Mechanism to move the chain from one sprocket to another.

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5
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2answers
4k 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
2answers
33k 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 ...
3
votes
2answers
5k views

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 ...
28
votes
5answers
6k 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 ...
6
votes
2answers
15k 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 ...
5
votes
3answers
837 views

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
votes
3answers
3k views

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 ...
3
votes
3answers
313 views

What are the most common causes for hysteresis in the rear derailler?

I have often seen derailleurs on cheap MTBs to degrade in performance by showing hysteresis. By that I mean that to switch to a certain cog, one needs to shift one cog further and then immediately one ...
2
votes
1answer
1k views

Replaced Shimano Bottom Bracket, now front derailleur won't shift to largest gear

OK, so in my quest to get my old Trek 7000 ZX MTB running again after a long retirement, I am having an issue with replacing the bottom bracket. The bike came with a Shimano LP25 that is marked BC ...
16
votes
1answer
968 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 ...
22
votes
4answers
29k 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 ...
26
votes
7answers
6k 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?
8
votes
1answer
6k 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 ...
7
votes
3answers
9k 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 ...
3
votes
1answer
615 views

How do I properly adjust a front derailleur?

I have a Shimano FD-TX50. How should I adjust it?
3
votes
3answers
282 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 ...
2
votes
3answers
2k views

Front derailleur doesn't seem to be moving

I'm trying to troubleshoot my 24 speed hybrid bike. As it was, the front shifter was having very little effect. I would change gears and not much would happen. When I had a chance to look at it, I ...
4
votes
1answer
4k 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
10k 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 ...
3
votes
1answer
1k views

9 Speed Road STI + MTB Derailleur

Apologies if this is is obvious or has been answered before. I'm looking at setting up a touring bike, using road STI levers (Shimano or equivalent, looking at Tiagra 3x9 or possibly the Microshift ...
3
votes
1answer
936 views

How can I adjust index shifter so it doesn't skip the second chainring?

I recently replaced my chain and cassette on my commuter bike. It was a first time operation for me, as I am a new to doing bike maintenance. That part seems to have gone fine. While I was at it, I ...
3
votes
3answers
1k 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 ...
2
votes
1answer
3k views

Which derailleur should I use with a Shimano 7 speed freewheel 14-34T megarange?

Which derailleur should I use with a Shimano 7 speed freewheel 14-34T megarange in order to prevent the derailleur from rubbing the cassette in 2nd.
1
vote
3answers
4k views

Front derailleur won't spring back to lower gears

The front derailleur on my mountainbike sometimes gets stuck in high gears. When this happens and I want to shift down I can nudge it a bit with my foot and it will spring back to the lower gear. I ...
1
vote
1answer
2k views

How to setup triple front derailleur with a double crankset

I want to use my front derailleur which is a tiagra on a 3x10 speed setup with a compact double crankset making it a 2x10 setup. What is the proper procedure for setting up the triple chainring ...