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15 votes
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What are these red devices on Shimano Nexave v-brakes and how do they work?

The red part's purpose is to limit braking power by flexing when the rider pulls brake level too hard. They are claimed to improve safety by preventing accidentally locking the wheel, but in practice ...
ojs's user avatar
  • 22.1k
14 votes
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LBS won't Service Shimano Dual Control Lever

I've successfully destroyed several right-hand levers by attempting to fix them once they've started acting up. One was a broken basket in the shifter, and I forget the actual failure in the others. ...
Criggie's user avatar
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11 votes
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What is this little plate found in the Ultegra groupset kit?

This part is called a backup plate and is used in conjunction with the front derailleur. The backup plate is mounted on the frame where the support bolt is located. Consult the Shimano installation ...
P. Barney's user avatar
  • 497
10 votes

Which Shimano Freehubs can I use on the WH-R550 wheel?

Shimano provides good official guidance about what the right part is and no guidance about what can be substituted. From the publically available exploded view diagram we know the matching part is Y-...
Nathan Knutson's user avatar
10 votes
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Hyperglide vs HG10/HG11/HG12

You seem to be asking about the freehub body dimensional standards as opposed to the features of the cassettes that go on each one per se, so I'll limit it to that. One of the confusing things is a ...
Nathan Knutson's user avatar
10 votes
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What is linkglide/cues and how do they differ from existing standards?

This answer is based on the documentation published here, from which the picture is taken. LinkGlide/CUES LinkGlide is technically a new tooth profile and sets the principles described below. There ...
Rеnаud's user avatar
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9 votes
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New chain coming off under torque

Put a fork in it - that chainring is cooked. https://www.sheldonbrown.com/chain-wear.html Your chainring has the classic "shark fin" tooth shape (note the slope of the teeth on the sprocket ...
Andrew Henle's user avatar
  • 10.6k
8 votes
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Hub spacer behind 105 cassette

These are used when the freehub body and cassette size are not matching, there are various combinations depending on the scenario 10-Speed cassette on 11-Speed freehub body requires both 1.85mm (...
DoNuT's user avatar
  • 4,481
8 votes

What is the role of the "safety plate" on a Shimano Hollowtech II crank?

It tries to prevent incorrect assembly. The axle has an indent to accommodate the pin of the safety plate. If you do not push the crank arm all the way onto the axle, the safety plate will not sit ...
g.kertesz's user avatar
  • 187
8 votes
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Replacing hydraulic brake lever

No one can say what you should do, just make a recommendation. Recommended option is to get a new olive and barb, do it right, do it once. If you have problems sourcing these in the time frame before ...
mattnz's user avatar
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8 votes
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Best derailleur compatible with 1.7 pull ratio?

Welcome to Bicycle Stack Exchange. Regarding your derailleur upgrade question. Prior to mountain bike 10 speed systems, all Shimano rear derailleurs, whether marketed for road or mountain bikes, had ...
Jeff's user avatar
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7 votes
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Is it normal for rear derailleur tension to impact front derailleur tension?

The cables are touching or entangled in the frame. This happens sometimes when re-routing a bare internal cable from scratch - it can be hard to avoid when shooting blind. The real error was letting ...
Nathan Knutson's user avatar
7 votes

Replacing pulley wheels on a RD-m3100 with non original parts. Can I use other Shimano pulley wheels?

There are two things that really matter when replacing pulleys on Shimano derailleurs with units not officially compatible: Tooth count Spacing, or in other words total thickness (the dimension that ...
Nathan Knutson's user avatar
7 votes

Both disc brakes stopped working after severe weather: No pressure when levers are pulled

Both front and rear brake fail in the same manner at the same day makes a coincidence unlikely imo. That being said, even harsh weather seems unlikely to alone causing this without some faulty install/...
WornChain's user avatar
  • 1,559
6 votes

Bent shift lever on Shimano Deore MTB shifter

I had exactly the same problem, bent it in a crash. I took it apart, used pliers, tried my own strength... nothing worked. Then I tried the metal pipe option mentioned here, and it worked like a charm....
Grant Davis's user avatar
6 votes
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Did this part come from my bicycle?

If you check this video: Youtube, "Installing a Bontrager Duotrap S Sensor on a Trek Domane": At 1:32, the guy who's installing the Duotrap holds a rubber ...
MagnusK's user avatar
  • 846
6 votes
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XTR 9100 left power meter on XT 8100 crankset

MaplePanda is correct, M8100 is incompatible with M9100. From the Stages website (emphasis added): SHIMANO HOLLOWTECH II MOUNTAIN BIKE For Shimano Hollowtech II mountain bike cranks, compatibility is ...
Ted Hohl's user avatar
  • 6,357
6 votes

LBS won't Service Shimano Dual Control Lever

The answer depends a little on the exact model and how deep you need to go. In general the problem is that replacement parts aren't available new if something is broken, and if nothing is broken then ...
Nathan Knutson's user avatar
6 votes

Are ST-5800 shifters compatible with hydraulic brakes?

As an alternative to the expense of upgrading to hydraulic STIs, there are cable-to-hydraulic adapters available. I recall seeing some Genesis road bikes equipped with them in a local bike shop. We ...
Greg Shailes's user avatar
6 votes

Hub spacer behind 105 cassette

If have an 11-speed groupset, and the largest sprocket is equal or larger than 34T, the cassette is in fact built using MTB specifications (MTB Hyperglide freehub bodies have kept the "historical&...
Rеnаud's user avatar
  • 20.6k
6 votes
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New V-brake arms don't spring back

Turns out it was the brakes themselves that were the issue. These were brand new, but after tons of playing around with them trying to get them to spring back and forth I broke one of the pins that ...
GeoK's user avatar
  • 101
6 votes

What is the role of the "safety plate" on a Shimano Hollowtech II crank?

The Park Tool site on step 3a for "Crank Removal and Installation: Two-Piece Compression Slotted" says: For Shimano® Hollowtech® II, inspect for a “stop plate” inside the left arm slot. Use ...
David D's user avatar
  • 21.5k
6 votes
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What is the role of the "safety plate" on a Shimano Hollowtech II crank?

Based on my observations from many Hollowtech II installs, I think it serves to retain the left crankarm (and thereby the whole crankset assembly) together if the two left crankarm bolts loosen (but ...
Ted Hohl's user avatar
  • 6,357
6 votes

Does a magic link or Powerlink require removal a regular chain link first?

The usual term in English is quick link. Powerlink may be a trademark. Nevertheless, that or magic link would be understood. With a quick link, you join two ends that are made from the inner links. ...
Weiwen Ng's user avatar
  • 32.5k
6 votes

Slight play in rear derailleur

Some play in this area, which is kept static under chain tension, is normal. Problem areas where play can develop would be in the parallelogram pivots, which would affect accuracy. That failure mode ...
Noise's user avatar
  • 14.1k
6 votes
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Wahoo Kickr cassette compatibility with Campagnolo

An S10 cassette will not shift well with a C10 drivetrain, and it would be unacceptable as a permanent solution if it were my bike. That said, the OP stated an intent to get a different bike. It's ...
Weiwen Ng's user avatar
  • 32.5k
6 votes

How to handle corrosion on brake pads screws on Shimano road bike disk brakes?

You can use the cotter pins from a pad like B05S to replace the screws completely. You may be able to drill out the snapped one and leave a hole that can take the pin. If you suspect the other one ...
Nathan Knutson's user avatar
5 votes
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Where does the weirdly shaped metal piece go inside of Shimano grip twist shifters?

On SRAM shifters, these springs are so commonly lost by customers that the springs are sold in multipacks of 5 or 10 springs. Because Shimano twist shifters are much less common that SRAM, I might ...
alotalot's user avatar
  • 349
5 votes

XTR 9100 left power meter on XT 8100 crankset

Since Ted covered the main points, I shall provide some supporting information and visual aids, as promised. The XTR FC-M9100 and -9120 cranks feature a single-bolt attachment for the left crank arm. ...
MaplePanda's user avatar
  • 15.6k
5 votes
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How to remove deep scratches from Shimano Dura-Ace crank?

One problem is that the crankset is anodized black. Strictly speaking, anodization is when we use electric current to change the thickness of the oxide layer at the surface of a metal like aluminum. ...
Weiwen Ng's user avatar
  • 32.5k

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