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11 votes
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Cause of broken spokes (pictures included)

The grooves/enlargement shown at the hub are all normal. The path to a wheel that doesn't break spokes is use premium quality spokes (DT, Sapim, and Wheelsmith are the usual poster children), set ...
Nathan Knutson's user avatar
10 votes

Does chain tension change how hard/easy it is to pedal?

If the tension is too high, the drivetrain will bind. If it is too low, the chain will drop (which is dangerous on a fixie, since it can catch and lock up the rear wheel relatively easily). You ...
Batman's user avatar
  • 46.2k
9 votes

Cause of broken spokes (pictures included)

Another common cause for spoke breakage at the J bend is low spoke tension, or preload. As you ride, the bike momentarily "hangs" from the topmost spokes on the rim. Because its a dynamic ...
Criggie's user avatar
  • 123k
8 votes

Single speed chain tensioner comparison

You should never use a sprung tensioner when you have a choice. They add fragility and complexity. They exist only to allow single cog drivetrains to work with dropouts that don't allow chain tension ...
Nathan Knutson's user avatar
7 votes

Chain noise, fixed gear

Looks a little tight. There should be +/- 0.5 inch vertical movement of the chain possible halfway between the sprockets. Park tool has a great video on single speed chain replacement: ...
Argenti Apparatus's user avatar
7 votes
Accepted

Is it common for the left side spokes of a front disc wheel to have more tension than the right side spokes?

The side with the disc is dished in more than the other (that is, the spoke flange is closer to the hub's centerline), so yes, I would expect it to have higher tension.
Adam Rice's user avatar
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7 votes
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Is this spoke tension too low?

The left to right side tension numbers you have are thoroughly normal. 70%-ish is where a lot of disc wheels land. Once you're actually building the wheel, as opposed to planning it, you're only ...
Nathan Knutson's user avatar
7 votes

What is the reference unit of the kgf reading on the Park spoke tension chart?

Kilograms force. It is tension equal to a weight of that many kilograms pulling on the spoke under earth gravity.
Nathan Knutson's user avatar
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
6 votes
Accepted

Correct spoke tension for DT Swiss EX 471 26" 32h rim paired with Wheelsmith DB 14 spokes

I believe DT has a blanket recommendation of 1200Nm for all their rims, or 122 kg-f. You could email them to corroborate but that number should be safe. Use the tensiometer chart for the thin section ...
Nathan Knutson's user avatar
6 votes

How to increase tension of rear derailleur cable

You started with too much slack for the barrel adjuster(s) to take up. Note you have one on your derailer and one on your shifter, and they both do exactly the same thing, so maybe by using both you'...
Nathan Knutson's user avatar
6 votes

Worn out chainring or missing tension

I will focus on the chain tension part of the answer, as your big chainring is clearly worn out. However, do note that increasing the derailleur spring tension wouldn’t stop the chain skipping on the ...
Weiwen Ng's user avatar
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6 votes
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Worn out chainring or missing tension

I suspect the symptom of slipping could be mitigated for a while by increasing chain tension, but it would only be a short-term fix. Here's a trace of one of your photos highlighting the teeth. See ...
Criggie's user avatar
  • 123k
6 votes

Spoke Tension Drive Side and Non Drive Side

Yes, you understand right. When you have a manufacturer's max tension spec to work with on any rim, offset or not, make that number be the target tension on the higher-tension side (drive side rear, ...
Nathan Knutson's user avatar
6 votes
Accepted

How to tighten chain on Kalkhoff Image 5.B Season

Given that the bottom bracket does not seem to be eccentric, and there is no chain tensioner of any kind, I'm trying to make a guess based on the photo's. This looks like it could be a bolt used to ...
Berend's user avatar
  • 580
5 votes

Why do my rear caliper cable becomes loose after some squeezes in the brake lever?

If you fasten the cable anchor with the quick release at its "tight" position and then it's able to slip into a "loose" position, that sounds like a likely culprit to me. I haven't encountered a ...
Nathan Knutson's user avatar
5 votes

Worn out chainring or missing tension

Chain tension is set by the springs in the derailleur. Some derailleur models have a tension adjustment in the upper B-pivot, but I think this is to adjust the range B-screw rather than change the ...
Argenti Apparatus's user avatar
4 votes
Accepted

Chain on singlespeed tight, pedals won't turn backwards very freely - is this an issue?

Yes, overly tight chain does accelerate wear on other parts of the drivetrain. The rear hub bearings are not designed to work under the load described here and if ridden like that for extended periods,...
Wsal's user avatar
  • 601
4 votes
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Chain noise, fixed gear

The chain was not straight: wrong rear wheel hub size for my frame! By calculating the chainline of my crankset and the rear frame dropout I noticed it was off by 5 mm. My frame has a weird 126mm ...
d.lime's user avatar
  • 211
4 votes
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What can be done wrong changing the chain in a single speed?

The photos show that the contact surfaces of the cogs have been worn to match the old chain. The new chain does not match them perfectly, which is the reason to the noise. For some reason ...
ojs's user avatar
  • 22k
4 votes

Cause of broken spokes (pictures included)

The hub holes are elongated a little bit but I would not be concerned. It seems to me a pretty typical amount of deformation. I would reuse the hub but I would re-lace the hub with the same pattern. ...
BetterSense's user avatar
  • 3,366
4 votes

Alfine shifter cable tension increases over time

I'll note even some potential problem causes that might sound stupid, but in my experience, even a quaified mechanic can sometimes make a mistake, and not take something trivial into consideration, so ...
bikegremlin's user avatar
4 votes
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Slight Difference in Spoke Tension Between Inner and Outer Spokes on Straightpull Hubs?

Yes, it's normal and you correctly understand why. Some straight pull hubs can create more variance in bracing angle per side than a j-bend hub would. Other straight-pull designs (Velomax/Easton comes ...
Nathan Knutson's user avatar
4 votes
Accepted

Is it normal to need to re-tension drive belt (Gates CDN) after few days?

The belt itself is supposed to be very dimensionally stable, which more or less bears out in reality. Eccentric BBs are fine in terms of being a sound design and way of tensioning the chain, but ...
Nathan Knutson's user avatar
3 votes

Single Speed / Fixie - Chain tension / uneven tension

I'm going to disagree with Mike and say that chain is far too tight. I race singlespeed MTB and have a fair amount of experience setting chain tension. In the fixie/singlespeed world; a loose chain is ...
jc allen's user avatar
  • 689
3 votes

Chain on singlespeed tight, pedals won't turn backwards very freely - is this an issue?

Over-tensionning the chain is never a good idea. Except maybe for the unscrupulous mechanic who will be the first to make some profit. It puts a lot of strain on the chain and mainly on the bearings....
Carel's user avatar
  • 8,299
3 votes
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What should I do about a tensioned/trued wheel that lost significant spoke tension after first use?

Yes, it’s normal for spoke tension to decrease when the tire is inflated. First of all I’d use much more tension and try to get it more even. Currently you have about 30% difference between slackest ...
Michael's user avatar
  • 26.8k
3 votes
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Rear Derailleur wire sags completely in higher gears

What you describe suggests friction in the rear housing loop. It fits with the problem getting progressively worse, and with the apparently slack cable, presumably along the downtube or chainstay. ...
Nathan Knutson's user avatar
3 votes

Single speed chain tensioner comparison

Brakes If you have a coaster brake, then a trackend is the only safe way to tension the chain. Otherwise your braking efforts are initially wasted in the tension spring, which can be damaged by the ...
Criggie's user avatar
  • 123k
2 votes
Accepted

Why do my rear caliper cable becomes loose after some squeezes in the brake lever?

The problem was with the cable/housing. I would probably pinpoint the source as the housing which goes from the frame to the caliper. I could probably have done a cheaper fix by replacing just the ...
gstorto's user avatar
  • 343

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