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So I went to a bike shop to check out the options that I could buy and came across this board that has the gear using system explained for beginners (I guess?).

enter image description here

Is it not literally suggesting cross-chaining? The bike I'd most likely buy will have Shimano tourney derailleurs, both front and back.. Is this the best way to go about using the setup? The setup is a 3×7 and would be used mostly on flat roads. I'm also thinking about removing two of the chainrings since only one chainring makes more sense. (probably keeping only the middle). Say, I make it a 1x setup after removing two chainrings, (keeping just the middle one), will I still meet with cross chaining?

Yes, I've looked at options that have a 1x setup, but they aren't very reliable, and most of them have cheap suspensions and cheap disc brakes on them, both of which I want to avoid.

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    Some cheap options do have 1x and a cheap rear derailleur, but overall, the most expensive mountain bikes use 1x. Or actually almost every high-end MTB uses 1x. But with a good rear derailleur with 11 or 12 speeds and with good quality other components. But they are not Tourney, they are Deore or Deore XT. Tourney is a very cheap derailleur and a sign of a BSO, I suggest to look at real MTB grouls like Alivio or Acera. They won't come as 1x but as 3x8 3x9 2x9 and similar. – Vladimir F Aug 29 '20 at 6:25
  • Anything that is available and has a 1×8 or above configuration that's available around costs at least $450. I've only got a about half of that. 😶 – Timon Aug 29 '20 at 6:49
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    “I'm also thinking about removing two of the chainrings since only one chainring makes more sense.” – Why would you think that? You lose a lot of gear-range and gain nothing except a little bit lowered mass, and especially on flat roads that's hardly significant. Yes, some points can be made in favour of a purpose-built 1× system (though I personally will choose 2× over 1× whenever I have the option), but you won't get those if yours was constructed as 3× and you just cripple it down to 1×. – leftaroundabout Aug 29 '20 at 8:23
  • @leftaroundabout I wanted to keep less of a hassle to maintain the bike.. I mean, a 1x drive train would mean less need for maintenance than a 3x, isn't it? My logic here is that if there are fewer components, there are fewer parts to maintain and hence easier. Isn't that so? – Timon Aug 29 '20 at 10:53
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    While there are benefits to a brand new bicycle (warranty, confidence that everything works correctly), there is quite a large market of quality, used bikes that will be gently used, come with higher end components, and be manufactured with lighter, quality materials. For similar cost of a new bike having entry level components (ala Tourney), one can reasonably expect to find available an aluminum frame hardtail with mid-level components (ala Alivo). Perhaps the used market could provide what you seek. – Jeff Aug 29 '20 at 18:09
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Is it not literally suggesting cross-chaining?

Cross-chaining is putting a chain at extreme angle between front and rear cogs. The picture above illustrates correct ways to use the front triple. Incorrect ways would be: the biggest front ring with the biggest rear one, and the smallest front one with the smallest rear one.

I'm also thinking about removing two of the chainrings since only one chainring makes more sense.

I've seen/used the Tourney group and agree that the ratio range it provides is unnecessarily big for flat road applications. However, removing all but one front chainring, in my opinion, will leave you with a very narrow range at the back. Most people will be comfortable with existing two front chainrings of the Tourney setup (the smallest and the middle one), as the biggest front cog only makes sense for quite steep descents and high speeds, unusual for leisure cycling (or at least for non-mountainous terrain).

Note that chainrings on Tourney are riveted not screwed to the spider, so removing them will require some drilling or smashing. Putting them back on will become problematic as well. That is why I do not recommend it.

Say, I make it a 1x setup after removing two chainrings, (keeping just the middle one), will I still meet with cross chaining?

Strictly speaking, yes. The 7-speed chains were not designed to bend through the whole range of the rear cassette. Having a middle front cog with either the biggest or the smallest rear cog will constitute cross-chaining, albeit less grave. It will most likely work, just that it will not be in the intended use/range of the setup, and might lead to decrease in chain/drivetrain life, decrease in shifting reliability, may produce additional noise etc.

On top of that, you may start experiencing chain drops if you remove the front derailleur cage, serving as a chain catcher. True 1× setups have additional measures to increase chain retention, which Tourney does not provide. Again, in the Tourney case, the gearing range will just be very limited.

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Cross-chaining is a mythical beast. Yes, it's best to avoid riding significant distances with the chain at a wide angle, but you pretty much can't shift a bike without doing it occasionally, and there are advantages to being able to quickly access the full range of rear cluster gear ratios, without having to constantly fiddle with the front. Plus, it may be that the "perfect" gear ratio for a given situation may be one that provokes this dreaded beast.

Note that cross-chaining wasn't really a "thing" with old 2x5 setups, and only gained note when the rear cog count surpassed 8. Plus, with a single front you can't use the full range of gearing without crossing the chain.

Finally, note that the diagram in question isn't even suggesting cross-chaining.

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In general you want to avoid extreme chain angles.

This gear calculator has a typical 3x7 setup with 50/40/30 crank and 14-28 7 speed Shimano freewheel

https://gear-calculator.com/?GR=DERS&KB=30,40,50&RZ=24,22,20,18,16,28,14&UF=2215&TF=90&SL=1.5&UN=KMH&DV=teeth

The max chain angle is set to the smallest possible .

It shows that 50/28 30/14 and 40/14 and 40/28 are all cross chained.

In general the chain wants to be straight which is achieved by using middle gears in the middle chainring, small gears in the top and large gears in the small chainring .

1x setups can be considered to leave the smallest and largest gears cross chained because there is only one chainring position.

Possibly with modern 1x setups this isn't a problem, but with a cheap 3x crankset, removing chainrings won't help anything.

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