66

Modern chains have inner and outer links. On a conventional chainring, all of the teeth are the same width, and therefore have to be narrow enough to fit into the chain's inner links. This means that there's enough space for the chain to move about a bit from side to side on the chainring, which can cause it to fall off. Historically this hasn't been much ...


26

In most cases with bicycle parts, more expensive means lighter. There can be exceptions, especially when you get to the super low end parts where cheaper can also mean cheaper construction. Since you put so many miles on your bike and it seems important to you, I would spend the extra 2 pounds and grab the Acera. XT is generally used on mountain bikes where ...


19

In my experience - breakage is not directly correlated to wear. I've had bikes with unknown mileage on them, and have chosen to ride the transmission into the ground. Generally the performance slowly deteriorates, with chain slip under power being a sign that things are getting bad. Unlike other answerers, I've never had a worn transmission break and strand ...


18

You have a zero cost solution, which is to keep the front derailleur but remove the cable (and shifter if you like). Then use the FD limit screws to fix it in the right position to act as a chain guide. You don't need a 1x chainring, in fact using one with a 7 speed chain is probably less than ideal, so you're actually better off sticking with an existing ...


15

UCI time trials are a class race contested in the tiny fractions of a percent, tiny differences in equipment become very important. Riders practice in wind tunnels to tweak everything from clothing to pedalling style, because a shift that gives an overall gain of 0.01% in speed can result in a win. Considering more than just the top gear, the jump from 50/...


15

Chainrings designed for multispeed systems have special pins and ramps in them, to assist shifting. Key word being assist. If you have rings for a certain config, it might not have those features in the right spots. If you don't have them, shifting won't be as good as it would be otherwise. That doesn't necessarily mean it'll be complete garbage either, ...


14

This is actually a matter of the force multiplication that each chainring provides, and the size/mass of each chainring. Force difference Let's propose, only for a moment that you had a chainring as big that the radius of it is almost the same as the crank length. If the rider stood to pedal while using that chainring (and using simple platform pedals). ...


14

You have a couple different options. I think the cheapest would be to switch to a compact crankset which would change the front chainrings from 52-39 to 50-34. I'm pretty sure you could do this while still using the same shifter. Changing the front shifter is required if you want to go from a double to a triple, as is changing the front derailleur. If you ...


14

Switching from 3x8 to 1x11 would be an expensive upgrade, well beyond your budget unless you get lucky hunting for used equipment, and may require a cascade of upgrades you hadn't planned on, which increase the cost further. You'd probably be better off saving up for a new bike--bike manufacturers are able to get parts at much lower cost, so when you buy a ...


14

Gear ratio range. If you decrease the chainring sizes you decrease the highest ratios available. It's not possible to make the gap between the chainrings much bigger and get decent front shifting so the large ring has to shrink with the small one. It's easier for manufacturers to make a wide ratio cassette that retains an 11 tooth sprocket and shifts ...


14

Despite the "hell will freeze over" warnings (it doesn't) it is worth considering why you ride a bike, and why you ride an 11- or 12-speed bike when a 9 speed will do the job just fine before going too deeply into the cost vs performance tradeoffs of when to change the chain. You are clearly aware the that shifting performance will deteriorate once ...


13

Yes. The cassette teeth are clearly worn, and the large chainring teeth have worn into characteristic shark fin shape. If you use new chain with these, it will skip. The small chainring looks still good.


13

The specific model of rear derailleur you have is an Acera RD-M360 SGS, produced about 2009-2011, for 7 or 8 speed drivetrains. Shimano very helpfully provides archive specifications on the product info page. Looking in the 2009 spec PDF we can see that the max size of the largest sprocket the derailleur will handle is 34. I believe 12-34 freewheels do exist,...


13

Yes - after that mileage you will need both a new chain and new cassette. A new chain on the old cassette will not mesh right, and accelerate wear on the new chain. Depending how much chain elongation has accrued, you may need new chainrings too. They wear slower because more teeth are engaged in the chain. Look at the chainring and see if the scallops are ...


13

Additionally, a 1x chainring is likely to be "narrow-wide" to help with chain retention. If you look closely, every tooth is alternately wider and narrower, so you place the chain on such that outside plates are around a wide tooth. If you had used a FD to change chainrings, there's a 50% chance the chain will land wrong, and your wide tooth gets ...


12

Shows some wear, but looks OK. All teeth look symmetrical and so do the spaces between them. Really worn teeth look like a swept back shark dorsal fin or develop a visible burr. Do a Google image search for 'worn chainring teeth' and you'll get plenty of examples.


12

You mostly answered your own question: the racing market drives the industry, sometimes to the detriment of the availability of real-world gearing. A major compounding factor is that there are a lot of hoops a person has to jump through to get smaller rings on their road bike, starting with buying new, weird, mostly old or retro cranks. Making things work ...


12

There is a limit to the amount of tension a given chain should be put under. Smaller chainrings increase that force - the pedal arm and chainring form a lever, and the smaller the chainring (and longer the pedal arm) the more force will be applied to the chain given a fixed force on the pedal. What you might be gaining in terms of chainring and cassette ...


12

In the ideal case, the chain will not actually be rubbing significantly against the chainrings under load. As the chain wears, the spacing between the chain links becomes different from the tooth spacing, and this difference in spacing means that there is sliding contact as the teeth engage the chain. The rollers inside the chain help to convert some of this ...


12

From looking up the specs I presume your crank is FC-M8000-2. If you're saying that the crank arms are moving while the big ring and chain remain stationary in space, and the rear cog didn't move, the only possible explanations are that either the interface between the spider and the right crank has failed, or the metal toothy part of the composite XT big ...


10

Interesting question. Real world conditions are messy with multiple factors impacting any analysis, as such my answer will be speculative, but based on a number of sensible working assumptions. Chainring degradation as a source First lets consider how much material comes off a chainring. Generally speaking, if you replace your chain regularly before it ...


10

Sorry, those chainrings are riveted in place. You just have to replace the whole crank arm.


10

The combination of rings and sprockets you can use depends on the specs of the derailleurs, specifically the total capacity of both the front and rear derailleurs and the max sprocket size of the rear derailleur. Front total capacity is just the max difference in size of the small and large chainrings, measured in teeth. Rear total capacity is the max (...


10

If the chainrings are in good order, I would recommend servicing the front derailleur and continue to run it as 3x. The reason is that front dérailleurs rust quickly but are often chrome plated and it’s actually easy to remove the rust. If the derailleur is temperamental it is typically solved by replacing the shifter inner cable ($1 on eBay) and ...


10

Disclaimer: I am not a fan of upgrading bike components. I believe for most people, it's a waste of money, usually trying to make a silk purse from a sows ear. Some succeed, but few do better than using the money to upgrade the entire bike. (Replacing worn out components with better ones can be worth while if done carefully.) With just two years riding and ...


9

Yes, this should be possible. Though there are several things you need to check to ensure it is compatible: Number of bolts, and bolt circle diameter (BCD). Count the number of bolts, and measure the distance between the centre of two bolts. Then check Sheldon Brown's Bolt Circle Diameter Crib Sheet to see what the BCD is. Common sizes are 110 (mountain ...


9

I expect that after 10,000 km your chainring also needs to be replaced (frankly, I find it astonishing that you made it that far without replacing anything else. That's amazing.). Am I correct in guessing that you spend most of your time in your middle chainring? If so, it will be significantly more worn than your large or small rings, which would explain ...


9

Here are some points taken from the literature: Mechanical efficiency is usually 88-98% for majority of deraileur systems (when clean,lubricated and new) Drivetrain efficiency decreases with smaller rear cogs, Highest efficiency can be reached at high torques and low cadence, Chainline effects are negligible, imposible to note with measurement apparatus, ...


9

You should not have to replace the entire crank-set. In general, a 'mid-compact' 52/36 crank will have a 110mm BCD spider, which allows 50 and 34 tooth rings to be installed. The Ultegra FC-R8000 crank on the Canyon comes in 53-39, 52-36 and 50-34 versions, so you will be able to get the smaller rings for that specific crank. The front derailleur may need ...


9

4mm at the closest point is about the safe spot. 3mm is about the sane bare minimum you can go to if you want to push things. Less is asking for trouble. Note that frames, cranks, rings, and spindles do vary in how flexy they are and riders vary in habits and strength, so one can only approximate here. If you stacked the movement from a bunch of flexy things ...


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