Questions about a bicycle's drivetrain system, including the chain, gears, chainring, derailers, etcetera.

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31
votes
5answers
45k 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 ...
30
votes
4answers
7k views

Why do bikes have their drivetrains on the right?

Every bicycle I have seen in my life has its gears and chain on the right side? Why is this? The only thing I could find regarding this question is this forum topic, which speculates about things such ...
29
votes
5answers
8k 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 ...
24
votes
2answers
6k views

Why does pedalling backwards not move my bike backwards?

On the BMX bike I have, pedaling backwards moves the chain but doesn't drive the wheels of the bike backwards like you would expect it to. Why is this?
21
votes
9answers
7k views

Is there such thing as an automatic transmission for bikes?

Has anyone ever designed or manufactured an automatic transmission (or automatic shifter?) for cycling? I imagine such a device would automatically change the gearing to allow the rider to maintain ...
16
votes
2answers
2k views

Is there a practical gain from elliptical/oval chainrings?

I have seen competitive (amateur) cyclists with oval chainrings (front). What is the deal? Are they just for showing off, or is there a practical gain from it (different force transfer).
15
votes
3answers
1k views

How bad is cross chaining?

Accepted wisdom is that cross chaining is bad and that we should never do it. However, most of us set up our bikes so that we can run any gear combination. Invariably, I'll occasionally look down ...
14
votes
2answers
13k views

I'm changing from 8-speed to 10-speed will I need to replace my rear Hub?

I've dug an old road bike out of the garage for the winter and need to upgrade the drive-train, I'm happy about most of what I need but but I'm not sure about the rear hub (an old Shimano Ultegra).. ...
12
votes
4answers
848 views

Minimal effort chain cleaning

One of the main reasons I eventually give up my bicycle commute in winter is that keeping my bike -mainly the drivetrain- clean despite all the rain/dirt/salt/hail/snow becomes too much of a time ...
11
votes
3answers
2k views

How to avoid wearing out gears?

I have a Specialized Tricross which I bought new last year. In that time (approximately 1K miles), I wore out my chain and gears. At least two of my gears are still slipping, even with a new chain. ...
9
votes
10answers
17k views

While pedaling standing up, bike crank gives in as if shifting, what is causing this?

While standing up and pedaling, the cranks give in as if shifting. It seams like I am shifting down, but my hands are off the shifter, almost like the chain is skipping a link. I took it to a bike ...
9
votes
6answers
11k views

Mysterious case: chain falling off large chainring, how to fix?

On my commuter bike I decided to rid myself of the small inner chain ring (which is almost never used) and front dérailleur (now redundant). However, I have come across an unusual problem. Whilst ...
9
votes
2answers
2k views

Any experience with shaft driven bikes?

I've ridden a shaft driven bike once, when biking in deserted mines in Limburg.‡ They used shaft driven bikes because the mines are damp, and a shaft can be enclosed completely, protecting it ...
9
votes
1answer
3k 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 ...
8
votes
3answers
1k views

What's the point of removing the excess oil after lubing the chain?

There is a very strong point in bike-mechanics culture, which I've seen in very competent answers here, too, to apply one drop of lube in every single roller of a clean chain, and then (!very ...
8
votes
4answers
566 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, ...
8
votes
1answer
269 views

How far off a chain line can I go?

I'm struggling to find a replace crank set to replace the SR Suntour set that came on my bike. The chain rings were riveted together so on bending one I had to replace the set. There's very few 7 ...
7
votes
4answers
368 views

What's the point in a freewheel/cassette with incrementally sized rings?

Pictured is a freewheel with 15, 16, 17, 18, 19, and 20 tooth sprockets. What I don't understand is why such small increments are worthwhile. Surely the point of having gears is the variance that they ...
7
votes
4answers
12k 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 ...
7
votes
2answers
339 views

Have there been designs of bikes with stepless transmission?

Today we studied about mechanical stepless drives, which appear to be used quite widely in industry machines, such as CNC lathes. The concept of varying the transmission ratio arbitrary, without ...
7
votes
5answers
3k views

Does gear ratio affect Power?

Let me preface by saying that this may not be the right SE. I considered asking on the Physics SE, but I thought I might try here first. If it is wrong, I am not against it being migrated. From basic ...
6
votes
4answers
6k views

How much distance can I put on drivetrain components?

I figure the jockey wheels on my derailer will last nearly forever, but what about the rest: cassette, chainrings, and chain? How many miles, kilometers, or furlongs do they normally last? I know ...
6
votes
3answers
857 views

Is it possible to use road-style brifters with an internal gear hub?

I have a touring bike with road-style Shimano brifters, which I love. I'm also very intrigued by internal-gear hubs, but these hubs seem to focus on rotary or push-button shifters. Is it possible to ...
6
votes
2answers
396 views

At what point does one need to replace a chain ring on a mountain bike?

The large chainring on my mountain bike is missing a number of teeth on one side (apparently the side I like to go over rocks on). Is it harmful to the drivetrain to ride without these if I'm not ...
5
votes
3answers
959 views

Has a bike been made with a rear derailleur above the chainstays?

The question title pretty much sums it up, but has a bike with an alternate drivetrain style like this been made? This would mean a derailleur mounted essentially upside down with the tension pushing ...
5
votes
2answers
260 views

What parts do I need to upgrade my drivetrain?

I have a Cannondale M300 with a 7-speed drivetrain. The parts are fairly worn and I am considering converting to a 9-speed as 7-speed components are getting harder to find. What parts do I need to ...
4
votes
4answers
7k views

Why are there almost no bikes with a single chainring?

Bikes with two or three chainrings are the norm, and then there are singlespeeds, but except for kids' bikes, you see almost no stock bikes with a single chainring in front but a cassette and ...
4
votes
1answer
178 views

What is the name of the part by the right-hand pedal on to which the chain grips?

There's a part common to all bikes that resides by the right-hand pedal that holds the front sprockets upon which the chain grips? I'm aware that this part contains the sprocket or sprockets on to ...
4
votes
3answers
11k views

Can I replace chainrings without replacing the rest of the drive train?

I now ride a 60cm SurlyLHT with chain rings at 26/36/48t. Can I replace with a smaller set at 22/32/46t (or similar combination) without having to replace the entire drive train - cassette, rear ...
4
votes
2answers
4k views

What's a good, reliable mountain bike drivetrain (1x10?)

I'm thinking about switching my Salsa El Mariachi 29er mountain bike from singlespeed to gears. I love the reliability and simplicity of the singlespeed, but I've been doing more rides that involve ...
4
votes
5answers
1k views

Transmission (cassette/crankset) considerations for 1st road bike purchase

I currently have a touring bike, with fenders, rack, panniers, and so on. I currently run a triple crankset 28/38/48 and 9sp 11-34 cassette. I mostly commute and tour with this bike. And with a fair ...
4
votes
3answers
17k 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
2answers
785 views

Weed-eater bike conversion - Safe rpm?

I've recently started working on retrofitting an old bike with an even older weed-eater engine. The engine will sit atop a bicycle rack and directly drive the rear wheel tire (engine has a built-in ...
4
votes
3answers
2k views

How to: Sram 2x10 to 1x10

I'm thinking on converting my Sram transmission 2x10 to 1x10, this is with a single chain ring. My biggest doubt is how to prevent cross chaining, do I need to get a special chain or how do I prevent ...
4
votes
2answers
455 views

Chain drops in smallest gear under load

I'm baffled. I installed a new chain, cassette, cables and housing yesterday. On the stand, all is happy and shifting is silky smooth. On the road all seems happy except on the bigger cogs in back (in ...
4
votes
1answer
217 views

Claud Butler Tandem - add a front derailleur?

I'm in the process of stripping a SWB Claud Butler tandem so I can get it repainted. There are a couple of things I need help with.... a) Can you fit a front mech to the bike, and if so, are there ...
3
votes
5answers
1k views

Are older road bike parts compatible with newer standards? How do older and newer bikes match up performance wise?

I'm a big mountain biker and looking to get into road biking. However, I don't want to drop $1,500 on a new or relatively new road bike without being sure I'd want to stick with it. Anyway, I found ...
3
votes
3answers
1k 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
679 views

Should I remove the chain before installing new rear derailleur?

I want to put a new Sram X7 instead of killed one, should I open the chain (if I have no chain lock) or it's better to open the derailleur?
3
votes
2answers
747 views

Is there a Campagnolo / Shimano compatibility issue for friction shift systems?

I know that for indexed systems, mixing campy and shimano parts is a no-no. Does the same hold for friction drive trains? The reason I ask is that I've never worked on campy parts before and I'm ...
3
votes
3answers
678 views

Thread locking fluid on fixed cog

I just recently got a single speed with a flipflop hub and got the bike shop to switch it to the fixed cog. While riding around, the gear came loose on the back hub and almost flung me off so I had ...
3
votes
1answer
300 views

Should I have a spare cassette or a spare wheel?

I have a road bike that I use for triathlons as well as club rides in the evenings and on weekends. I don't have the bike in front of me, but the range of the cassette is on the low side. I'm more ...
3
votes
3answers
2k views

Why is my chain riding up and skipping teeth on the freewheel?

Due to a number of reasons, I would like to keep my freewheel at all costs (It's a Sachs freewheel, the bike has all sorts of more 'vintage' components, and they're hard to come by). From reading all ...
3
votes
2answers
1k views

campagnolo wheel on shimano or sram drivetrain?

I have a road wheel that has Campagnolo splined hub and 10 speed cassette. I'd like to know if anyone has any experience running a Campy wheel on Shimano/Sram drive train? I know the measurements of ...
3
votes
3answers
454 views

Chain falling off inner chain ring no matter how L screw is set

Bike is a relatively new Cannondale Carbon Synapse with the Ultegra 6800 groupset (although front chainrings are FSA). Has about 1000KMs on it. Bike has been great, but I went out on a ride today ...
3
votes
1answer
830 views

Can a 10-speed chain be used with a 9-speed cassette?

I have an extra 10-speed chain I would like to use with a 9-speed cassette on my mountain bike. Will this combination work ok?
3
votes
1answer
67 views

Indexed rear derailer shifts two cogs for each step

I'm trying to troubleshoot poor shifting issues on a mountain bike that appears to have been built out of the spare parts box… The current problem is "instability" on the rear derailer – the chain ...
3
votes
1answer
3k views

Can I run 2x10 XT Shifters on a flatbar road bike with 105 10 speed STI components?

I want to run 2x10 XT shifters on a flatbar but still want use the 10 speed 105 components of the road bike would there be any problems?
3
votes
2answers
838 views

(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 ...
3
votes
1answer
3k views

How to remove a Shimano Quick-Link?

I'm currently repurposing an old frame and replacing the drivetrain. If possible I'd keep the old 7 speed drive train the bike had together in case I ever find a use for it. The chain is an HG40 ...