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

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34
votes
5answers
57k 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 ...
31
votes
4answers
9k 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 ...
30
votes
5answers
9k 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 ...
26
votes
2answers
7k 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?
23
votes
11answers
8k 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
3k 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
4answers
997 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 ...
14
votes
2answers
16k 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).. ...
11
votes
3answers
3k 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. ...
11
votes
2answers
5k 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 ...
10
votes
7answers
4k 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 ...
10
votes
3answers
2k 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 ...
10
votes
6answers
13k 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 ...
10
votes
10answers
26k 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
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
4answers
621 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
283 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
521 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
3answers
655 views

Do aluminium chainrings/cassettes contribute to chain wear?

In trying to achieve a long lasting, low maintenance drivetrain, I've read statements about aluminium oxide being the source of the black colour of chain dirt and also being highly abrasive: ...
7
votes
4answers
15k 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
351 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 ...
6
votes
4answers
8k 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
1k 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
3answers
14k 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 ...
6
votes
2answers
432 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
1k 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
3answers
233 views

Derailleur Pulley Wheel Compatibility

I can't find replacement pulley wheels for my derailer that are explicitly made for it. Should I be safe replacing them with a set with the same number of teeth (i.e., the same diameter) and targeted ...
5
votes
1answer
212 views

belt vs chain for what matters performance only

Let's set apart all pros/cons of chains vs belts, like: ease of maintenance, need of a custom frame, cost, spare part availability, all of that: nope. This question is very focusing only on ...
5
votes
2answers
301 views

What does “chain binding” mean?

I'm reading on chain tensioning, the generic idea is that if the chain is too loose it will fall off, if it's too tight it will "bind". I'm having an hard time understanding what "bind" means in this ...
5
votes
2answers
309 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 ...
5
votes
2answers
1k 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 ...
4
votes
6answers
2k 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 ...
4
votes
4answers
9k 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
3answers
2k 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. ...
4
votes
4answers
144 views

Does (square-taper) BB spindle length affect Q factor?

I am having knee and ankle trouble on my commuting bike (1993 Specialized mtb) and this has a 73mm BB with a spindle length I haven't measured but there is space between crankarm and frame. I wanted ...
4
votes
2answers
381 views

Is it possible to install a 1x11 drivetrain on an old MTB?

I have an old Stumpjumper from 1984. It has the original 3x5 drivetrain with friction shifting. I'm intrigued by the idea of converting to a 1x11 drivetrain, but I don't know what factors to consider ...
4
votes
1answer
201 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
2answers
5k 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
21k 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
4answers
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 ...
4
votes
3answers
766 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 ...
4
votes
2answers
1k 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
514 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
241 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
1answer
835 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
830 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
1answer
81 views

Converting a 7/8spd cassette to 4/5spd

Lets get some things ticked off: Friction shifting, check Narrow stance cranks, check 2 or 3 spacers on the right hand side, check Single chainring, check (That's the context.) Are there ...