Questions tagged [derailleur]
Mechanism to move the chain from one sprocket to another.
98
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How to calculate the capacity of a rear derailleur
It's easy to calculate what capacity of a rear derailleur will be needed based on the size of the big and small chainring and the big and small cog. What about the converse question, how to calculate ...
- 7,846
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2
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Moving from Shimano 9- to Shimano 10- speed
I'm thinking of changing the 9-speed Tiagra rear mech on one of my (road) bikes to something, still Shimano, but 10-speed.
The obvious replacements I'll need are cassette, right-shifter and chain. But ...
- 9,753
9
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3
answers
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Road Shifters, Mountain Rear Derailleur?
I have a road/cyclocross/commuter frame that is currently spec'd with road components - all Shimano 105, with an Ultegra rear derailleur.
The cassette (10 spd) tops out at 27 teeth, and the rear ...
- 1,478
11
votes
3
answers
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How do I adjust my rear derailleur (Shimano SIS) when it is only slightly out?
It has been a while since I had my bike serviced and the gears are sometimes slightly out of perfect alignment. This results in the occasional mis-shift. I also think the change in seasons have ...
- 6,273
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What's the efficiency of hub gears compared to derailleurs?
What's the efficiency of hub gears compared to derailleurs? I know that hub gears are not as efficient. Apart from being heavier, how much will I lose in performance if I use hub gears?
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3
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How can you identify if a Shimano rear derailleur is medium or long cage?
I have a 2013 Shimano XT rear derailleur. It is part of a 2x10 drivetrain. How can I find out if it is a medium or a long cage one? The picture below shows the derailleur.
- 4,352
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2
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Bike chain slips in a strange way
I bought a new bike about a month ago. And it made a strange sound from the first ride , I thought the sound was because it was new and will disappear with time but it didn't. The sound is like a ...
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Is my chain too long?
I'm in the process of setting up a new drive train. When using the smaller chainring and smallest sprocket (hence least amount of utilized chain), the chain brushes up against the bottom of the ...
user1480
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3
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Does a rear derailleur guard provide effective protection?
I recently caught my rear derailleur on a log and snapped it in two. I have done some recent work on some department store bikes and noticed that some come equipped with an axle mounted guard around ...
- 18.8k
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(Automatic Bike Project) amount of torque required to change gears?
I am planning to build an electronically controlled automatic bike transmission for my senior design project. I'm personally more of an electrical guy, so dealing with the mechanics is somewhat new to ...
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Determining which derailleur hanger is compatible with a frame
When your derailleur hanger needs replacing, is there a good resource for matching frames to hangers?
Mine was recently bent, so I had to dig through some websites and compare pictures of the hangers ...
- 7,846
38
votes
5
answers
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Perfectly setting up gears - how?
Every time I have my bike serviced, the bike shop sets up the gears on a stand in their workshop. The gears change perfectly on the stand, but when the bike is on the road, the rear derailleur doesn't ...
- 481
18
votes
2
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Chain slipping off derailleur jockey
Last week, I had to abandon a training ride due to my chain slipping off my rear derailleur jockey wheel. This would only happen when shifting, and most often when either shifting chainrings or ...
- 8,619
15
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6
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Bike is shifting on its own
Ever since I got my bike (Surly Long Haul Trucker), it has been prone to shifting on its own. This is almost guaranteed to happen when I stand up on the pedals, and happens regularly when sitting as ...
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Is there a downside to spoke protectors?
A few weeks ago, the derailer on my touring bike caught on the chain and ripped itself off the frame. (See the link below for more info on the incident.) The spoke protector was cracked in half by ...
