It's interesting when you and some others in this forum made comments that my pattern jumps are huge. But did you guys know that touring bikes with 7 speed system 13-34 with a triple 46/36/24 that were sold many years back with some of the best brand names had 21 gears and the spread is the same as my current 2x10? I toured with that for many years on a Shimano RSX system both on my past Norco Alteres and my past Bike Friday New World Tourist. I'm sure some of you had toured with a 21 speed system yourself. Don't you find those big jumps impeding your touring pleasure? There are many people right now who are still touring with only 21 speeds. Touring with my Masi is no different than touring with my Norco or my Bike Friday.

Like I said before, I don't really care about gearing as long as I have a working set of low gears, middle gears and some high. It's there to be used, but there's no need to worry why and what it can't do for me.

Speaking of big jump between 42T and 24T has to do with your crankset. If your crankset is well made with well precision craftsmanship (not the new cranks these days), then 16 to 18T jump would be fine and 20T would be the max with some trimming. Jan Heine tried ever higher jumps too. The problem is with the modern crankset. 100% quality control is no longer practice in house. Most of the quality control is now placed on the hands of the consumer (which is you) since it is cheaper to replace a defective crankset rather than hire guys to check every single crankset for chain wobble. But not all consumers are equally as knowledgeable on how to determine whether the cranks are defective or not unless you have a working knowledge. This way, the manufacturer can get away with many more sub-standard quality components which helps them keep the cost down and more profits in their pockets! Since the frame flexes during riding and especially during touring, any minor wobble can cause chain rubbing on the derailleur plus difficult gear shifting with "large" tooth differential! In my case, I'm running an old school Sugino Super Maxy crank which is known for its quality and workmanship and
there is no chain wobble noticeable. The shifting between 24T to 42T is good but minor trimming is required but that's ok since my Tiagra shifter can do this. This is in contrast to my P.O.S Bontrager triple crankset on my Trek 5000 bike where shifting from 30T to 39 hesitates much more than my Sugino crankset and almost require some trimming! There is chain wobble with this garbage crankset! I'm tempted to just throw this P.O.S junk and replace it with a triple Rene Herse crank from Compass Cycles as it is considered one of the best cranks out there. If I don't have this old school crank handy for my Masi, I would not hesitate buying a Rene Herse double crank.

By the way, the Rene Herse crank takes a 70mm BCD for all 3 chain rings. Which means, you can do half-step on the middle high or half-step on the granny low which is what I want, when I have the money ofcourse!

Go run the chart. A 46/36/24 does nave the same range. No argument. But you seem to keep missing the spread. A 46/36/24 has a 28% difference between the outer and middle ring. It has a 50% jump between the middle and inner ring. That 50% jump is highly noticeable when you shift. I find that I have to speed up my cadence significantly when I change to the inner ring. But, since I usually do it when I'm starting a climb, the bike slows quickly and my cadence comes down to a more comfortable rate.

But for a 45/28, there is a 60% difference between the two rings. You also commented above that

With the pattern of the compact double you are using, you have not just a double shift to smooth the transition from ring to ring but you have do a shift off the outer ring and shift the rear 3 times to get to a gear that isn't 60% different from the one you were in. For example, say you were riding in the 45/24 combination (a 51" gear) and you had to downshift. You could drop straight to the inner ring and you'll be riding in a 31.5" gear. The next gear closest to the 45/24 combination is the 28/17 or 3 upshifts. On the other hand, with the 46/36/24 7 speed, you could be riding along in a similar gear of 46/24 (52" gear). If you shift off the outer ring to the middle ring, you end up in a 41" gear. It might not be the best gear but it's not a 60% change. The change is smoother without double shifting.

I have no problem with you riding whatever you want. But you can't just look at the overall range of the cranks and say that they are just the same. The math just doesn't support that statement.

Hmm, I did run it through Sheldon Brown gear calculator site based on a 700x38c setup and 170mm cranks.

Below are the gear inches for 46/36/24 with a 7 speed K 13-34 cassette (on my past Norco Alteres)
(46) 96.7,83.8,73.9,62.8,52.4,43.3,37.0
(36) 75.7,65.6,57.9,49.2,41.0,33.9,28.9
(24) 50.4,43.7,38.6,32.8,27.3,22.6,19.3

Below are the gear inches for my 42/24 with a 10 speed 11-36 SLX cassette (on my current Masi)

(42) 104.3,88.3,76.5,67.5,60.4,54.6,49.9,44.1,35.9,31.9
(24) 59.6,50.4,43.7,38.6,34.5,31.2,28.5,25.2,20.5,18.2

Notice that on the lower gears, my 2x10 11-36 is superior than the 21 speed 3x7 setup due to the 7 gear spacing on the 7 speed cassette, which is providing the wider gear ratios.

Typically, riders shift BASED on pedal feel not on some strategic gear chart formulation. If the pedal becomes harder to push, they shift down a gear until they can't shift and then they shift to the next easier chain ring. You made it sound like every cycle tourist shift gears like a pro Tour De France rider or Michael Andretti driving a race car. Most cycle tourist do not attack a hill like a fast roadie would do. Yes, some do this but this is not the norm.

With the 21 speed 3x7 setup, they will have to shift 2 times to get to the granny 24T, whereas with my 2x10 system, I only shift 1 time.

Is there a reason why I would want to shift from a 42/19T (60.4") to a 24/11T (59.6") just so that I get a nicer ratio?!?

If you examine my 2x10 gear chart, it has just about all the gear ranges of a 3x7, except the middle to lower ranges have a tighter cluster of the 10 speed.

Even if I shifted to my lowest gear inches 42T/36T (yes cross chaining) which is 31.9", dropping it to a 24T would simply put me on a 18.2" gear, hardly causing me to fall over face flat either. Did this a few times this year in this combo no problem climbing grades starting from 4% going up to 20%+ on Saltspring Island in British Columbia. Usually, I bail from 44" gear when I know there's a tough climb ahead to 25" and then spin and then shift down when it's necessary. Again, I see your point where I will have a 60% gear inch gap, but that's toward the end of the lower gear ranges, something I don't mind bailing to. It's called granny gears for a reason! I have a working double bike and a triple bike with similar gear ratios and I just don't see a big difference in gear shifting. My setup is based on a stock 7 speed touring cassette and a 10 speed SLX cassette (both are available stock) which others I'm sure are using as well.

At the end of the day, touring is about riding the bike and making it work. Most people ride with a standard crankset modified with a 26 or 24T granny off their 52/42 or 46/36T trekker cranks and they did just fine on any terrain. Everyone always want more gears. The guy who has 54 gears wanted even more because he thinks he needs more just the same as everyone here in the world would love to have more money.

You can tour with a triple or a double and as long as you have the highs, medium gears and enough lows to climb Mt. Everest, then the issue here is what do you prefer to have. Triple or double.

But I think some people really misses the real point and that is, a triple crankset was conceived to open up the biking interest to a wider audience by bringing in "LOWER" granny gears for people who don't have the muscles to pump up a hill with a 53T/13 or 55T/11T. In the 70s, the lowest acceptable granny was 27". See how times has changed this. Bikes today have lower gears thanks to the compact double, mountain trip and the new mountain road gearing from SRAM and the technology is there to be used. Some people insist to be luddites in the triple era and that's fine. Some of us are just making aware that you can have a double setup with lower gears and decent highs for touring. Ultimately, it's the rider who chooses the system.

Cheers.

Let's look at this from the stand point of speed at 90 rpm and go back to my example. With a 3x7 system in the 46/24 gear at 90rpm, you'll be traveling at 14 mph. When you shift from the outer ring to the middle ring, say in preparation for a hill, if you maintain 90rpm the 36/24 combination give you a speed of 11 mph. You could maintain the same speed by increasing your rpm to 120 if you wanted to or had to. But the speed differential is small enough to that you'll slow down quickly enough and can maintain a comfortable 90 rpm.

With the double and a 10 speed cassette, in the same 24 tooth cassette cog, you'll be doing 13 mph. Changing to the 24 tooth inner drops the speed roughly in half at 90 rpm to 7mph. If you increase your rpm to 120, you'll be able to develop 10 mph and you'd have to pedal somewhere around 140 rpm to get to 12 mph. I can do 120 for a little while but 140 is just way too fast and too uncomfortable for even short times. About your only option is to let the bike slow down to around the 90 rpm range and just eat the loss of momentum.

If you go the other way...an upshift...let's say that you are tootling along at 12 mph at 90 rpm in the small ring for whatever reason (this will work with any speed in any gear combination but let's just pick one). That's going to be a 24/14. You upshift to the outer ring. If you could maintain the 90 rpm...you won't be able to...your speed would jump to 21 mph. In reality, you rpm would drop to somewhere around 50 rpm. That's mashing range. To get your rpm back up you'll have to either drop back down to the inner ring or make 4 downshifts on the cassette.

With the 3x7 system, you could be rolling along at 11 mph at 90 rpm in the 36/24 gear, upshift on the front to the 46 and you'd be at 14 mph while still maintaining an rpm of 90. In my opinion, I'd prefer a single upshift on the front chainring to an upshift on the front chainring and 4 downshifts in the back.

While the 10 speed system might be marginally better than an antiquated 7 speed system, when it is compared to a modern system or even to a triple crank and a 10 speed cassette, it falls far short. A 42/32/24 (or 22) 10 speed system would be almost ideal. It splits that 60% difference between the compact nicely in half.

I too go by pedal feel but I don't know of anyone who downshifts until they can't downshift anymore. Most people will learn that downshifting until you hit the largest cog on the cassette leaves them in a bad gear combination where further downshifting only leads to having to do high rpm to maintain speed. A bike drivetrain isn't linear like a car's drivetrain is. It doesn't take too much time to learn the difference and how to make better use of the bike's gears. You don't have to ride like you are in the Tour de France or like the bike is a car to appreciate a good gear pattern. My objection to the compact double idea is that the gear pattern are like a linear gear pattern in a car...just really poor versions of it. If you look at the speeds, the gear inches, the gear ratios or whatever is you favorite flavor of gear calculation, the compact double system is like two entirely separate drivetrains. It's got a high range and a low range and nothing in between.

That's the point to any triple crank, isn't it. You, with a double system, can only shift one time to go from high range to granny. It's a big 'KACHUNK!' and it goes from fast to slow. A triple has steps so that the rider can choose gears in between high and granny to fit the terrain they are riding.

Yep. Tighter ratios than a 3x7. But not tighter gear ratios than a 3x9 or a 3x10. Just fewer choices.

Ummm... Sure. And my 1x19 gearing system would kick both of their @$$e$ (as 3*7=21, 2*10=20, and very surprisingly 1*19=19).

There was a time when I worried a lot about gearing. I thought I needed super low gears and worried that I wouldn't get up hills with my touring load. But I lightened my gear load and got a bit fitter and now I really couldn't care less about gearing. I've toured using only 2 gears (67" and 39") and on a compact crank 2x10 with a 104" to 37" range and on a 2x9 with a 103" to 21" range; I enjoyed each trip. There is no right or wrong here; you don't need a triple to tour, but if you like triples go ahead. However, once you leave behind the touring dogma of what bike and gearing you need to tour successfully it opens up a range of bikes that are a lot more fun than most touring bikes.

You are correct that there is no right and wrong here but please respect others choices as well. Also respect others abilities. Your post has lots of loaded words in it that can easily be interpreted as insulting or holier-than-thou. Things like 'got a bit fitter', 'you don't need a triple to tour', even 'touring dogma' are all loaded terms.

I am not 'unfit'. I don't think that anyone who uses a triple is 'unfit'. I don't even consider anyone who posts here is 'unfit'. We bicycle tourist do an activity that not 1 in a thousand Americans do. By its very nature, bicycle touring requires at least a small level of fitness that is higher than the general population.

You may not want a triple for touring. That's you and fits your style. I did a 24 ride days and 1200 mile tour this summer through the toughest terrain (81,000 feet of climbing) that I've ever encountered and I appreciated my triple every single day. I also appreciated the gear I carried everyday. Maybe my load could have been lighter but that's my choice. But with 81,000 feet of climbing, including 5000 feet over 14 miles on the second day, I'm quite happy I had a triple and a very low one to boot.

You may like the minimalist approach to touring...more power to you...but I don't want to make the kinds of sacrifices that you are willing to make just so that I can use a double.

my touring bike (in progress, story of my life) is going to have a double. Not because I'm particularly strong, but because I don't have a big chainring. The truth is, I don't use super high gears. My crank has a 42 tooth big chainring, which doesn't sound like much but a 42x11 is a higher gear than the 52x14 we all used BITD. I live in the mountains and I rarely find a use for the 11 in the back. This is a pretty common combination on current mountain bikes. My small chainring is a 24 or something like that, but if I ever go touring I'll have something like a 36 in the back. I wonder if this is what the bike shop person was suggesting to the OP. My LBS suggested I go with this combination. My MTB may have a single chainring with the SRAM system. That seems like a pretty good idea.

You sound a lot like the way I thought about this. I found 42t was big enough and found 24t was small enough. I saw 11t wasn’t needed and 36t was. So as a double I was fine with 42, 24 x 12-36, strongly putting me in the double camp until I added the 45t and I still say I have a double just a 45,42 + granny. Talking about transitioning between the 42 and the 24 its not silky smooth like the 45 and the 42, but it’s not that bad and I don’t have a Rene Herse. I go to the granny when I need something lower than 31GI dropping to the granny range. Everyone talks about the lowest gear but I like the spread of GI I get off that wide cassette. Around here we have rolling hills and having that range is more important than the absolute lowest gear.

I think there is a difference in a double and triple in the conventional way and a double +granny or a single +granny I would call the 42,24 a single + granny. That might be where some of the confusion is coming from.

There is an evolutionary process most go thru and it is so based around individual needs. There are some serious bike tourist here and also a lot of folks that have touring bikes and are more of the weekend warriors getting started touring. Fitness is important but shouldn’t discourage anyone from giving touring and touring bikes a try. I sometimes worry there are a lot of lurkers here thinking about doing a 100 mile weekend tour or even shorter and they are not sure if they want to jump into this. I read nuns philosophy a little different and would say a touring bike has such a wide range of gears just about anyone could feel safe taking off with a good deal of load on the bike and average abilities and get from point A to B and back over some mild terrain and have a lot of fun doing it. I’m quite happy chugging away in the gear that feels right for me and time is the great equalizer half the speed, just plan on twice the time or half the distance. At least you are moving.

The bike shop co-op I go to already know this. It is a common request by people who own cross bikes with double shifters and 10 speed at the rear and a number of other shops I know around here know this also, thanks partly to Harris Cyclery for suggesting a 9 speed Deore rear derailleur with a longer B bolt is key. 110/74BCD crank is common and you can get chain rings in different sizes in 110 and 74 BCD as well. The double route is cheaper because the main cost of upgrading the double to a triple are the shifters and when you have a 105 or an Ultegra, few would want a Tiagra or Sora to replace them as triples. However, typically people put a 36 or a 38T rather than a 42T. With a 36T and 11T, your highest GI is 89" which is plenty enough for touring. But again, others will say otherwise. It's like saying you put way too much sugar in my coffee and cream and made it way too sweet. But another person will say it's just right or others will say it's not too sweet. This then becomes more of a personal opinion. But Harris Cyclery and Sheldon Brown had been suggesting anything higher than 90 GI is usually not used for most people touring and they are basing this on sales and general requirement from their customers.
One must separate between personal opinion and real needs from most customers.

Other than that, there are a lot of triple Luddites who are opposed to this. It's a normal attitude when sign of progress threatens the foundation of why the triple came to be. When the triple came out, it too received a lot of flak with strong riders mocking people who ride triples as weak cyclists. But that's just an ego thing, rather than acknowledging triples bring more diverse people who not necessarily have the strength and power into recreational cycling!!

But I sense, it's not what the triple can do, but their opinion must be put as being right even though it sometimes make no sense. And this seemed to be what's happening.

I think we are not debating gears, because I feel you think my gears are too high still for touring. This is simply a fitness issue. Every rider has different fitness level going into touring and typically the bike shop who sells a touring bike and knows about gearing ratios will look at the current bike the OP is riding and determine where the wear level on the chain rings and cassette. If the big ring isn't even close to even being worn out and that the middle ring and small ring teeth are shaped close to a shark fin, what does this suggest? The rider is needing more higher gears?!? But if the reverse is true and the 46T or 53T chain ring are worn more as well as the 42T or 36T and the 30T granny or 26T are barely touched. What does this suggest?!? The rider needs more lower gears?!? In touring, you would need more lower gears but that depends on the terrain and rider fitness. Most smart shops will want to see your current ride and determine the appropriate gears. The OP went to the shop and the owners suggested a 2x10 system rather than a triple. You don't suggest this unless you're sure you can make your customer happy, because suggesting other than the norm triple and if the customer isn't happy with the advice, the owner can become liable. If and when the 2x10 isn't suitable for the customer, the owner may have to install a triple possibly on his own expense. Why would a store owner be so stupid?

It's obviously now getting to a point that we are discussing what gearing we like and is no longer related to the gear ranges a 2x10 system can offer rather than a triple. As I said before, a less fit or a super strong cyclist would benefit from a triple without loosing the high gears either for ego's sakes or wanting to bomb down a hill maybe once in a blue moon with a 110 or 122" gear, because a 32/24T 2x10 double would be too limiting. A 36/24, 38/24 and 42/24T provide a good compromise with ranges similar to a triple while loosing 1 or 2 higher gears.

Like someone who said it correctly here. It's an evolutionary process and nun had said it well -- eventually, you don't even care which gears you're in or you're using. All you care about is being able to get from point A to B and having loads of fun.

Cheers.

Okay gentleman, while I must say I've been aggressive in this pissing match, let us get back to answering the original question. OP is looking at a 10 speed rear drivetrain. Plain and simple, many of you who are so steadfast in running a triple are also running 8 speed drive trains. as for the talk about cadence when you shift rings on a triple, I don't understand why that individual doesn't double shift. That is one thing I do enjoy about a triple, generally speaking if i"m in my middle ring and a big hill is coming up, I can shift down to my granny but shift to a smaller cog in the rear at the same time and keep my cadence in a good place but then as I hit the hill I don't have to worry about shifting the front, I can just drop down the cassette. Same thing when approaching a downhill if im in the middle ring, shifting right up to the big ring might be too much gear but if I simultaneously shift to a bigger cog in the rear, I'm still at a smooth cadence.

With doubles it's different. With doubles, you tend to need to use more of the cassette and when it is time to shift to a bigger chain ring, you may have to shift multiple gears in the back to be right where you want to be. One nice thing about doubles is cross chaining is far less of an issue. I cross chain all the time on my double bike when riding with my racier friends on aggressive training rides because I don't want to risk dropping the chain shifting to the small ring up front. My double drive train has no issue with going big/big or small/small combo. I don't even have to use the trim feature on my front deraileur although it is there if the need arises. A lot of the people I know that ride triple cranks ride them with a 28 as the largest cog in the rear and occassionally a 32 and never a 36 If I'm not mistaken a 36 tooth isn't even available in 8 speed cassettes either and the ones that have a 34 it's more of a "bailout" to the 34 so you have a massive jump from 26-34. So for a lot of people 10 speed drivetrain means you are easily able to get yourself a 32 and a 36 tooth cog while keeping reasonably tight spacing. So here is the way I see it, most bikes that are sold as triples, tend to not come with as wide of a cassette standard. Bikes sold as doubles often do have a wider cassette on the back. So yes, if you want super ultimate range, get a 22/32/44 mtb crank and run a 11-36 10 speed cassette. but in reality, most people running that crank end up with an 11-28 and part of that is that a 22/36 isn't very useful to many people. Many people would just as soon walk than actually use a 22/36 combo that only gets them 5mph at 90rpm cadence and 2.9 mph at 60rpm cadence.

In conclusion, yes, the maximum range you could get is with a triple and 10 speed wide range cassette, however, that does not mean you will find all of those gears very useful and if you setup a double crank correctly, you will find that you will have the same range as many peoples triple setups and not be at a disadvantage.

10 speed wide ratio cassette , something that functions as a 10 by 1 so that ring not really big, since
the cassette tooth counts are small .
then a big drop to the 2nd bail out for mountain ascents , for the granny gear
The 'big' ring centered in the chainline , like the middle of a triple.

New; Sram has a 11x1 MTB kit.. top is 10t, bottom id 42t, 2nd is the 36t


my favorite now is a 7 by 2 , internal gear hub , by Rohloff..
the 7 speeds are run through twice in 2 ranges.. 14 in total

Something I learned a long time ago was that when working hard all day riding (loaded or unloaded) keeping my cadence at what my legs are happy at is really important to how my legs feel at the end of the day. Therefore shifting so that I keep my cadence and output force within a close range makes all the difference. In my opinion having less of a jump between chainrings is easier in this regard because as cycco explained well, you dont have to do the 3 or 4 up or downshifts when monkeying back and forth between two chainrings that have 16 or more tooth differences.

In terrain where one is shifting a lot because of rolling terrain, or constant steep up and downs, it is because of this that I appreciate a triple, just because there is less multishifting. I certainly contend that with modern brifters, multiple shifting is pretty fast, but its nice to not have to do so many quick shifts.

Think too of how a loaded semi truck has their gear ratios really close together, its the same with us--if we have a lot of weight on a bike--as I have said, going light in your gear really makes a difference in all of this but its very common for a lot of beginning tourers to have too much stuff.

I would really like to try riding a compact to see how a compact of maybe 16 or more tooth difference is with modern shifters, although I strongly suspect that I would tire of the regular 2 and 3 up/downshifts, especially if I have 30-40lbs of stuff.

this is exactly what I am trying to describe, I do this all the time with my 9 speed triple, and exactly why I like it. Its fast, usually one quick shift at the rear along with the chainring change and bingo, as you say, your cadence is good and you just have to dingle up or down the cassette. And from my experience with the Tiagra fd, it shifts great and is consistently great on a triple, so I cant complain ever with shifting.

yep, I mentioned xx1 earlier. it's too costly for many people at the moment but if they trickle the technology down it could really work nicely for a lot of applications. Some people who don't like xx1 are dissappointed that they didn't go all the way down to a 9 tooth cog. There are some people jury rigging cassettes and fitting them with 9tooth cogs in the mtb world as well.

People can chose whatever they like, no right or wrong. When I mentioned getting fitter I was talking about myself, not implying anything about the fitness level of others.

Chill

seing 9 and 10th tooth cogs mentioned, heres a question for all of you. I find that on both my bikes that have 11 cogs, I dont use the 11s that often and a big part of that is because whenever Im in them, it feels "crunchy" slightly. Ive always assumed its because of the tightness of the chain over so few cogs. I mean I use it when I have to, moreso on the mtn bike with the 42/32/22 on downhills as I get into the 42/11 fairly quickly, but I generally avoid it in going up to the next chainring when I can (never go into it in the granny)

Do others feel the same? I dont know if its my rd setup that does this, or if in fact it is the chain being on such a small diameter cog with so few teeth. Just as cross chaining can produce a sound from a chain that seems to say that it is being worked harder, it seems to me that on a 11t it does also, and I assume a 10 or 9t even more? I guess being in it for short periods is never going to be an issue, but I do know that some riders may go onto it often, and I wonder if it shortens the life of a chain?

You are still more efficient riding at this rate than walking!

I think some of us have reached the point of: The narcissism of small differences.

"The need to distinguish oneself by minute shadings and to insist with outsized militancy on the importance of those shadings." Freud

When 9 and 10 cassettes are mentioned we're referring to the number of cogs in the cassette not the number of teeth on a cog.

When I went to the 45,42,24 and had that 45 tooth ring in line with my smallest cogs I noticed a big difference the straighter chain line made. By that time I no longer had an 11t but I notice what you are saying even on my 12t. This change has really made me more aware of chain line and how it smooth’s things out. As fietsbob posted make a double from a triple crank and get the big ring lined up in the center. That’s also why I prefer a triple as the small granny is lined up with the largest cogs my half step big ring 45t is lined up with the smallest cogs and my most used ring the 42t is lined up in the center of the cassette on the most used cogs.


It’s funny how things change over a year ago I asked if anyone knew of a cassette with a 42t large as I was playing with the numbers and wanting to keep some larger rings and get away from the real tiny cogs. All the answers I got were pretty much there is no need for anything bigger than a 32 all I had to do is go with smaller rings and save weight.

Again, loaded words. Just because you don't agree with me...nor I with you...doesn't give you the right to be insulting. I've not attacked you personally. I have addressed your ideas but not said anything about you at all.

We are debating gears. You aren't understanding my point. I don't think your gears are too high for touring. Your high and low are okay...I'd go lower but to each his own. Why I am saying is that the double systems have bad arrangements. They are linear without having the ability to use that linearity. They are two separate ratio sets that have little to no overlap. What overlap they may have isn't easily accessible. Your comments above that a tourist will shift until they can't shift anymore then change chainrings is about the only way to use a double system...as currently configured. It is, essentially, a 10 speed with granny.

As for setup, I don't agree. You have it backwards. A shop owner should set up the bike as a triple. If, at some future date, the customer wants a 2x10 (or x9 or x8 or etc.), it's easy enough to remove a chainring. Going from a double to a triple is an expensive proposition..you'll need a new shifter, a new crank and a new front derailer at a minimum... and no shop owner should be liable for paying for the conversion.

Still talking about gearing systems. A 2x10 offers the same high and the same low...or at least a similar low and useable(ish) high...but the steps in between just aren't there. You may not like to bomb downhills and I respect that. Your choice. Please respect my choice as well.

As said above, 9 and 10 speed cassettes are different from the cogs on them. That said, I suspect that the 'crunchiness' you feel may be a misalignment of the derailer in the high gear. The limit screw may not be set properly or the cable may be tight so that the chain grinds a little on the cog while pedaling. You could also be hitting something...rack or fender screw...when in high gear. Check both.

The life of the chain when cross chaining is determined by the length of the chainstays and which chain ring the cross originates. Less with a 42T because more teeth are supporting the chain (stress evenly distributed through more teeth) as opposed to a 24T where less tooth are supporting to a 11T. Touring bikes have the longest chainstays which makes the chain angle less acute, so it lessens the wear compared to say a road bike or a triathlon bike. A triathlon bike has the shortest chainstays, because they have to make the rear wheel be as close as the seat tube for aerodynamic purposes and to allow riding geometry to allow being closer to the aerobars. Chain will wear sooner on a triathlon bike than a touring bike if the rider cross chain often. This is a common complaint from people coming from a touring or rando bike and into a tri bike as many of them probably started triathlon this way. Their cross chaining habits migrated into their tri bikes with only 2 chain rings.

Having said that, as long as you have a good chain line, the cause is not your rear derailleur. The cause is with your front chain rings or front crankset.

Most chain rings these days will have a slight wobble. 100% quality control is pretty much non-existant today in many industries including bikes as it is expensive to keep good quality because you need to keep paying QC people in house. So they make you, yes the consumer, as QC people. It's cheaper to replace a defective chain ring or crankset free of charge rather than go through every single chain ring or cranks. It's the norm now. Besides, how would you, as a consumer, know the products are sub-standard quality. See, they can get away with many of these products out in the market! In the old school days, you can see mounting marks on the chain ring bolt area and the BB slot of the cranks to show that they actually mount it to a dial indicator gauge to see chain ring "RUN OUT". Today, you are doing this. It sounds to me that you have what is called "chain ring run out". To solve chain ring run out with the not so flat chain ring, they use 4 and 5 pattern bolts to hopefully pull all the sides in to make the ring flat. But that's cheating and rarely provide a good result as your experience seemed to indicate.

Chain ring wobble is a pretty big issue with cross chaining because it really does not leave a lot of room between the front derailleur cage and the 11 cog on the 42T chain ring if you adjust the FD limit screw. If you adjust this, then shifting to the middle chain ring may not be smooth, but if you don't that the chain rubbing noise in a form of crunching noises will annoy you. Keep in mind that your frame flexes a bit too and that just compounds the problem. Most people avoid this combo, except me going downhill. Another problem with chain ring wobble is the transition between small chain ring to a bigger chain ring that has more than a 10 tooth difference. If the chain ring wobble and if you have a larger tooth differential like a 18T such as mine, the bigger the difference the harder it is to shift because the larger area of wobble prevents it from catching the ramp as opposed to a small tooth differential like what Shimano and others recommend which is 10 tooth. So now you know what the industry recommends only up to a 10 tooth difference between chain rings.
I use my old school crankset and old school chain rings I have on my touring double, there is no chain rubbing or hesitation in shifting even if I have a 18 tooth difference between 42T and 24T.

To solve your problem, either switch to an old school crank of the 70s and 80s and chain rings in good shape of that era as their tolerances are much tighter or go for better cranks from T.A and chain rings from T.A or a Rene Herse crankset from Jan Heine of Compass Cycles. As the old saying says, you will always get what you paid for. To be sure if the rings are flat, you should have a flat metal slab and a dial indicator gauge handy. The bike co-op I frequent in has those! Since chain rings wear much longer than a cassette, it would be a good idea to get these rings you can put on the cranks.

Same principle with a tire wheel. Unbalanced wheel compared to a well balance wheel. Which is more stable and create less noise?

more reasons why a double is quite doable for touring. https://www.pinkbike.com/news/General...Look-2013.html