Posts: 5963
Location: Maine

5/27/18 11:25 AM

Fair enough

I was thinking in the context of road/gravel riding, of course hard core MTB is a different story.

However when I said "I" don't expect to ride over 27%, that was entirely accurate :)

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April
Joined: 13 Dec 2003
Posts: 6329
Location: Westchester/NYC

5/27/18 11:43 AM

Dan


quote:
when I said "I" don't expect to ride over 27%, that was entirely accurate :)

But, but, but...

if the gears are there, you may just go up those 27% climbs without too much a thought!

[EDIT]
What's a mountain bike that's not a road/gravel bike? Fat heavy tires and too low gears for on-pavement motoring.

But with the ever larger gear range, (the lack of which I lamented 15 years ago when 10 speed first came out), the distinction between a 29'er mtn bike with a 1 1/2" semi-slick tires vs a gravel bike with a 40mm tire is getting quite blurry.

e.g.:
The last D2R2 we both rode (the one with the bridge out and the associated route changes), I took one of the option that involved a section of single track that's every bit a "proper" mountain bike trails! I did it on my gravel bike as usual. I walked one or two obstacles, but some in the group I rode with rode the whole thing without dismount at all.

Having done extensive mountain biking, I don't see "gravel" as a distinct bike type. ("cross" bike, however, had a distinct origin, from cross racing) It's just the middle of the continuum from road to mountain. So as the equipment continue to improve, the range of what gravel bike could handle (for that matter, what mountain bike can handle on the road side), continues to expand too. It's beyond just the lines getting more blur, they actually starts to overlaps a great deal!

Last edited by April on 5/27/18 12:48 PM; edited 6 times in total

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Sparky
Joined: 08 Dec 2003
Posts: 16467
Location: Portland, OR

5/27/18 11:58 AM

" "I" don't expect to ride over 27%"

Maybe for 100 yards, then I expect to walk. ;)

" I really don't see "cross/gravel" as a distinct bike type."

You are just too smart and have enough self control to not drink the cool aide. ;)

Until you don't, should that occur.

I'd suggest the low low BB for the 'gravel' bikes make them extra stable feeling in cases of loose surface. Subtle difference, but it is there.

I have always liked Low BB heights, perhaps long femurs have a lot to do with it. Having 1-1/2" more inseam than average for my height, lower CG on the bike is realized and appreciated.

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April
Joined: 13 Dec 2003
Posts: 6329
Location: Westchester/NYC

5/27/18 1:08 PM

I don't think it's the Coolaide factor for most riders. They buy what they need (or perceive to need, based on their buddies' recommendation). Those who buys multiple bikes just because there's a "new kind" of bikes becoming fashionable are the minorities. Most road vs gravel bike purchases were made by riders who outgrown whatever bike they have and (more or less) "in need" of a new bike to do certain type of riding they've gotten interested in.

If they were newly minted roadies aka club riders, they would typically choose "club/century" road bikes, with or without disc brakes. Many of which are fat tire capable anyway. So they end up with a "non-gravel" bike that can easily be converted to gravel use anyway.

If they've already got a road bike and are "upgrading". It's either for a lighter one with better groupo, or the same including the gravel capability (disc brake goes a long way in that direction).

I do get the different handling characteristic of the various bike types. But just as road racing bike isn't the best suited for riding a century, yet it's been ridden for decades by club riders. A "gravel" bike can be used for touring, for dirt roads, or for single track, despite the limitation due to such minor geometry mismatch.

When one isn't racing, the focus changes a lot. The frame geometry is more about comfort & efficiency. So is gearing too. Range trumps gaps, reliability over shifting speed. So on and so forth...

Yes, I'm a bit too smart for the marketing machine. But it's got more to do with I'm not trying to keep up with the next faster group (aka, subconscious racing or ego-racing). That saves me from all kind of pressure to fantasize after the latest and greatest, nor falling victim to the newest unobtainium.

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Brian Nystrom
Joined: 26 Jan 2004
Posts: 4057
Location: Nashua, NH

5/27/18 1:12 PM

"I really don't see "cross/gravel" as a distinct bike type."

That depends one what you're comparing them to. They are very distinct from MTBs, but quite similar to road bikes.

Dan, I'm running the same gearing as you and find that it works great for gravel/dirt roads and quite well for most of the singletrack I ride, too. My MTBs are geared lower, but I'm not sure how much of an advantage the ultra-low gearing really is. You eventually get to the point where it's faster to walk.

One interesting thing I noticed in the descriptions of the new XTR is that they make reference to the "ground clearance" of the derailleur cages. Whoa...

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dan emery
Joined: 11 Jan 2004
Posts: 5963
Location: Maine

5/27/18 1:41 PM

Gravel cross etc.

When I rode the D2R2 180, I just didn't feel like I wanted a lower gear than the 30x32 I had. I expected to walk at least one of the hills, but on all of them I found a rideable rhythm. I'm not a stranger to low gears, having ridden Mt. Washington 12x in gears ranging from a 26x26 to 20x29.

For gravel rides I just use my trusty Gunnar Crosshairs (traditional steel cross bike).

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April
Joined: 13 Dec 2003
Posts: 6329
Location: Westchester/NYC

5/27/18 2:14 PM

I guess the point I'm trying to make is, there's less need for specialized bikes with the availability of the pie plates.

Say, on your D2R2 bike, what's the harm of having one or two more extra low gear that you only use once in a blue moon? There is if the trade off is bigger gap or less high gear. But with the new pie-plates (and the 12+ cluster), that extra low can be had without any sacrifices on the high end or the gaps.

In case you forgot, one of the introduction of the D2R2 organizer wrote (paraphrase) "We didn't picked the steepest dirt roads in the area. We just pick the most scenic ones. There're plenty of steeper ones than what's included in our route".

Back to the original post.

It really is the inevitable end result of the ever increasing # of speeds in the rear cluster. You either keep shrinking the gap between gears, or widen the range of the total setup. In a way, the "lack of need" for low gear you profess is partially the motive to go to 1x: If the rear cluster alone is capable of what's needed in the traditional 2x setup, it's only logical to drop the 2nd chainring! (or for those who enjoy being mountain goats, 2x turns a single purpose bike into a multi-purpose bike, capable of climbing single track and paceline in a Grand Fondo)

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dan emery
Joined: 11 Jan 2004
Posts: 5963
Location: Maine

5/27/18 2:33 PM

Harm?

Well for one thing I'd need new derailleurs, for a capability I don't need. If I were getting a new gravel type bike I don't know what I'd do, but I'm not. I'm an "if it ain't broke don't fix it" kind of guy. And I'm really not looking for roads steeper than Achambo. And elimination of the front derailleur does nothing for me. On my road bike I'm happy with a 34x28 low. But if you want a pie plate by all means go for it.

And BTW, one year I was standing around in the starting queue and Sandy Whittlesley (founder and guru of D2R2) complimented me on the Crosshairs and the setup. :)

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April
Joined: 13 Dec 2003
Posts: 6329
Location: Westchester/NYC

5/27/18 2:49 PM

I'm not buying a new bike either.

But when the time comes that I get a new bike, I'm definitely going for a pie-plate! Heck, I already have one by the standard of its time: 30x32 low. But by today's standard, that's pretty "normal"!

I almost always get the widest gear range I can reasonably buy off the shelf. I tend to take my bikes to where they're NOT designed to go, just because I'm there, and "it" was there between me and my destination. Whether "it" was a segment of single track or a wall. So having extra gear in reserve has saved me from many of go-arounds or other unpleasantness. As such, I'll continue to favor that same methodology (of spec'ing extra gear that I may questionably not need).

Also, as I tend to keep my bikes for decades rather than just years. My age will catch up to the gears I bought long ago.

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PLee
Joined: 08 Dec 2003
Posts: 3583
Location: Brooklyn, NY

5/27/18 7:13 PM

By the way, my 6 speed Brompton gets that way using a 3 speed internal rear hub and a two cog rear derailleur. So, yeah, you can couple a rear derailleur with an internal hub.

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dan emery
Joined: 11 Jan 2004
Posts: 5963
Location: Maine

5/27/18 8:29 PM

6 speed

I didn't question that. I questioned how a rd was going to work with a 14 speed Rohloff, and I'm still waiting.

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Sparky
Joined: 08 Dec 2003
Posts: 16467
Location: Portland, OR

5/27/18 8:31 PM

SRAM DD3 Dual Drive

Weight: 985 grams (hub) 320 (derailleur), 162 grams (shifter)


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April
Joined: 13 Dec 2003
Posts: 6329
Location: Westchester/NYC

5/27/18 8:41 PM

Iím a bit confused.

I thought the advantage of internal hub is itís protected from the elements. But mating it with a regular external gear seems to defeat the purpose...?

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Sparky
Joined: 08 Dec 2003
Posts: 16467
Location: Portland, OR

5/27/18 9:04 PM

I think is it targeted towards a recumbent bike design where the long chain and a triple ring crank is a problem or something.

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April
Joined: 13 Dec 2003
Posts: 6329
Location: Westchester/NYC

5/27/18 9:26 PM

???

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Sparky
Joined: 08 Dec 2003
Posts: 16467
Location: Portland, OR

5/27/18 10:45 PM

I was offered a wheel from a parts bike with that hub that came from a recumbent bike. I thought about toying with it, but did an Automatix 2 speed instead.

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Jesus Saves
Joined: 16 Jun 2005
Posts: 1106
Location: South of Heaven

5/28/18 7:30 AM

What makes a rolhoff hub special that it cannot be integrated with a rear derailleur design? That is if one was designed to accept a cassette instead of a single sprocket.

Sich setup works well with folding bikes to solve the problem with the inability to easily equip them with a front derailleur

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dan emery
Joined: 11 Jan 2004
Posts: 5963
Location: Maine

5/28/18 10:19 AM

Rohloff

Well to my eye the internals (14 gears not 3) look pretty bulky and I don't see where you get room for a cassette, even if for some unknown reason you wanted one. But I'm no engineer.

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Sparky
Joined: 08 Dec 2003
Posts: 16467
Location: Portland, OR

5/28/18 11:03 AM

Doesn't the 14s Rohloff already have the range of a 11-27 triple setup.

A friend has one on a Ti bike with Ti fork he never uses. He had it all on a Surly Trucker and boy it was a heavy bike. So he had it all moved to a new Ti Frameset with new brakes and it lost a bunch of weight. [And a lot of coin] So the dent in the floor where it sits unused are not as deep as with the Trucker. ;) He is not as blessed as a lot of us aging cyclist to stay on the bike the way he hoped he could.

The return cable thing and weight both notable items in the design I recon.

The innards are a little scary looking. ;)

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dddd
Joined: 11 Jan 2004
Posts: 3203
Location: NorCal

5/28/18 11:42 AM

"...The innards are a little scary looking. ;)"

I think that I might prefer rebuilding a unit engine/transmission from a multi-cylinder motorcycle, a familiar one at least.

I was getting a loud squeak while in 1st and 3rd gears on my recumbent's mere 3x7 rear hub, and was sorta dreading taking the thing apart without full doc's at hand. I got the crazy idea to pull out the chain from the hollow axle and shoot m/c foaming chain lube into the hole, which immediately solved that problem, whew. :-)>

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Sparky
Joined: 08 Dec 2003
Posts: 16467
Location: Portland, OR

5/28/18 1:49 PM

Ordered a Sunrace 11-36 and a RD-8050 GS rear derailleur. Time to get the Di2 Groupo outta the box ans see if I can't get a 28/42 crank to work with the FD-6870.

So the Strong Disc will get the little port hole Carl put on used... Although I hate to give up the 22/32/44 honestly..

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Jesus Saves
Joined: 16 Jun 2005
Posts: 1106
Location: South of Heaven

5/28/18 2:45 PM

Obvious answer: wider dropouts to accomodate the freehub body for the Rolhoff hub, much like done for fat tire bikes.

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Sparky
Joined: 08 Dec 2003
Posts: 16467
Location: Portland, OR

5/28/18 3:11 PM

Or just install on your 1200mm wide fat bike drop out spaced frame... ;)

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dan emery
Joined: 11 Jan 2004
Posts: 5963
Location: Maine

5/28/18 3:16 PM

Obvious question

Why would anybody bother to do that?

You need to make a special frame that can only be used with that hub, in order to get a gearing capability nobody needs, while adding significant weight and expense to an already heavy and expensive component, and eliminating the low maintenance, simplicity and weatherproof characteristics that are a large part of the Rohloff's appeal.

As a longtime Rohloff user, you couldn't pay me enough to take that bike.

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