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Out of the box, gravel bike gears are too high. Here's how to sort them out

Want lower gears on your gravel bike? We do, so we set about combining some parts that aren’t supposed to work together to get a massive gear range. Ssshh, don’t tell Shimano.

Gravel bikes are over-geared.

Typical gravel gearing

Out of the box, your typical gravel bike has a 50/34 chainset and an 11-32 cassette, giving a range of gears that’s fine on roads unless you’re riding somewhere very hilly, but with limitations you very quickly bang up against when you venture off road.

That bottom gear is far too high. When I head out of Cambridgeshire to the gentle slopes of Suffolk I find myself wanting something lower for longer climbs. When he tested Trek’s new Checkpoint David Arthur — who is much, much fitter than me — found he had to get off and walk when riding the Cotswolds. "Compact chainsets have no place on gravel bikes," he said in a road.cc office discussion of the issue.

In gear inches that typical 50/34 & 11-32 set up has a low of 29in and a high of 123in — a 428% difference between smallest and largest.

Not only is 29in too high, but so is 123in. You’re never going to use that top gear off-road and you’re not going to get much use from it on the road either. (I could digress into a rant here about component makers supplying almost nothing but pro-class top gears on bikes that will never see a sprint for the line, but that's a topic for another time.)

Let’s try and cook up a better gear selection.

Sprockets

gravel gearing 4.JPG

The arithmetic of gearing makes a change of sprockets the most effective way to get lower gears, and in the last few years Shimano and others have made available 11-speed cassettes with ranges of 11-36, 11-40, 11-42 and even 11-46, all with the same sprocket spacing as our gravel bike’s 11-32.

But there’s a problem: no Shimano road derailleur is rated to work with a sprocket larger than 34-tooth. How about a mountain bike derailleur? Nope. For some reason known only to Shimano, their 11-speed road and mountain bike shifting systems aren’t compatible. Back in the nine-speed days you could use a Deore XT rear derailleur on a road bike if you wanted to, but that’s not the case for 11-speed. What to do?

Well, Shimano’s assessments of derailleur capacity have always been conservative. When Shimano say something won’t work, that often means it won’t work to the high standards Shimano sets, not that it won’t work at all.

And this is what we find with Shimano’s latest GS line of 11-speed 'Shadow' road bike rear derailleurs. The £59.99 Ultegra R8000 medium cage derailleur (RD-R8000-GS for fans of part numbers) is not supposed to be able to shift to a sprocket bigger than 34-tooth, but YouTube is full of backroom tinkerers demonstrating that it works just fine with an 11-speed 11-40 cassette.

gravel gearing 5.JPG

The 105 GS rear derailleur looks geometrically identical to the Ultegra, but is typically £20-£30 cheaper. Could this be a cheap way of getting really low gears on a gravel bike?

To find out, I bought a 105 RD-7000-GS rear derailleur (£40.67), an SLX CS-M7000 11-40 cassette (£39.85) and an 11-speed Shimano chain (£18.17). I thought about pushing my luck and going for 11-42, but I wussed out. Maybe another time.

The cassette is a big beast of a thing. I don’t think I’ll ever quite get used to just how huge a 40-tooth sprocket is, never mind the 50-tooth and bigger sprockets now available for mountain bikes. Rotor’s recently-announced 13-speed system includes a 52-tooth sprocket. When Ah were a lad, that were a chainring!

The 11-40 cassette fits straight on the hub of my Prime RR-28 wheels in place of the 11-32, and the 105 R7000 GS rear derailleur substitutes perfectly for the 105 5800 GS unit. To give the derailleur the best chance of handling the big sprocket I dial the B-tension ‘angle of dangle’ screw all the way in, pulling the body of the derailleur as far back as it will go. I tweak limit screws and cable tension and run carefully up and down the gears.

Success! It shifts just fine to that huge sprocket, clicking into place as if it were designed to.

I’m still running the original chain, so I try shifting the front mech into the big ring. Bad idea. It’s immediately obvious that things are going to go seriously wrong if I try to use the big/big combination.

I ditch the original chain and fit the new one I’ve bought. At this stage I don’t have the chainset I want to use, but I want to ride this weekend. The existing chain would probably work fine with the 46/30 chainset I’m waiting for.

Out on the road and the trail, the difference is soon obvious. I keep glancing down, thinking I must be getting close to the lowest gear, and finding I’m actually in the middle of the cassette.

This isn’t very surprising. The 34/25 combination on the old set-up, 37 gear inches, was two gears from the lowest. In the new set-up’s 34/24 (38.3 inches) I still have four lower gears.

My proving ride takes riding buddy Al and me down a narrow, wet bridleway into the village of Linton, home of the excellent Linton Kitchen cafe. We’re in the middle of a drought, but the leaky water tower at the top of the hill means there’s always a stream here to flick mud up at you.

Fuelled by coffee and carrot cake, we tackle the bridleway in reverse. My current state of fitness could be accurately described as woeful, but nevertheless, it’s a doddle. The average gradient of the top section is about 10 percent, which by Cambridgeshire standards makes this a Proper Hill™, and climbs on trails never have perfectly even gradients. I pootle up it easily. Al zooms on ahead. Not having a 34/40 low gear he doesn’t have any choice, I tell myself. It’s nothing to do with him being a lot fitter than me. Ahem.

For fans of gear charts, this is where we started:

  11 12 13 14 16 18 20 22 25 28 32
50 122.7 112.5 103.8 96.4 84.4 75.0 67.5 61.4 54.0 48.2 42.2
34 83.5 76.5 70.6 65.6 57.4 51.0 45.9 41.7 36.7 32.8 28.7

 

And this is where we are now:

  11 13 15 17 19 21 24 27 31 35 40
50 122.7 103.8 90.0 79.4 71.1 64.3 56.3 50.0 43.5 38.6 33.8
34 83.5 70.6 61.2 54.0 48.3 43.7 38.3 34.0 29.6 26.2 23.0

 

In short, we’ve stretched the range from 428% to 538% with no downside except for a bit of extra weight. I think the gaps between gears are still reasonable; more on that later.

To go even lower (and wider) we’re going to need a change of chainset.

Chainset

One thing I wanted to avoid in this project was trying to persuade road and mountain bike components to work together. There was a time when you could cross the streams easily, but Shimano’s road and off-road derailleurs now have different geometries, so you can’t use mountain bike mechs with road shifters without some sort of cable pull converter. That’s a level of bodging I wanted to avoid.

gravel gearing 6.JPG

That means the chainset can’t be too small or a road front mech won’t work well with it because the curves of the cage won’t follow the shape of the chainring. I therefore settled on one of FSA’s Adventure chainsets in a 46/30 'sub-compact' configuration. That’s enough of a difference to be worth the hassle, but not so much that the shifting will be balky.

FSA makes several 46/30 cranksets, from the high-zoot K-Force and SL-K Modular units with carbon fibre arms to the inexpensive Tempo CK Adventure cranks that fit old-school square taper bottom brackets. In the middle, at a sensible price and weight, there’s the new Energy Modular BB386 Evo crankset (£200), with hollow forged aluminium arms, so I went for one of those.

gravel gearing 3

Fitting was straighforward, with just one caveat: the position of its mount stopped the front derailleur going quite as low as I’d have liked. The front derailleur cage ended up a couple of millimetres higher than Shimano recommends.

That’s another reason not to use a mountain bike chainset. If you have a braze-on front derailleur it’s unlikely you’d be able to get it low enough for the 38-tooth outer of a typical mountain bike double — and of course you probably want a higher top gear than the 38 ring would provide.

The gear range

With the FSA 46/30 chainset, the resulting gear range is massive. Here’s what it looks like:

  11 13 15 17 19 21 24 27 31 35 40
46 112.9 95.5 82.8 73.1 65.4 59.1 51.8 46.0 40.1 35.5 31.1
30 73.6 62.3 54.0 47.6 42.6 38.6 33.8 30.0 26.1 23.1 20.3

 

That’s a 558% range, much bigger than the 428% we started with and most of the extension is at the bottom of the range where it’s most needed. But we’ve also preserved a decent high gear for those zoomy road descents.

Only mountain bikes have lower gears. While single-chainring gearing has all but taken over on mountain bikes, some double-chainring bikes are still available, with gearing down to a positively wall-climbing 22/42 (around 15 inches, depending on wheel and tyre size).

Those systems sacrifice the high end though. With a 36/11 or 38/11 top gear (around 90 inches) you’re going to be doing quite a bit of coasting on descents.

Riding

Out back, the 105 rear derailleur clicks effortlessly and without fuss from one sprocket to another, even when it gets to the final 35 and 40-toothers that it's not supposed to be able to handle. Up front, the old 5800 front mech flips easily between the 46 and 30 chainrings.

This set-up is noticeably gappier than the one it replaced. There are a couple of 15 percent jumps between gears, and the gap between the two highest, provided by the 11 and 13 sprockets, is a whopping 18 percent. I can live with that, but if you're a finely-tuned pedalling machine who struggles to change cadence more than a few percent, you're going to find it a bit jarring.

The big advantage of a gear set-up like this is that it reduces the need to hit the redline every time you go uphill. Back when I was doing a lot of mountain biking, I was always the guy pootling along at the back while everyone raced up the first couple of hills. And I was the one with plenty in the tank at the end of the ride, sitting on the front towing everyone for the last 10 miles home.

Tweaks and alternatives

If Shimano's 11-40 cassette is just too gappy for you, SRAM makes an 11-36 11-speed cassette (£56.99) that shrinks the biggest gap by dropping a 12 between the 11 and 13. With a sub-compact chainset like the FSA that still yields some usefully low gears. SRAM says the 11-36 is only compatible with single-chainring gear systems, but that's almost certainly a matter of marketing rather than engineering.

If you wanted to go electronic, you could assemble a Di2 version of this transmission without breaking any of Shimano's rules. The XTR and Deore XT electronic rear derailleurs work with Ultegra and Dura-Ace Di2 drop-bar shifters. The Di2 rear derailleurs are rated for a 42-tooth sprocket in a 2 x 11 system, so you could go slightly lower than I have. I'd love to hear from anyone who's tried this.

WolfTooth RoadLink

If you wanted to save money, you could use a £19.95 Wolf Tooth Roadlink to extend the capacity of your existing rear derailleur. According to the manufacturer, the Roadlink will extend any non-Shadow GS rear derailleur to work with an 11-40 cassette.

That'll work if you're still running 10-speed too. SunRace makes a couple of 11-40 10-speed cassettes, the £30.59 MS3 and lighter MX3 (£45).

Conclusion

I think the system I’ve put together provides the best wide-range gravel bike gearing currently available, at a sensible price. It's very handy that it can be put together in two stages and the most effective one — changing the sprockets — is the cheaper.

There are plenty of arguments for alternatives, though. People fitter than me like the simplicity of 1 X 11 systems and are prepared to sacrifice a bit of range to get an easy life, and more power to them.

It's a pity Shimano doesn't make it easier to put together a wide-range system like this. They could offer SGS versions of the Ultegra and 105 Shadow rear derailleurs, for example, with the capability to handle 11-40, 11-42 or even 11-46 cassettes. And they need to offer chainsets with smaller rings and front derailleurs that work with them. Maybe next year, eh?

Our official grumpy Northerner, John has been riding bikes for over 30 years since discovering as an uncoordinated teen that a sport could be fun if it didn't require you to catch a ball or get in the way of a hulking prop forward.

Road touring was followed by mountain biking and a career racing in the mud that was as brief as it was unsuccessful.

Somewhere along the line came the discovery that he could string a few words together, followed by the even more remarkable discovery that people were mug enough to pay for this rather than expecting him to do an honest day's work. He's pretty certain he's worked for even more bike publications than Mat Brett.

The inevitable 30-something MAMIL transition saw him shift to skinny tyres and these days he lives in Cambridge where the lack of hills is more than made up for by the headwinds.

63 comments

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roadmanshaq [45 posts] 3 months ago
3 likes

A very interesting read!

 

Are the SRAM 1x set up gravel bikes generally geared OK? I am on the lookout for a "gravel bike" to use for touring in countries with roads and trails even ropier than ours, and like the idea of a 1x on the ease of use and reliability front. For example the PX Full Monty maxes out at 42 42 which I thought would be good enough for pretty much anything bar really serious climbing. 

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jterrier [215 posts] 3 months ago
5 likes

To summarize;
Check your rear mech is as above
Shove the b screw all the way in
Fit bigger cassette
Reconfigure your rear limit screws and cable tension
Slam your front mech down a few mm
Fit subcompact chainset
Fit new chain
Reconfigure your front limit screws and cable tension.

Top job. May not work on every bike though, none of this is guaranteed, hence Shimano having such restrictions.

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vonhelmet [1326 posts] 3 months ago
1 like

I have 46/36 and 11-32 on my sram apex equipped “gravel” bike. I could do with getting the gearing a bit lower, but funds are committed elsewhere just now. I’ve already forked out for the 46/36 cross chainset which I had to import from Germany as no one in the uk was selling it.

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joules1975 [569 posts] 3 months ago
3 likes
roadmanshaq wrote:

A very interesting read!

 

Are the SRAM 1x set up gravel bikes generally geared OK? I am on the lookout for a "gravel bike" to use for touring in countries with roads and trails even ropier than ours, and like the idea of a 1x on the ease of use and reliability front. For example the PX Full Monty maxes out at 42 42 which I thought would be good enough for pretty much anything bar really serious climbing. 

That depends!

My gravel bike came 1x with 44 ring and 42 largest sprocket. This was fine on the road, if unladen, but as soon as I hit the gravel or added any load I began to struggle. Combine gravel and load and it became unpleasant. Most forest roads are easily as steep or often steeper than most tarmac roads, but with the surface being far from smooth and often very draggy due to moisture, there was no way I was going to stick with that set-up.

I decided to change the chainring for a 38t, and hey presto, sorted. On occasion I wished for even lower, but that's only on some really steep off-road stuff, and I'll just battle up those bits as otherwise it's perfect. I can still pedal at 28 mph which is plenty fast enough for the bike. If I want to go faster, I'll be on my 'normal' road bike, sticking to tarmac and riding unladen - on the gravel bike though anything over 25 mph and I just ease up and enjoy the rest.

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dafyddp [464 posts] 3 months ago
0 likes

Interesting. A couple of weeks ago, I followed the LF6 Long Distance route across Belgium on my Kinesis ATR with about 20kg of luggage/water. The route attempts to track a 'scenic' path across the region that takes in both the Bosberg and  Kluisberg not to mention miles and miles of forests and dodgy concrete roads through corn fields. I felt that the 50/43 and 33/11 combination should have been sufficient, but it was taking me all day just to cover 100km (my average speed was barely 15kph).  The heat obviously didn't help (it was touching 32° most days), but I do wonder now whether a wider breath of gears might have been wiser? I didn't think it was an option, really...

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joules1975 [569 posts] 3 months ago
1 like
vonhelmet wrote:

I have 46/36 and 11-32 on my sram apex equipped “gravel” bike. I could do with getting the gearing a bit lower, but funds are committed elsewhere just now. I’ve already forked out for the 46/36 cross chainset which I had to import from Germany as no one in the uk was selling it.

Cross chainset offers less gap between chainrings, but has a higher lower end than a normal compact . I'd suggest swapping the 36 for a 34 ring for a cheap and fast lowering of the gears.

Trouble with a 46/30 chainset mentioned in the article is that althought the mech works, it's not perfect (much more difficult to set-up to avoid chain/mech rub). The mech isn't designed to work with a ring size of 30t and the distance from the mech to that ring means the chain is further in towards the frame at the point the chain passes through the mech, meaning the mech must be allowed to move further towards the frame to stop the rub, meaning it rubs much earlier when shifting up the sprockets.

The gap between the rings in percentage terms on a 46/30 is also much bigger than on 50/34 (it feels much bigger than the numbers would suggest - I often had to shift two or three gears on the back when shifting between rings to balance things out pedalling wise).

If my bike hadn't come 1x, I would have stuck with double but gone for 46/32 to help deal with both issues.

Shimano need to produce a front mech specific to 'super compact' chainsets, and maybe a super compact chainset too, then I'd consider running such a set-up again (although I do like having my left shimano lever hooked up to a dropper seatpost ... there's another experiment road.cc could do and write an article about!).

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aegisdesign [113 posts] 3 months ago
1 like

I quite liked the setup Bombtrack run on their Beyond gravel bike.

Apex 2x10 shifters.

SRAM 42/28 MTB X5 chainset. 

GX rear, MTB X5 front. 11-36 cassette.

Gear range is 21-104" depending on tyres which is scarily close to what I used to run on an MTB 3x7 (48/36/24 & 12-28) back at the dawn of time.

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Hamster [114 posts] 3 months ago
2 likes

Suffolk, longer climbs. this does not compute. Max elevation in Suffolk is128m asl, where are these longer climbs as us local types would like use them for training.

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ericf [8 posts] 3 months ago
5 likes

Good read! More articles like this, please.

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John Stevenson [383 posts] 3 months ago
1 like

roadmanshaq wrote:

A very interesting read!

 

Are the SRAM 1x set up gravel bikes generally geared OK? I am on the lookout for a "gravel bike" to use for touring in countries with roads and trails even ropier than ours, and like the idea of a 1x on the ease of use and reliability front. For example the PX Full Monty maxes out at 42 42 which I thought would be good enough for pretty much anything bar really serious climbing. 

Everyone's tastes and preferences are different, of course, but the lack of range of most drop-bar-bike 1X set-ups puts me off.

As I understand it, SRAM's road and mountain bike rear mechs have the same pull-ratio, so if you wanted really wide 1X you could use a mountain bike rear mech and a Garbaruk 10-50 11-speed cassette.

Garbaruk also makes a long-arm cage for Shimano Shadow rear mechs, but it's listed as being compatible only with mountain bike mechs. Might be worth a try for drop-bar 1X.

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kil0ran [1170 posts] 3 months ago
1 like

Brilliant - more articles like this please!

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John Stevenson [383 posts] 3 months ago
0 likes

Hamster wrote:

Suffolk, longer climbs. this does not compute. Max elevation in Suffolk is 128m asl, where are these longer climbs as us local types would like use them for training.

Longer than Cambridgeshire (especially the bit where I live, on the edge of the Fens) isn't the same as objectively long!

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John Stevenson [383 posts] 3 months ago
0 likes

vonhelmet wrote:

I have 46/36 and 11-32 on my sram apex equipped “gravel” bike. I could do with getting the gearing a bit lower, but funds are committed elsewhere just now. I’ve already forked out for the 46/36 cross chainset which I had to import from Germany as no one in the uk was selling it.

Assuming you have an Apex W-Fli rear mech, it's rated to a 32-tooth large sprocket, but I bet it'll take 34 or even 36. (disclaimer: I haven't tried this, proceed with caution and at your own risk).

Or you could fit a GX 2 x 10 rear derailleur, which is rated for a 36-tooth sprocket.

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John Stevenson [383 posts] 3 months ago
0 likes

joules1975 wrote:

Trouble with a 46/30 chainset mentioned in the article is that althought the mech works, it's not perfect (much more difficult to set-up to avoid chain/mech rub). The mech isn't designed to work with a ring size of 30t and the distance from the mech to that ring means the chain is further in towards the frame at the point the chain passes through the mech, meaning the mech must be allowed to move further towards the frame to stop the rub, meaning it rubs much earlier when shifting up the sprockets.

Hasn't been a problem for me, but as soon as you go outside Shimano's approved parameters, the problems that arise depend very sensitively on the details of your particular bike.

joules1975 wrote:

The gap between the rings in percentage terms on a 46/30 is also much bigger than on 50/34 (it feels much bigger than the numbers would suggest - I often had to shift two or three gears on the back when shifting between rings to balance things out pedalling wise).

Good point (as are your points about Shimano needing to make a sub-compact-specific drivetrain) but not something that bothers me. It's easy to upshift a few gears with the levers at your fingertips. Back in the downtube levers days, gear gurus like Frank Berto would design gear systems specifically to avoid this problem, but I don't think anyone would suggest a return to half-step-plus-granny gearing.

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roadmanshaq [45 posts] 3 months ago
1 like
John Stevenson wrote:

Everyone's tastes and preferences are different, of course, but the lack of range of most drop-bar-bike 1X set-ups puts me off.

As I understand it, SRAM's road and mountain bike rear mechs have the same pull-ratio, so if you wanted really wide 1X you could use a mountain bike rear mech and a Garbaruk 10-50 11-speed cassette.

Garbaruk also makes a long-arm cage for Shimano Shadow rear mechs, but it's listed as being compatible only with mountain bike mechs. Might be worth a try for drop-bar 1X.

 

Thanks John - seems bonkers to me that the market hasn't picked up on this, I'm sure it'd be very popular among tourists, randonneurs and even cargo bikes.

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davidjsteer [2 posts] 3 months ago
2 likes

I have been riding a 3 x 11 set up on my Disc Trucker for the past three seasons which is also not supposed to work. Deore 22, 36, 48 + 11-40 + XT bar end shifters + XT Dynasis rear mech + Woolftooth Tanpan, all work brilliantly for me. I expected accelerated chain wear but have not seen it. Lost a tooth off the 40 sprocket on "The Distance" but didn't notice until the post ride wash down.

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darrenleroy [305 posts] 3 months ago
3 likes

Interesting feature. Could we have more of these please? Perhaps one on understanding gear inches for idiots.

I posted a while ago about needing to increase the range before heading out to the Pyrenees next month. I have a 10 speed 11-25 cassette on the rear with a compact chainset. I have an old Record rear derailleur that won't extend as low as 32. I don't  understand gear inches and the online tables mean create more confusion as I don't have an engineering degree.
What size chainset should I replace mine with to get the equivalent of a 34-32 (or lower)? 

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Augsburg [29 posts] 3 months ago
2 likes

Great post and so true about how the major component manufacturers ignore the needs of regular riders.  When I lived in hilly Seattle, on the west coast of the U.S., I had to set up all my bikes with gear-inches in the low 20's.  In cities like Seattle or San Francisco, you can have climbs of a mile and more that average a 10% grade, and shorter hills with grueling 18 to 20%. grades  I  was able to achieve low gearing, including with a couple of IGH bikes.  

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John Stevenson [383 posts] 3 months ago
1 like

roadmanshaq wrote:

Thanks John - seems bonkers to me that the market hasn't picked up on this, I'm sure it'd be very popular among tourists, randonneurs and even cargo bikes.

It's long annoyed me that component makers only do product development with elite riders.

I want to head up PUFFIN* Skunkworks, providing product development testing by people who aren't even fit enough to be called MAMILs.

*Alexei Sayle's Pathetic Unfit Fat F*ckers In Nappies

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John Stevenson [383 posts] 3 months ago
2 likes

davidjsteer wrote:

I have been riding a 3 x 11 set up on my Disc Trucker for the past three seasons which is also not supposed to work. Deore 22, 36, 48 + 11-40 + XT bar end shifters + XT Dynasis rear mech + Woolftooth Tanpan, all work brilliantly for me. I expected accelerated chain wear but have not seen it. Lost a tooth off the 40 sprocket on "The Distance" but didn't notice until the post ride wash down.

Chapeau! That's a hell of a gear range. I run 48/36/20 & 12-30 on the tandem, which also isn't supposed to work.

Ignoring Shimano's rules FTW!

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Scottish Scrutineer [27 posts] 3 months ago
1 like
John Stevenson wrote:

Assuming you have an Apex W-Fli rear mech, it's rated to a 32-tooth large sprocket, but I bet it'll take 34 or even 36. (disclaimer: I haven't tried this, proceed with caution and at your own risk).

 

You can run a 11-34 cassette on a Rival Wi-Fli. I have that on my Planet X ProCarbon. I tried it on my Equilibrium with a 105GS cage, but the B-screw wouldn't adjust far enough as clear on the 34 cog. Haven't tried the latest 105/Ultegra shadow RD though.

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John Stevenson [383 posts] 3 months ago
1 like

darrenleroy wrote:

Interesting feature. Could we have more of these please? Perhaps one on understanding gear inches for idiots.

I had a stab at that here: https://road.cc/content/feature/171317-beginners-guide-understanding-gears.

If that doesn't do the job, come back to me here and I'll have another go.

darrenleroy wrote:

I posted a while ago about needing to increase the range before heading out to the Pyrenees next month. I have a 10 speed 11-25 cassette on the rear with a compact chainset. I have an old Record rear derailleur that won't extend as low as 32. I don't  understand gear inches and the online tables mean create more confusion as I don't have an engineering degree.
What size chainset should I replace mine with to get the equivalent of a 34-32 (or lower)? 

Assuming you have a compact chainset, then you have a 37-inch low gear. The 34/32 you'd like is 29 inches.

As far as I can find out, your Record rear derailleur will shift up to a 29-tooth largest sprocket, but only the medium-cage version will be happy taking up all the chain slack generated by an 11-29 cassette and a 50/34 chainset. If that's what you have, then you're good to go. That gives you a 32-inch low, which is some 16% lower. The gaps on your 11-25 cassette will be quite small, so that will feel like it's one or two gears lower.

If you want a lower gear still, you're going to need a subcompact like the FSA mentioned in this article. That would give you a 30/29 low, which is 28 inches. In terms of how that'll feel, it's two or three gears lower than what you currently have.

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John Stevenson [383 posts] 3 months ago
0 likes

Scottish Scrutineer wrote:

 

You can run a 11-34 cassette on a Rival Wi-Fli. I have that on my Planet X ProCarbon. I tried it on my Equilibrium with a 105GS cage, but the B-screw wouldn't adjust far enough as clear on the 34 cog. Haven't tried the latest 105/Ultegra shadow RD though.

I've seen accounts of people using 34 and even 36 sprockets with the 105 5800 GS rear mech, but these things are very dependent on the exact configuration of things like the derailleur hanger. 

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dmk [3 posts] 3 months ago
2 likes

Shimano 11x34 with Acera triple (26/36/48).

There you go. Now you're riding a Giant Escape.

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Nick T [1164 posts] 3 months ago
1 like

How did the mech handle all the excess chain with a monster cassette like that? I’d imagine it was hanging like the doors on a Lancaster Bomber in any sort of small-small combo

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Bmblbzzz [231 posts] 3 months ago
1 like

On one bike I have a 44/28 chainset with a Tiagra 9-speed f.d. I think it's 4500 series mech, anyway it works fine. I probably wouldn't go any smaller with a road mech, but as numerous people have already said, it does depend on the configuration of your bike. Used with an 11-32 cassette this gives me a lovely low granny gear of around 23" while avoiding large gaps between gears, and still keeping a high top gear of 108". Which is high enough that I only use it about twice a year, ymmv. 

With this set up I not only find hills much easier, I reckon I often get up them quicker by spinning a low gear than when I had to grind a higher one. And my knees are probably going to thank me for it too, especially when I get a bit older.

I'd like to add my voice to those saying how useful and informative this article has been. More please! 

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gonedownhill [207 posts] 3 months ago
0 likes

Slightly off topic, but has anyone ever converted a ss Shimano derailleur to a GS by swapping the cage plates? You can buy 6800 plates from sjs cycles, lot cheaper than a new derailleur.

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John Stevenson [383 posts] 3 months ago
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Nick T wrote:

How did the mech handle all the excess chain with a monster cassette like that? I’d imagine it was hanging like the doors on a Lancaster Bomber in any sort of small-small combo

It's been fine. Shimano really have been very very conservative with the stated capacity of the RD-R7000GS.

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John Stevenson [383 posts] 3 months ago
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gonedownhill wrote:

Slightly off topic, but has anyone ever converted a ss Shimano derailleur to a GS by swapping the cage plates? You can buy 6800 plates from sjs cycles, lot cheaper than a new derailleur.

The main body is the same, so that should Just Work™.

Parts diagram here: http://si.shimano.com/pdfs/ev/EV-RD-6800-3608E.pdf

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Bmblbzzz [231 posts] 3 months ago
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gonedownhill wrote:

Slightly off topic, but has anyone ever converted a ss Shimano derailleur to a GS by swapping the cage plates? You can buy 6800 plates from sjs cycles, lot cheaper than a new derailleur.

Don't know. First I've heard of the possibility – but I'm making a note of it cos it sounds good!

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