Mechanism to move the chain from one sprocket to another.
25
votes
5answers
2k views
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 ...
22
votes
6answers
3k views
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, a part from being heavier, how much will I loose in performance if I use hub gear?
16
votes
5answers
1k views
Is there such thing as an automatic transmission for bikes?
Has anyone ever designed or manufactured and automatic transmission (automatic shifter?) for cycling?
I imagine such a device would automatically change the gearing to allow the rider to maintain ...
15
votes
1answer
645 views
Relative efficiency of different commute bike setups
My interest is in long distance commuting (e.g. more than 50 km a day) and the relative efficiencies of different commute bike setups (e.g. drop bars vs flat bars, fenders vs no fenders, panniers vs ...
14
votes
4answers
12k views
What are the pros and cons of internal gears?
I've had my hybrid 24-speed for a bit over 3 years now, and just last weekend, when looking for a bike for my wife, discovered internal gears. Suffice to say it blew my mind when I saw 7-speed ...
11
votes
4answers
3k views
Why has indexed shifting displaced traditional friction shifting?
I really don't like indexed shifters, at least on the front. They're harder to adjust, more sensitive to cable stretching, and limit the number of gear combinations you can use (because you can't ...
10
votes
2answers
589 views
How do I locate and loosen the rear derailleur hanger bolt?
Context:
I need to remove my rear derailleur so that I can attach an alignment tool and straighten things out.
Images of the rear derailleur while the bike is upside-down:
...
10
votes
4answers
8k views
How do I prevent the rear derailleur from slipping gears?
What's the best way to tune the rear derailleur of my bike to stop slipping gears? It seems that every time I re-adjust it, the middle/upper gears are perfectly aligned, but the lower gears never ...
9
votes
1answer
224 views
Setting light to a derailleur
At 3:30ish in this video, they set light to a front derailleur. Why? Degreasing it? Waxy lube that needs melting in? I can't think of a good reason. Any ideas?
8
votes
3answers
678 views
How tight should my chain be?
I recently put new tires on my bike, and in so doing, removed and replaced the wheels. It seems that now my chain has more slack in it than before, and if I pedal backwards while in the smaller cog ...
8
votes
1answer
1k views
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 ...
7
votes
3answers
1k views
Why does my rear derailleur keep breaking?
I upgraded my rear-mech with a new cassette, chain and new cables a few weeks ago since then i've mangled two rear mechs!
Both times I've just been riding along; not in a big gear; not at the ...
7
votes
4answers
459 views
Why do current, entry-level shimano rear derailers have large-diameter pulleys?
I have seen (and recently bought) entry-level rear derailers from Shimano (Tourney for MTB, 2300 for road bike), and I keep wondering why they are making these parts with such large pulleys.
I don't ...
7
votes
1answer
350 views
Chart for bicycle component quality?
I'm not very familiar with all the different component groups available and wondered if there's a chart that ranks their quality (or price).
So I'd know that Shimano 105 is the same level as SRAM ...
6
votes
3answers
888 views
Single speed conversion chain keeps derailing rear cog under load?
The chain on my SS mt bike keeps coming off the rear cog under load (like when I hit a steep hill) it will hold right after it's tightened but after a few hills it starts coming off non-stop. Talked ...
6
votes
3answers
294 views
Apart from the size, is there any difference between chains for derailleurs or for single-speed / internally geared hubs?
I might need to replace my bicycle chain (see this question). The store where I've bought components before (cyclecomponents.com) seems to be entirely marketed to derailleurs, and I have an internally ...
6
votes
4answers
293 views
Comparing gear ratios on different bike types
How can I compare gear ratios on different wheel sizes? How can I compare gear ratios on MTB with tracking bikes with bigger wheels? How can I compare gear ratios with gear hubs?
6
votes
1answer
6k views
When to change derailleur pulleys?
A friend said me that if you have one part in a very bad condition like a cassette and then you put a new stuff like a new chain it will destroy the new stuff very quickly. A LBS said that I should ...
6
votes
1answer
3k views
Chain slipping off derailleur jockey (need suggestions ASAP)
Last week, I had to abandon a training ride due to my chain slipping off my rear derailleur jockey. This would only happen when shifting, and most often when either shifting chainrings or shifting ...
5
votes
2answers
553 views
Upgrade Shimano from 9- to 10- speed
I'm thinking of upgrading 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. ...
5
votes
3answers
3k views
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 ...
5
votes
3answers
814 views
Why does my bike stick in low gears?
When I change into a low gear (i.e. onto a bigger cog) on my back cog all is fine. However, when I later change up again the chain sticks on the larger cog. I commute about 10 miles a day and this has ...
5
votes
2answers
609 views
is this derailleur short cage or long cage?
I'm selling the rear derailleur off this bike, and someone asked whether it's short or long cage. I assume it's long. Is this correct?
5
votes
4answers
11k views
Can a rear derailleur be used for either a 9 speed cassette or 10 speed cassette?
I currently have a 9 speed 11-25T cassette on my road bike. I'm thinking about switching to a different cassette with more teeth on the climbing gear. The cassette I'm currently look at is a Shimano ...
5
votes
3answers
144 views
How can I increase the highest gear ratio?
I am looking for some higher cog front gears for an old bike I am considering. I've been away from it for some time and don't know the current number of cogs on the front ring, but I am looking to ...
5
votes
3answers
4k views
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 ...
5
votes
1answer
539 views
Putting a front Derailleur on a carbon frame
Do you put anything under the clamp on the carbon to protect it? In the past I've tightened brakes on MTB handle bars to much and wrecked them so I'm wondering.
4
votes
7answers
2k views
4
votes
2answers
210 views
Different Gear Type when there's no Front Derailleur?
I have a 7 speed Jamis Boss Cruiser, 7 gears in back and one up front. I've been using it fine for several months now. Lately, the chain is coming off of the single front gear, usually after stopping ...
4
votes
4answers
371 views
What can I do to keep my rear derailler in good condition when commuting in the snow?
In the winter, it seems that whatever I do, my rear derailleur stops functioning after few weeks of commuting in light snow. Ice always gets in there somehow, and the chain refuses to move the wheel, ...
4
votes
3answers
1k views
Replacing the front derailleur: unlink the chain?
If I want to replace the front derailleur on an already set up bicycle (replace SRAM Apex with SRAM Force), do I have to unlink and relink the chain on order to thread it through the FD cage? Or can I ...
4
votes
2answers
7k views
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 ...
4
votes
3answers
906 views
Why is there a distinction between friction and indexed derailleurs?
I've seen people make a distinction between a derailleur being for friction or indexed.
Is this distinction somehow functional? I can't see how it could be, because every derailleur I've ever seen ...
4
votes
2answers
455 views
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 ...
4
votes
3answers
500 views
Where are my barrel adjusters for my shifting cables?
I have a Devinci Caribou I and I was trying to adjust the front derailleur. I got the top and bottom stops adjusted right, but it seems that it doesn't downshift correctly from the biggest cog to the ...
4
votes
6answers
10k views
Problem with chain skipping without trying to shift (even with new chain and gears)
I have a mountain bike where the chain intermittently skips when put under load on the middle (and very rarely on the smallest) chain ring. It is not related to shifting.
I've taken several steps to ...
4
votes
1answer
385 views
Upgrade Shimano Sora shifters to 105
I want to upgrade my 3x9 Sora shifters to 3x10 105s. However, looking at the Shimano Compatibility Chart, it appears to indicate that I'll have to replace my front and rear derailleurs in addition to ...
4
votes
3answers
4k views
Can I fit a cassette with a larger range with my Shimano Tiagra 10-speed ( GS-4600) derailleur?
I'm currently running a 2x10 shimano tiagra 10-speed drivetrain with a 50/34 compact crankset, a 12-30 rear cassette, and a Shimano Tiagra GS-4600 derailleur (that's medium cage aka road long cage) on ...
4
votes
1answer
83 views
Are there mechanical advantages and disadvantages of various front derailleur styles?
In general there are:
High clamp
Low clamp
Braze on
Top pull
Bottom pull
And in particular, is any of those better choice regarding reliability and durability for touring bicycle.
4
votes
1answer
234 views
Should replacing the rear derailleur on my 80s road bike with a Campy Nuovo improve shifting?
I'm considering replacing the Simplex SX410 derailleur for a Campy Nuovo Record on my early 80s Mercier (6-speed cassette). Reason being that there has been for several years now a problem shifting ...
4
votes
2answers
394 views
Practical benefits of expensive jockey wheels?
Today I had to make a detour to the bike shop as a jockey wheel decided to fly out of a friend's derailleur. The shop were able to supply a replacement retaining bolt free of charge, however the only ...
4
votes
2answers
477 views
Converting crankset from 28-38-48 to 30-39-53
My current front setup is a 28-38-48 crank with Deore XT shifter & derailer. In addition to a FD-443 and top/bottom-pull converter, what else will need to be purchased for proper shifting?
Also, ...
3
votes
1answer
348 views
3
votes
3answers
450 views
Front derailleur sticking, not shifting. Will soaking in solvent damage parts?
I've got an older deore lx front derailleur for a mountain triple crankset. It wasn't shifting properly, and it seems that it's sticking and not returning back to a neutral position when I shift it. ...
3
votes
1answer
699 views
Is it practical to replace two sprockets on a cassette?
My bike has 53/39T chainrings and a cassette with 12,13,14,15,17,19,21,23,25 sprockets, but I like to ride up steep mountain roads. Is it possible (without great expense) to replace two sprockets to ...
3
votes
1answer
208 views
Which pulley is which on my Shimano STX RC derailleur?
I disassembled my rear derailleur to clean it; when I removed the sprockets they basically looked the same; both jet black and caked with all sorts of black grease-like-stuff. I figured they were the ...
3
votes
3answers
533 views
What causes my chain to derail at the rear when I accelerate?
I recently bought a beat-up old mountain bike for commuting. I've tried to clean and adjust the derailleurs and everything seems to work well enough in my garage. But when I put heavy weight on the ...
3
votes
3answers
225 views
Gear shift adjustments
I recently had to replace the shifters on my bike. The replacement was easy enough, but now when I shift the derailleur either jumps too far or too short. I've tried using the adjustment screws on the ...
3
votes
1answer
194 views
Why is my front Derailleur not shifting as smooth as it used to?
I have a Specialized Hard Tail 10' Model. When I ride and am shifting to the bigger gear on my front derailleur it isn't as smooth as it used to be or sometimes doesn't shift to the gear I'm going ...
3
votes
2answers
11k views
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 ...
