If I'm riding on the road, and there is a red light but a walk signal in my direction, should I go? I frequently come to stop lights in which there is an all-way stop and a pedestrian signal. I always stop at such lights, but I'm wondering if I should then bike slowly across after determining that it is safe and I will not be interfering with any pedestrians who are crossing, or if I should wait until the light turns green just as I would were I driving a car.

Only cross if you are walking and pushing your bike.  If you are riding, you are a vehicle and generally you are required to obey all traffic control devices in the same way any other vehicle operator is. There are exceptions, like the Idaho Yield laws, but generally you have to behave like a car.

The other thing to think about is that the more you behave like a vehicle, the more predictable you are, and the more predictable the behavior of other vehicle operators will be.


How To Prevent Holes Around The Inner-tube Valve? In the last two months I have experienced something new: three inner-tubes (700X25) have popped with holes immediately around the valve and on the same side of the tube as the valve. I suspect there is a deficit of support for the tube as the hole in the rim for the valve is slightly larger than necessary (1-2mm bigger in diameter that I would think best). Should I replace the rim-tape? How may the proper support be imparted to the inner-tube around the valve?

I had a spate of these; all the tubes had an elliptical, smooth rubber section immediately around the valve, and then a weld joining this to the body of the tube. The failure was always at this weld, and it looked as if the tube had herniated (bulged out in a single spot before bursting there).

After ruling out tape problems, burrs, sharps, valve hole diameter etc. - I finally figured out the problem.

The elliptical section is less flexible than the main body of the tube, so after pushing it above the bead as Zippy suggests, it wasn't fully descending to sit flush against the rim. This left a void between the rim and the less-flexible part of the tube around the valve; the more flexible section of the rim then tried to expand around the weld to fill this gap, and that's where it burst.

The solution is (touch wood) to pull the valve back down after the tyre is seated and the tube partially inflated, and tighten the nut more than usual (and then slacken off).  When the tyre is fully inflated, double-check that there is no bump near the valve, that the bead is seated properly there, and that the valve doesn't move if you tug it towards the hub (not too hard!).


How to carry a MTB on one's backpack? Sometimes I want to ascend a steep (say, 50%) slope, where is impossible to ride and awkward to push/pull the bike.

I tried various ways of carrying the bike:

Lifting it just 10 cm above the ground - good for very short sections
Lifting it with one hand to shoulder height - good for short sections; the arm gets tired quicky
Holding it above my neck with two hands; the arms get numb quickly
Putting it on my backpack; the back starts to ache at random places, as if warped

I imagine the last idea, with resting the bike on the backpack, is the only usable one for long sections (say, 30-60 minutes walking). Am I right?

Which way can I secure my bike on my backpack, so the back ache (and supposedly damage) is minimized?

Update: I had a half-full 35-litre backpack at the day I had this problem. I am willing to fill my pack with light bulky stuff if needed, but I don't want a bigger pack: 35 L seems enough for maximal journeys I want to do; any bigger and it starts to be annoying.

My friends and I have hiked a lot while carrying our bikes. What I've found that works best is:

go to the non drive side of the bike
drop the non drive side pedal down
left hand on the left fork lower
right hand on the non drive side crank arm
lift whole bike and place bottom tube behind your neck

This works because:

bike is central on top of you and you can easily remove one or both hands whenever necessary
you don't get dirty because the drive side is away from you

To lift the bike, your hands should go to the two red spots:

Also see How to shoulder a bike?


Handlebar-mounted "turn indicator" that can pair with a smartphone for turn-by-turn GPS navigation So far I've been using my Android smartphone and a combination of Strava and Google Maps for navigating/recording my routes. This works reasonably well, but as I've been going on longer and longer rides I'm getting fed up with having to take my phone out of my pocket to check whether I've missed my turning.

I've tried mounting my phone on my handlebars, but this isn't a great solution for several reasons:

It's bulky and vulnerable to getting smashed in a crash
The battery quickly runs flat if I leave the display on for navigation
It's hard to read the display in bright sunlight

I've looked at various cycling GPS units which seem to mainly fall into two categories:

Small, relatively cheap units that record performance stats (distance, speed etc.) but don't offer any navigation functionality. I'm not really interested in these features since I can already record most of the information I want using my phone.
Bigger, more expensive units with colour screens that offer route planning and turn-by-turn navigation. My phone already has a nice big color touchscreen as well as a GPS receiver so I find it hard to justify spending ~£200+ on one of these.

All I want is a small, dedicated "turn indicator" that I can mount on my handlebars and pair with my phone (perhaps over Bluetooth).

So far the closest thing I've found is the Schwinn CycleNav. However there are lots of angry reviews on Amazon claiming that the app is no longer supported on current versions of Android/iOS. If so then this rules it out completely for me.

By far the nicest-looking "turn indicator" solution I've seen so far is on the Hammerhead. It's reasonably priced for a cycling GPS unit, although I still feel like buying another GPS receiver would be overkill. I also have some reservations about their Android app, which has some quite poor reviews.

There also seem to be a few relevant products at the crowdfunding stage. In particular Beeline comes close to the idea of a dedicated turn indicator. However it doesn't actually do proper turn-by-turn navigation - all it gives you is the bearing and distance to your destination, which is no good for me.

I'm sure I can't be the only one looking for a solution along these lines. Does anyone have experience with the options I mentioned above, or any other recommendations?

I've had a phone in a bumper case come off the handlebars several times without damage. But my handlebar mount kept getting broken in the bike shed at work so I  switched to a top tube bag (which also holds a tube and basic tools). The low light readability is still an issue, but you're over the top of it a bit more which helps. Where I put tools you could put an extra battery. The bag is firmly attached to the bike so won't come off, and the location means it's highly unlikely to hit anything. They're cheap so it's worth a try. This way there are no worries about device/phone/app compatibility.


Periodic Maintenance Task for Bike Commuters What are the periodic maintenance tasks (weekly, monthly, annual, every X miles) that anyone who relies on a bike for transportation (typically in urban/semi-urban environments) should be performing? Ideally stated in terms of miles travelled (where applicable).

Mostly it depends on where and how far you commute, and road conditions (sandy, snow, salt etc etc).

At a minimum what I do is:

Daily: check tire air pressure.

Weekly: Check brake pad wear, tire wear, clean/wipe down entire bike

Monthly: Check chain tension, chainring/cogs for wear, lube chain, adjust brakes, oil all pivot points on derailleurs, brakes etc.

Annually: complete tear down, inspection and reassembly with synthetic grease on all bearings.


Is my bike a good fit? I am a woman and I have been wanting to get into cycling.

A few summers back I bought a gravel bike. I bought it new from a local bike shop that I trusted. The bike was considered a 'medium' (5'6-5'9 ft). I am 5'4 and because I am still fairly new at this I thought the size wouldn't be a big deal. Plus, everything seemed to fit me fine and comfortable when I rode it around in the parking lot.

The thing I have noticed though is the top of the handlebars and the saddle are the same height, which is different than what I have seen, where the saddle is higher than the bars. I have had my seat height adjusted by a advanced road biker.

Once I took it home and began using it, I realised I couldn't go a mile without my rump being sore and numb. So I got a few quality pairs of distance cycling shorts. I also angled my seat down slightly. Once that wasn't enough I purchased chamois cream. Then I purchased a new bike seat for a very pretty penny. After all of these changes, I still only have comfort for about 15 miles and then I go completely numb in places I think we all would prefer to have feeling.

Last summer I sort of sucked-up the pain and kept biking almost every day, 20-25 miles. Now, I want to start biking even more but am finding that I am losing the joy in biking because I am always in pain or completely numb when biking.

Does anyone have any more tips for me? I have seen that getting a bike and saddle fitted can be pricey so I have been holding off on getting professionally fitted, and am wondering if it all may be because my bike is just a size too big for me. What do you think?

I think it's likely that the frame is just to large for you. A medium frame is generally too large for a person 5'4" (approx. 162cm) in height.

What's going in is that distance from the saddle to the bars is likely too long, causing you to have to lean forward too much, which is causing your pelvis to rotate forwards also.

When sitting on a bicycle saddle properly, the bones at bottom of your pelvis should be taking you weight on the wider, rearmost part of the saddle. There should not be pressure on the perineum or points further forward. When the pelvis rotates forward weight is transferred from the pelvis onto the perineum. Apart from being painful, that cuts off blood supply and pinches nerves which causes numbness.

The proper solution is to get a frame a size (or two, depending on your body proportions) smaller. A potential solution is a significantly shorter stem to pull the handlebars back and allow a more upright riding position.

You can try getting a bike store to try to fit the bike to you, including playing with stem length, but personally I'd look for a replacement bike in a smaller size. Try some different bike stores and see what recommendations you get for sizing and fit.

At least in most US states bicycles stores are considered essential businesses, and bicycle business is booming. You may easily be able to sell your current bike to offset the cost of a replacement.

Updates based on photo and info in comments:

As others have said saddle height is too high, your arms are straight in the first photo and your ankle is raised with the pedal at the bottom in the second. Elbows should have a bend and foot should be flat with a slight knee bend.

Given that, you actually look a quite cramped on the bike. Notice your back is straight and the angle between your arms and body is less than 90 degrees. Your knees look very close to the bars. I think the fore-aft saddle position is way too far forward, it should be set to get the pelvis in the right position relative to the feet NOT to adjust reach to the bars. Set the saddle height properly, then with a pedal straight forward your kneecap should be vertically above the pedal axle.

I think excess saddle tilt may in fact be causing you to sit too far forward on it moving you pelvis bones off the wide part at the rear.

The whole bike does not look obviously big for you, so this looks salvageable. What I would do is sort out your saddle height position and tilt first, and get you sitting in it properly. Then figure out where a comfortable bar position is for you, then achieve that with a shorter stem and possibly shorter reach bars. You can also rotate the bars back a little to get a comfortable angle of the drops under your hands

It looks like you want to be in a less aggressive, more upright position so your bars will be approximately level with the saddle, which is totally fine. Once you are feeling more comfortable on the bike you can work on some back flexibility and lower the bars if you want.

You may want to enlist the help of a good local bike store to help you get set up right. You may not have to pay for a proper bike fit. A good store should help you get these basics sorted out if you buy a new stem and bars through them.

Here's a good video on basics of bike fit. Contrast your position on the bike to those shown in the video.


The palms of my hands really hurt I understand that the pressure on my hands causes it.
I also understand how the nerves run through my hand.

What I don't understand is how to implement the advise of, "Take the weight off your hands"

A fellow told me, "Put 90% of your weight on the pedals, 10% on the seat, and barely touch the bars with your hands." I dunno how to do this!

With the seat up in order to get a full pedal, the angle of your body is going to naturally push down on your hands. The only way I know to "put weight in the pedals" is to stand up.

Short of getting a raised handle bar or lowering my seat, how do you get the weight off your hands? Is there some kind of posture magic I can't figure out?

You are correct that a leant-forward riding position will naturally tend to make a rider support some of their weight with their arms and hands. The more rotated forward the rider is, the more weigh the arms tend to have to support - which is one reason tri-bars have forearm rests.

Good core strength is what allows a rider to take weight off the arms. Strong lower back and abdominal muscles support the torso, taking weight off of the arms. You can try doing some core strength building exercises (which will likely make you a stronger rider and help prevent injury as well).

You should look at your fit on the bike, you may in fact have the bars too far forward and down. Raising and pulling them back may help while you build core strength.


Are Shimano R440 road flat bar shifters compatible with a mountain bike front derailleur? The Shimano shifter flat bar series have the same cable pull length than the mountain bike shifters.

Is this series compatible with a mountain bike front derailleur, Deore, for example?

There's a great thread here that describes some of this. Here's the meat of it though:

  Shimano's assertion that you need to use "flat-bar" front derailleurs
  with "flat-bar" shifters is false.

  When working with Shimano, "flat-bar" shifters are really just
  mountain-bike shifters in different colors. This doesn't make a
  difference for the rear derailleur (Shimano has standardized the cable
  pull across all of their shifters), but there's two different cable
  pulls for the front derailleurs. "Road" front derailleurs require less
  cable movement than "mountain" front derailleurs for the same amount
  of lateral cage movement.

  This has a couple consequences:

  1: operating a "mountain" front
  derailleur with a "road" shifter will result in insufficient cage
  movement to make the shift. This is rare in the recumbent world.

  2: operating a "road" front derailleur with a "mountain" shifter will
  result in the shifter jamming before the internal ratchet catches,
  meaning the chain will shift but immediately return to its starting
  position. In other words, the shift fails. If the shift succeeds,
  often the shifter will jam at that spot and not allow the shift in the
  other direction. This is very common in the recumbent world.

  the longer pull of the "flat-bar" or "mountain" front derailleurs makes for lighter pull at the shifter when using SRAM twist-grip
  shifters. This can be an advantage for people with slippery hands
  and/or weaker hands.

  "Flat-bar" front derailleurs also have cages that better match the
  larger diameter chainrings typically installed on road bikes.
  "Mountain" chainrings are typically smaller, and trying to get a
  "mountain" front derailleur to work on larger chainrings often
  involves compromised adjustment or hand-modified cages.

  My favorite "flat-bar" front derailleur is the Shimano FD-R443. (This
  is roughly Sora/Tiagra level parts: cheap, durable, and relatively
  attractive.) It's since been superceded by the FD-R453, which has a
  taller inner plate to match newer Shimano cranksets, but I like the
  FD-R443 for its greater adaptability to different chainring
  combinations.

  I've been using the FD-R443 on several bikes, operated by Shimano
  Deore LX and XTR and SRAM Half-Pipe Attack shifters. It's always
  worked flawlessly.

So no, not really. You might be able to find a combination of gearing, derailleur, and cable pull that will work, but you're probably still better off finding a matching set.


Shifters compatible with: SG-3D55 (Shimano Nexus 3 speed - disk brake - internal gear hub) I am planning to buy the SG-3D55 internal gear hub.

According to this forum post, the SL-3S35 is compatible. But what about the other 3 speed nexus shifters? I am finding it hard to find any documentation.

Also I am in the UK, so hoping to source the shifter for here if possible. I am already resigned to having to import the SG-3D55 from the US, as I can't find it in the UK/Europe.

Any specific or general wisdoms gratefully appreciated.

User6527 is wrong there. You can not use derailleur shifters due to the different cable length that is pulled or pushed to shift to another gear. You can not use other brands' shifters either for the same reason.

The shifter you mention yourselve is available in black and silver, and both with and without integrated brake lever. There is also a 'cheaper' version: SL-3S41E.

I thought there was a retro alternative as well, but I can't find it. Not online, and even not at our bicycle parts wholesaler.


Distance discrepancies between Strava and bike computer I have an established 16 mile mountain bike loop I've been riding for a long time. I recently purchased a Magellan Cyclo 315 bike computer which I load files to Strava Premium from. Everything works great except the distance data. The distance value on the computer is always very close to 16 miles, but when I upload the data to Strava (.gpx file) the distance is between 15.2 and 15.4 miles. Any suggestions on how to correct this problem?

It might have to do with how frequently the computer writes your GPS location to file.  To optimize storage some write out a location to file once every few seconds, but carry out its own calculations on a higher resolution dataset in-memory before purging. If your route is quite twisty this can result in a shorter distance as Strava (and everyone else) assumes a straight line between locations in a .gpx file (this is really the only workable assumption).

Check your bike computer settings, some allow you to specify the recording resolution (e.g., once per second). The downside could be that your computer may not be able to store as many tracks as a lower resolution setting (e.g., once every 5 seconds).


Can we fit an 11 speed cassette to new Shimano XTR 12 speed hub? I'm looking for a very silent hub. Upon searching, I came across with Onyx hubs which definitely has no sound. I really like it, but my budget doesn't. So I've searched a little more and found Shimano's new 12 speed XTR hub with Scylence tech which cost half the price compared with Onyx. My problem is, it's 12 speed with new Microspline freehub body. I have an old XTR 11 speed setup.

So there lies my question, can I fit an 11 speed cassette to a XTR 12 speed hub?

I know there's a spacer but I only see an upgrade from lower speed to higher like 11 speed to 12 speed not downgrade 12 to 11.

There seems to exist 11-speed microspline cassettes, meaning you can have a 11-speed drivetrain with a silent Shimano microspline hub. For example, here is a description I found at one webshop:

The special version of the XTR cassette is based on the 12-speed version with 10-51 teeth, but comes without the largest sprocket to offer enough space for the Wide Flange Shimano XTR FH-M9125-B rear hub (product code: 2278419) and thus for more stable wheels. <...> You even don’t need a special chain or a special shifting system, as the 9100 series shifters can be easily converted from 11 to 12-speed thanks to the Mode Converter. <...>
Details:
• Hyperglide+ cassette 11-speed
• For singlespeed and double chainring systems
• Can be integrated into a compatible 12-speed XTR system
• For Shimano Micro Spline freehub
• Compatible with Shimano 12-speed HG+ chains, such as Shimano CN-M9100 (product code 2273556)
• Material: steel, titanium, aluminium
• Aluminium spider (anodised)
• Incl. aluminium locknut
• Weight: approx. 299 g
Gear ratio: Shimano XTR 11-speed 10-45: 10-12-14-16-18-21-24-28-33-39-45 teeth
ATTENTION: Even though it is especially developed for the Shimano XTR FH-M9125-B Wide Flange rear hub, the XTR CS-M9110 11-speed cassette can also be mounted on standard XTR 12-speed hubs – losing the advantage of more stable wheels thanks to a wider hub flange.
ATTENTION: Only compatible with Shimano Micro Spline freehub. Not compatible with current M900 components and other Shimano 11-speed groups.

So the answer to your title question is "yes". I am unsure from the description if you'll have to replace the shifter and/or derailleur as well in terms of how much the new cassette is compatible with older XTR derailleur indexing steps.


Is it possible that the gears switched from left to right? I'm 100% sure that my gear levers on the right side are for my front gears and the ones on the left side are for changing the rear gears.

After a muddy ride today it seemed that this changed. I was pressing the right levers to change the front gear and the rear gears started to change instead.

Is it possible? I know I have to take it for maintenance, but I wanted to check before so that the guys there wouldn't think I'm crazy.

My bike is Giant ToughRoad SLR GX 3 2018 and I had it for about 8 months during which it didn't have any issues.

The standard setup is left for front and right for rear for gears.

For gears you would need special left rear and right front shifters, which are not manufactured. It is very unlikely that you had those, and they converted to normal shifters during one ride, at the same time as cables rerouted themselves.


Is climbing easier on a light road bike or one with lower minimum gearing? I am looking to get my first road bike and I am deciding between a 23.2 pound road bike with a minimum gear ratio of 34-32 or a 20.7 pound road bike with a minimum gear ratio of 34-28 and I was wondering which bike would be easier to climb with.

Lower gearing (or gearing in general) is generally more important than the bike weight for climbing (for most riding as well, sans high level racing). Both of the gear choices are pretty low and you'd need a pretty steep hill (or towing a lot of cargo) in order to need the lower gear over the slightly higher lower gear. As Criggie points out, there are other factors to consider other than weight -- ergonomics, build quality, etc. which can have a more profound effect on how you ride.

A difference of 2.5 pounds is easily within the fluctuation range of your weight over the course of a few days, and is likely on the order of a percent or two of the total bike+rider weight anyway so you can basically ignore it.

As the comments say, you can switch your gearing in the back fairly easily, but this may require a new derailleur depending on capacity and cog size limits and a new chain (this is a relatively easy replacement). Note that you have to give something up for a fixed number of cogs and different gearing combinations (such as the spacing between shifts, max or min gear). So, if the largest cog is 32 in one case and 28 in the other and they have the same smallest cogs, you'll likely have bigger spacings between shifts on the larger cog one. Ideally, you'd try them out and see what you like better.


App to use Mobile phone (samsung S4 mini) as bicycle computer What apps to use if I want to turn my old phone into a bicycle computer? I want to view basic info all the time such as speed, trip time, total distance traveled etc.

Are there any apps which will save energy while showing these details?

This is possible.

Firstly, it depends on your idea of "old"   For some users thats any phone over five minutes is old, and for others old means a flip phone from the 90s.

Assuming you have an android-based or ios-based phone that works and has a decent battery life then you're pretty much set.  Both will run the Strava application, which looks something like this:

As @dancek says, the home screen is not configurable, so you will only see average speed for the whole ride, and instant heart rate/cadence rate if you have the sensors.   Time and Distance are counters

This is the screen that shows up when you stop.  The map with track at the top can be displayed full-screen while riding, and if you have planned a route the track is overlaid on the map as well.

Later analysis can be done on the info - here's the link for that ride:
https://www.strava.com/activities/681005599/analysis
Note I had a HRM but no cadence sensor.

This is the RUN view if you're into that kinda sport.

If you have an applewatch there's a thing for that, but I have no experience of this.   It looks like this:

Both of those screenshots show heartrate.   A phone can't do that alone - you need a heartrate sensor.  Phones with ANT+ radios are better than bluetooth sensors because the batteries last for 4-6 months, whereas bluetooth sensors are a much shorter runtime.   Also note, that phones with a "pulse meter" are useless for this purpose.

There are ant+ cadence sensors too - often a little box that straps onto a chainstay, and a small magnet on the end of a crankarm that passes near the sensor.

If you want to see your phone while riding that gets messier.  Personally I keep my phone in my pocket with the screen off.

Otherwise you'll need a handlebar mount, or a top tube bag, or both.  Its a good idea to bring a USB battery pack and cable for your phone, because a phone that runs for a day of normal use might only get 2-4 hours of riding time before its flat.

Right-angle USB cables can help organise things too.

Windows phones are lacking in this area - a good answer is Windows Phone as a Bike Computer - What is the current State of the Art?


Deore Derailleur w/ Tiagra STI Shifter Compatibility I have Shimano Deore RD M591 Rear Derailleur (http://www.jensonusa.com/Shimano-Deore-M591-9-SPD-Rear-Derailleur) that I am having trouble dialing in shifting when used with Tiagra 4700 2x10 STI shifters (http://www.chainreactioncycles.com/us/en/shimano-tiagra-4700-2x10-speed-sti-shifter-set/rp-prod137777) and a SLX 11-36t 10 speed cassette. I was working off of the general hypothesis that a 9 speed mountain derailleur would have the same pull ratio as the 10 speed STI shifters. I can adjust shifting to work as needed for the first 3 highest gears, but then when I shift beyond that towards the "easier" rear cogs it is consistently skipping over a cog (from 3rd to 5th for example). This continues up to the 10th cog, shifting two gears for every one click of the shifter. If I adjust cable tension so shifting is smooth in the middle or low end of the gear range, it is then not accurate at the high end of the gear range.

My goal was to extend my climbing gear range as much as possible so I could take my winter/cyclocross frame and turn it into a gravel bike capable of climbing some steep Vermont dirt roads.

Any thoughts or ideas appreciated. Thanks!

I was working off of the general hypothesis that a 9 speed mountain derailleur would have the same pull ratio as the 10 speed STI shifters.

That's true, except for Tiagra 4700, which rather inexplicably uses the 11 speed pull ratio.

See https://bicycles.stackexchange.com/a/52277/24228

  Presently there are two different 10-speed Tiagra generations, 4600 and 4700. (So the STI from one is ST-4600 and the other is ST-4700, etc). 4600 uses the same classic actuation ratio that all pre-11-speed Shimano road groups used other than first generation Dura-Ace. 4700, however, is an oddball group. It's 10-speed but uses the new 11-speed actuation ratio


Is graphite grease suitable for bicycle bearings? The Wikipedia article doesn't explicitly list the applications of graphite grease. Would it be suitable for bicycle bearings and threads?

Furthermore, I went ahead and purchased a single package (the same price as the lithium grease). It says (translated):

  Water-resistant calcium anti-frictional grease. Contains 10% powdered graphite. Intended for lubricating sliding parts (like springs, chains, ropes), which are susceptible to quick wear, contamination etc. at temperatures from -20C to 65C."

Daniel R Hicks's answer-as-a-comment:

  As it says, it's intended for lubricating sliding parts. Not ideal for ball bearings. –  Daniel R Hicks 2015-06-23 11:48:24Z

  "Dry lubricants" are not a good choice for ball bearings, as they do not exclude water. The #1 role of bicycle bearing grease is to keep water out. –  Daniel R Hicks 2015-06-25 12:05:18Z


Tires shedding black threads Around the rim of my Bontrager tires, which are about 6 months old, there are small thin rubber thread-like fibers coming off. The brakes do not rub. I ride a Trek 7100 on asphalt roads, with several tall hills I ride down. Do I need to replace the tires?

The word is SPRUE and can present as a short rubber "hair" 1-2 milimetres thick, or a long thin straggy line around the tyre, somewhat like a fish fin.

If your rim tyre is too narrow for your tyre then its possible for the edge of the rim to wear on the tyre.  This could produce threads that really are thread, instead of rubber.  I've never seen this on road tyres, but its a rare possibility on oversized MTB tyres on hybrid/cruiser rims.


Shimano RD TX55 Tourney TX 6/7 Speed Compatibility I currently have a 7 speed bicycle, and recently changed my rear derailleur to a Shimano RD TX55 Tourney TX for a 6/7 speed compatibility. My shifter is Shimano Rapidfire for 7-speed.

The current problem that I have is that when I shift into the 6th, 5th, 4th, 3rd, and the 1st sprocket it becomes unstable. The RD is not properly aligned with the gears. The 7th sprocket does not have any problems. The 2nd sprocket on the other hand, I have to shift the shifter from 2 then change it to 3 only then it becomes stable in the 2nd sprocket.

Upon observation, I suspect that the RD is more towards for a 6-speed sprocket due to their alignment on the sprockets.

Is this true or is there some way to adjust the RD to fit the 7-speed sprocket?

Additional information:
1. The cable is tight, not slacking.
2. Barrel adjuster is 0, at its initial position.

Edit: First question, why did you replace the derailleur?

Rear derailleurs don't really care about # of speeds - its the shifters which change the cable pull to move them around (so mixing shimano and sram can cause problems due to different amounts of cable pull). By RD not aligned with gears, do you mean the hanger / cage are bent? If so, go to your LBS and get them to unbend it / replace the hanger. If the rear derailleur is in good condition, you just need to adjust the cable (assuming its in good condition) to be taut when in the smallest cog (I lightly use pliers for this - make sure that the cable is actually being held in place) and then use the adjustment screws.

Have you adjusted your high low limit stops and indexing adjustment and btension?
See http://sheldonbrown.com/derailer-adjustment.html for an overview (or one of the various youtube videos on doing this)
http://www.parktool.com/blog/repair-help/rear-derailler-adjustments-derailleur

Also see the thread here: What are the most common causes for hysteresis in the rear derailler?


Anyone know of 3x7 brifters with internal cabling? Kind of similar to this question (sorry for the repetition).

I have an old (beloved) specialized A1 with Shimano RSX shifters. They periodically suffer from this problem where they stop shifting. I'm getting a bit frustrated with periodically having to disassemble or flush out with solvent. So I'd like to treat myself to some brand new, preferably with internal cabling.

Does anyone know if there are shifters with internal gear cabling for 3x7? I've googled around a bit but didn't find anything.

It's a hack, but you can do this with the current Claris ST-2400 3x8 levers using an alternate cable mounting position on many "classic" shaped Shimano rear derailleurs. (Make sure whatever you're buying says 3x8.)

Sheldon Brown goes into this briefly here. It tends to work fine in this combination (8-speed shifters on 7-speed.)

Note that all shift-housings-under-the-tape STI levers use the Super SLR brake cable pull standard. They pull slightly more cable and so if you hook them up to calipers not intended for them, the mechanical advantage will be skewed such that it feels firmer but is less powerful. It's not generally a dealbreaker and there are a lot of bikes in the world set up like this, but it is noticeable and I've seen the results be mediocre enough that I tend to avoid it when I can.


To Cold Set or Not To Cold Set? I have a Trek 620 (Reynolds 531 lugged steel frame) from the mid-80s the rear dropouts are spaced at 126 mm. I'd like to be able to run an 8- or 9-speed cassette and I was wondering about the issues involved with running a modern road hub with 130 mm spacing without adjusting the frame spacing.

It seems to me that the rear triangle would have the ability to flex 4 mm without needing to be cold set – at the expense of a small misalignment of the dropouts.

Are there problems with doing this? Other than the slight hassle when installing the rear wheel?

Would it impact the value of the frame – the bike is a rider, probably not a candidate for a restoration (frame could use repainting and I'm not sure the components are original, the wheels definitely are not)?

No need to cold-set.

I have a BSO with the same problem. The rear dropouts are about 6mm too close for the hub. I can just flex them apart and let the hub in.

The misalignment of the dropouts would be virtually nonexistent at 4mm flex.

If you remove your wheels often, and putting the wheel on is a pain, it might be worth cold-setting your frame. Other than that, don't bother.


Loud cracking noise after installing new chain I did some work on my Rohloff bike today, installing a new chain & chainring and reversing the sprocket.  When trying out the bike afterwards, something in the drive train was making a loud cracking noise under load.  First I thought it was the hub, but after a while, I tracked it down to the new chain I had put on.  Putting on the old chain was the only thing that made the noise go away.

What would cause this kind of noise on a new chain?  Did I break it or did it came broken out of the factory?  Should I try to get a refund?

You can hear the cracking here:

My guess is you have some tight links that are making noise as they go over the sprocket. Those can probably be fixed easily.

See this Park Tool video. Tight links are addressed at about 10:35.

It might be that you did not join the chain links properly. What method was used to join the chain? A master link or rivet?

You can also see the chain tensioning advice in the Park video to check if that is the cause.


Why the narrow wheels on comfort bikes? Assumptions:

With city bikes (comfort/dutch bikes, like the one on the picture below) weight is not a priority for the design.
City bikes use narrow tires
For the same pressure, a narrow tire exhibits more rolling resistance
Air drag is an order of magnitude lower than rolling resistance at speeds up to 20 km/h
Thin tires puncture more often and require pumping up more often

So why do those bikes use thin tires, and not 2" slicks?

I think there are a couple of flaws in your knowledge that help determine the prevalence of skinny tires.

Firstly, narrow tires exhibit significantly less rolling resistance than larger volume tires. This has benefits and drawbacks, with the benefits being easier commuting due to less friction. The drawback is that there is a smaller contact patch with the ground and hence less grip, but on smooth paved roads, asphalt etc. this is not a large problem. Also, slick tires increase the grip due to more rubber contact and less grooves between knobs compared to a similar volume and diameter knobby tire.

Aerodynamics is not a huge factor in the equation, as you pointed out, since low speeds around 20km/h are only marginally effected by air.

On the issue of air pressure, I think the pressure-for-pressure comparison between skinny tires and larger volume tires is a bit of a misleading statistic. Skinny tires run exceedingly high pressures - racers are all known to use upwards of 80psi and as high as 120psi! Compare this to a larger volume tire, like that on a mountain bike, and pressures of around 30psi are about the norm. MTB tires like this are often rated for much higher pressures than they will ever need, but many will take use of this in order to use a MTB tire on the road, for example (I often run 50psi on 2.1" MTB tires for more efficiency on the road). Pressure ratings on tires simply refers to the uppermost limit of safe use before there develops a significant risk of tire blowouts or some other failure. However, the relationship between rolling resistance and tyre pressure is completely different for road or MTB use. On a MTB, lower pressures offer lower resistance due to their ability to deform and mould to the terrain, essentially flattening out the ground. This effect is useless on a paved road, where the surface is almost completely smooth. So on a road bike, or a city bike, higher tire pressures will correspond to a lower rolling resistance, and thus a smaller volume tire would be preferable.

One thing to note is that tire pressure makes little difference to rolling resistance at high pressures (until the pressure is low enough for the tire to be deemed flat, which is always bad). Consequently, a skinny tire will have to be pumped up less often. Factors that make more of a difference to rolling resistance are the compounds used in tire construction, tire shape and tread patterns.

Finally, in my experience, punctures are not any more likely to occur on a small volume tire. If anything, they would occur less due to the decreased footprint/contact patch. The main cause of punctures are surface conditions, such as glass shards, sharp rocks, nails and other debris. These objects are equally likely to be found on any given bike, but easier to avoid with a skinnier tyre, because the gaps between hazards are relatively larger compared to the contact patch. I believe the reason for this assumption is that high pressure tires can have much more audible and noticeable punctures, and the escaping air will do more damage to the damaged tire when pumped to 120psi than 30psi. The puncture itself is no more likely to occur in the first place.

In conclusion, city bikes that are optimised for paved, sealed roads are prime candidates to use skinny, almost race like tires and consequently reap the benefits they offer, as their daily use will almost never take the bikes outside of the optimum conditions for such a tire.


San Marco Concor -- is there a "pocket" in non-cutout version? I've read that San Marco Regale instead of having cutout implemented a relief zone (see: Regale review). So visually it is like non-cutout saddle, however something-which-works-like-a-cutout is present.

I cannot find a confirmation, that San Marco Concor (non-cutout version) also has such feature, from  technical presentation it is obvious there is some kind of "pocket" (for more foam, or for different kind of foam) exactly where the cutout comes in cutout (arrowhead) version. However what it is for?

Could someone who had such saddle in hand (personally) could confirm or deny this? I.e. the question is -- does non-cutout (non-arrowhead) version of Concor have some kind of pocket to work as some kind of cutout (relief spot)?

Usually the pocket is used as term to describe curved saddle --- but NOT here, here I use it in sense of a built-in channel, or hidden cutout.

The REGALe Carbon FX information page has an "i" button, that when clicked, loads a list of features. This includes "COREZONE", which is the feature referred to in the review you linked to.

On the Concor Carbon FX information page, I clicked on the "i" button but did not see "COREZONE" listed for any of them. If the feature isn't specifically listed, I think it's safe to assume that the relief zone is not there.

I checked a few different Concor models and didn't see "COREZONE" listed for any of them, but I didn't go through the entire list. If you're interested in a specific model, click the "i" button on its specific page to see if it's included.


How to lace a 36 hole 4x9 grouped spokes? does anybody have any information on how to lace a 36 hole 4x9 grouped spokes?

I am thinking to buy a set of rims of this make, but I am not sure how to lace it.
Can I cross the spokes or do I have to lace them straight to the hub?

Is it suitable for disc wheels?

All help highly appreciated!

I know this is an old thread but there's isn't much out there in terms of a solution for calculating spoke lengths for "quad" rims. I have a pair of hoops that are 4x8 (32h). The space between the quartets is exactly the distance that four additional holes would occupy, so it's essentially a "64h" rim in which we're skipping every other quartet of spoke holes and lacing it to a 32h hub.
Spocalc only calculates for up to 4X and DT Swiss' spoke length calculator only go up to 40 spokes. Sapim's calculates for any number of crosses and spokes.
How to measure
I think in the majority of cases people just aren't measuring correctly to begin with so they don't know what they're working with. The way to properly determine the spacing pattern is to measure on-center the distance between a quartet of four holes. Measuring it from leading edge to leading edge will give you the same distance and is easier to measure than trying to guess where the center of the hole is. Divide that by 3 to get the distance between two holes at the center. It's more accurate to measure across 4 holes and dividing by 3 over such a small distance so that you're not multiplying your measurement error. You're actually measuring the span of 3 holes, not 4.
The blank space between the quartets should be equivalent to the span of 5 holes, measured on-center between holes on either end of that blank section. Again, while there are supposed to be four holes in that space, you're actually measuring 5 holes, not 4.
To simplify, the formula is g = h ÷ 3 x 5 where g is the distance you expect the gap to be and h is the distance between 4 holes on-center. It's simple math but the concept that 4 holes across is only 3 spaces and that the gap is 5 spaces isn't entirely obvious until you think about it.

A quartet of holes measured 91.5mm on-center on the outside of my 700c rim (presumably drilled as 64h in a 4/4 pattern). 91.5mm ÷ 3 x 5 = 152.5mm. I measured the gap to be 152.0mm on-center. Close enough. The 0.5mm discrepancy was within the ±0.5mm error of my tape measure.
Even if the rim wasn't made in a 4 holes drilled, 4 holes skipped pattern, you should be able to calculate how many holes were skipped using the same method. I'm pretty certain it's almost always going to be a multiple of the space between two holes and the real and missing holes will be evenly spaced.
I did some tinkering in photoshop and it seems like those 4x9 rims were built in a 4 drilled, 3 skipped pattern. That works out to 7 x 9 = 63h. Not exactly a neat number but it's definitely a solvable lacing pattern with calculable spoke lengths.

To calculate the ERD of a rim with an odd number of holes, take the outside circumference and divide by π. In the event it's double walled, no problem, just subtract twice the distance between inner and outer wall. If those 4x9 hoops are skipping 3 holes between quads, we should be able to satisfy an equation like g = h ÷ 3 x 4.
I worked out the solution for 4x9 so if you want, you can skip down to the second section below.
4x8 laced as a 64h
Using the ÷9 method to calculate max crosses to get as close to a tangential angle for 64h, we get 7. So I mocked it up at 7X which ends up being a combination of 4X and 3X with the missing spokes.
This diagram is of one side of the wheel. Note that when you're lacing it, there will be a hole (from the other side) next to each of the real holes on this side (illustrated in red at the top of the wheel). Be sure to skip those as you normally would.
After lacing the first half of spokes from the outside-in (leading blue spokes), you flip it over and lace outside-in again with the spokes pointing the other direction (counter clockwise). The first spoke on the second side will start on the flange in the hole offset just to the left of the key spoke on the first side (#2 in the diagram) and will, likewise, run to the hole on the rim just to the left of the key spoke. It will be the first spoke in the quartet.
The holes in my rims are drilled perfectly centered, not alternatingly offset slightly as most symmetrical wheels are. If yours are, indeed, offset and your hole offsets are wrong, you'll have to move your key spoke to the right by one hole and start lacing the second side just the right of the key spoke.

Then do the inside-out trailing spokes on both sides (green). When cutting the spokes, you'll have to correct for the fact that there are no imaginary holes between the 16 actually drilled "real" holes on each side of the hub flange that the trailing green spokes use in the mockup. Conveniently, the adjacent real hole is unused since the hole on the rim that that blue leading spoke would've gone to doesn't exist.
The distance between the imaginary hole and the real one is less than 1/32 the circumference of the flange, so we'll use that as an approximation. It's a double walled rim so overshooting the spoke length by a little isn't a big deal.
The circumference is 2πr or πd where d is the diameter of the hub flange (which we already know for spoke length calculations), so we add πd ÷ 32, which in my case is π x 38mm ÷ 32 = 3.73mm. Since I'm adding, I'll round up to 4mm. If I were subtracting (which might be required in less symmetrical cases) I'd round down.

Spocalc only goes to 4-cross so I'll have to do the math manually or find another calculator. Whatever spoke length I get for each side, I'll add 4mm to half of them. I'll probably thread an extra 2mm onto those longer trailing inside-out spokes to make up for the rounding and any error so there's no chance of the spoke threads bottoming out on the nipple. I'll probably also use nipple washers since I'm expecting a little extra tension on the spokes to straighten the spokeless sections of the rim, so I'll add 1mm to the spoke lengths for that.
4x9 laced as a 63h
Now for the answer to the OP's original question. The solution I worked out for the 4x9 assumes that the rim is a 63h rim in a 4/3 (drilled/skipped) pattern laced 3X with a 36h hub.
When i was initially working it out as 4X, the corrections ended up being quite large, meaning that we would've deviated farther from a near tangential angle on half the spokes. So even though 3X also gives up a bit of angle, it's more even and overall marginally stronger.
The blue leading spokes are laced to the last hole on the right of a given quartet. Easy enough.
Every 7 "holes" (drilled and missing) on the rim and every other hole on the hub, the holes on the rim and hub line up (the purple lines). This gives us a baseline to calculate how far we're moving the trailing spokes and how much we need to fudge the spoke lengths for those spokes.
The yellow line represents where a trailing spoke would normally be when laced to a standard 36h rim. We know that it's exactly 1/18 the circumference of the rim away from the leading spokes.

We need to move the trailing spoke clockwise so that it lines up with the correct hole on the rim. We know that that hole is 2/63 away from the leading spoke, so we're moving the whole thing over by 1/42 the circumference of the rim (1/8 - 2/63 = 1/42). The new position of the trailing spoke is represented in light green.

Note that the trailing spoke doesn't line up with the hole on the hub now. It has also moved 1/42 the circumference along the hub flange. We'll use that as an approximation for how much shorter the trailing spokes needs to be.
For example, if your hub flange diameter is 48mm, that's π x 48mm ÷ 42 = 3.59mm, you'll round down to 3mm. Once you calculate your spoke lengths for each side, you'll subtract 3mm from half of the spokes on each side. If you end up with a number with a decimal that's less than 0.5, say 3.1mm, you'll probably want to round down to 2mm so that you're not short at the nipple due to the error of our approximation as well as any measurement error if you measured the rim and hub yourself. There's also going to be some error in the how accurately the spoke was cut. As with the 4x8 example, it may be a good idea to thread a few extra millimeters onto the end of the spoke, too.

When you flip it over, start lacing the hub at the hole offset just to the right of a leading spoke on the other side and run it to the hole on the rim adjacent to the other leading spoke.
If your rim holes are alternatingly offset and they're pointing the wrong way, you have to shift the leading spokes on the first side to the second hole from the right. Pay attention to this when you start with the very first spoke. If you shifted over, you'll start lacing the second side with the flange hole that's offset just to the left of the key spoke on the first side and run the spoke to the first hole on the left of the quartet adjacent to the leading spoke on the other side.
As far as disc brakes are concerned, a wheel built like this should be able to handle that torque just like any 36h 3X wheel would. If you wanted to, I'm sure you could lace it with fewer crosses if you work out the pattern and the corrections as I did. The only issue might be extreme corrections and, therefore, suboptimal spoke angles.
And there you have it! You should be able to use the same method for calculating spoke lengths for rims that group their holes into quartets in nearly any configuration, so long as the quartets are spaced by a multiple of the hole spacing.
In retrospect, I realize I could've done the 4x8 simply as 32h 3X using the same approach I used for the 4x9, but I was trying to get as many crosses as possible in order to make it a bit stronger. With 64h 7X (4X,3X) I get 4 additional crosses on each side and an ever so slightly more ideal spoke angle compared to 6X (3X). I think I would've arrived at the same correction for trailing spokes (1/32 the circumference of the hub flange). The difference would've been in the base spoke length calculation. 7X spokes are fractionally longer than 6X.


Road bike or hybrid for fitness (also including some commuting and loose gravel)? I'm new to cycling and want to start riding regularly as a form of exercise. I'm mostly going to be riding on roads/pavement but may come into contact with the occasional gravel-isn road https://upload.wikimedia.org/wikipedia/commons/1/1d/Tamsa.JPG

I may use it for commuting 1/5 times but it will mostly be for fitness.
For now I don't see myself riding long distances. I'm not sure what the distance looks like but I would expect 2 hour rides maximum (most days just 45 minutes to an hour).

I don't want a bike that's too heavy or has too many complicated gears, but I do want one that will hold up well and can accommodate the occasional change in path.

My previous bike was the cheapest I could find. It was a cruiser and barely lasted a few months when the tire popped after riding over an acorn on the road. So I want a bike where that won't happen again...

Cyclocross or gravel bike.  They both do fine on road.


Replace old square taper bottom bracket / ISO or JIS? I'm trying to replace an old worn out square taper bottom bracket from a Peugeot road bike from ca 1985. It uses english threads and the axis is 123 mm. So far so good.

But I cannot understand what type of taper (do I say it like that?) I have?
It uses a Nervar crankset and according to Sheldon Brown it should use a ISO taper.

All suggestions for what sealed bottom bracket to buy would be great.

Thanks in advance!

Update:

I bought a standard bottom bracket and it worked perfectly. It's too much snow outside to take it for a test ride but in a week or three it'll run. Thanks a lot for all help!

First, very nice drawings and measurements. This makes answering easy.

According to the Sheldon Brown link, for JIS "The standard width across the flats at the end of the axle is 12.65 mm", which is very close match to your measurement. ISO would be narrower at 12.33 mm.

Many European manufacturers switched to JIS square taper before two piece cranksets arrived, so it is not that implausible that Nervar did it too. Of course, there is the possibility that an original ISO axle was already replaced with JIS at some point. If this is the case, the end of the axle should be very deep in the crank hole.

Product recommendations are not appreciated on this site, but in my experience basic Shimano bottom brackets are fine.


What do I need to make this new fork aesthetically pleasing? I needed to replace my broken Bontrager Satellite Plus carbon/aluminum fork on my '05 Trek 1000. I chose this Q2 carbon/ aluminum fork

as a replacement because the few Satellite Plus forks I was able to find online had their steerers cut too short or were unacceptably marred for the asking price.

The unforeseen problem with this Q2 fork is that the crown seat is larger by 5 mm than the current lower headset, an Aheadset semi integrated, and therefore sticks out ridiculously past the the circumference of the lower head tube. See photo. What can be done to better mesh the new fork's crown to the head tube of the Trek?

I've been reviewing headsets and the SHIS system but I can't seem to hook up what is needed here.  Will a "conversion " crown race work? What exactly (in SHIS nomenclature) do I need if replacing the entire lower headset is the best option?  Lastly, is the crown seat diameter commonly expressed --perhaps termed something different--in the sales information of a bicycle fork? This was quite the oversight on my part having paid particular attention to steerer length, axle to crown, and the rake figures when choosing from the pool of 700c, rigid road forks.

According to Sheldon Brown, the crown seat can be milled down to proper size.  However, I could never get comfortable with the idea of tearing into that beautiful clear coat, let alone riding on a reshaped fork, so this is not an option here.

Some numbers (in the "for what it's worth" column). All are millimeters.

46.6 new fork's crown race seat diameter.
41 old fork c.r.s.
42 OD lower headtube.
37.6 OD Current  crown race  (a 30 ID) taken off the old fork.

Looking down the head tube with the new fork slipped in. Crown race not installed but current race would have no coverage beyond the current lower headset].

You are facing the as-old-as-fashion question "How can I look slimmer?", albeit on a very small scale.

Decades of empirical research and design tell us that wearing clear (possibly white) horizontal stripes color against a darker color will make the person looks like it is slimmer.

In your case, you can experiment with some matte white tape, make a ring around the fork, covering the brake mount and then paint in matte white the crown seat (the shiny, "excessive" part).

OT about the empirical knowledge on horizontal stripes: there is some peer reviewed research backing it

  Thompson, P. Mikellidou, K. (2009). The 3-D Helmholtz Square illusion:
  more reasons to wear horizontal stripes. Journal of Vision,
  9(8):50, 50a, http://journalofvision.org/9/8/50/, doi:10.1167/9.8.50


Disc brake pistons won't stay in I'm trying to replace my brake pads but when I try to push one piston in, the other one will come out and when I push it back in the previous one will do the same... how do I fix this so that both pistons remain retracted?

You need to push both pistons at the same time. There are tools for doing this, but many of us use a large flat bladed screwdriver.

You need a steady firm pressure for a few seconds to force the fuild in the lever back into the reservoir.
Have a look at this Park Tool video - about 4:10


Are thru axles enough protection for transporting a bike? I am travelling with my road bike packed inside my car in the next days. While thinking about how I will fit it in my trunk, I remembered that a lot of people put some sort of spacer in their fork/frame dropouts to prevet any damage from forces that are compressing the fork/frame when no wheels are installed.

Although this is probably more important when traveling by plane, when the bike is packed up in a container and has to sustain the harsh handling that airport luggage undergoes, I was still curious about this.

So to the actual question: Do thru axles screwed into the fork/frame without the wheels offer the same protection as special spacers made for bike transportation or is it worth getting some special equipment for this?

No - does your through-axle have shoulders to stop the bike being compressed from the side?    If it did, then the axle wouldn't go into its hole.

You're better off using a well-sized block of wood between the dropouts, and perhaps tying or taping it into place - mind out for tape adhesives on the paint/frame.  Or put a stout box over the rear mech and dropouts.


Electronic gears, how do they work? As I happen to be endowed with the honor to use a Specialized S works road bike that was lying in a friend's basement, I decided to go for a ride until swift realization of the gears being  electronic and thus not powered.
There seems to be a place to perhaps plug a battery where a bottle holder is supposed to be, perhaps one is lying around where I got the bike from.
Now, I know nothing of such advanced bicycles and tend to see how certain advancements in terms of progress may seem immediately desirable but are not so convenient as I literally can't go for a ride without electricity.
I wished to know if any of you had any further insights on this matter that I could gratefully benefit from.
May you be well!
EDIT : Thank you everyone for your helpful guidance, an avid cyclist told me which battery was fitting and I found it, Dura-ace Di2 !

There are three major component manufacturers: Shimano, SRAM, and Campagnolo. Each has their own electronic shifting system.

SRAM's is simplest to recharge: the batteries are attached directly to the front and rear derailleurs; to recharge, detach one and put it in its dedicated charging base.
Shimano has a "Di2 junction box" either underneath the stem or in one of the handlebar endcaps, which can be recharged with a USB cable.
Campagnolo has a system called EPS that is similar to Shimano's.


Anyone know what a replacement Disc pads might be for Tektro HD-R290? The brake pads say F10BS but they've been really hard to find (and unavailable on Tektro site).  Does Shimano (or anyone else) offer a resin version of this brake pad as this one is metal-ceramic?

Tektro has on their website a Brake pad finder tool.  Entering your brake model number offers several compatible brake pad models.  There are options for both resin/semi-metallic and metallic compounds.  The above linked page has itself a hyperlink to an option of buying pads direct from Tektro.
Yes, Shimano brake pads can also be used.  Your Tektro pad model numbers that can be used with the HD-R290 brakes are E10.11 & A10.11.  Shimano brake pad model numbers that can replace these are B01S and M05.  Tektro's higher performance pad option is model number P20.11 which can be switched out for Shimano's G01A, G02A, GO3S, & G04Ti.   There are a couple other Tektro pad models that can be used with the HD-R290 (see results of the pad finder), however those models aren't listed as having a like Shimano pad.


can I use an aluminium seatpost to install a tagalong on a carbon fiber frame? I've been told not to put a tagalong on my carbon bike because the carbon seat post could crack because they aren't designed to withstand the lateral tension of having the tagalong mounted there.

I'm curious if it'd be OK if I were to just mount an aluminium seat post there instead, and then mount the tagalong to the aluminium seatpost.   Will that risk the frame getting cracked knowing that the tagalong will create some extra lateral tension, or is the mouth of the seatpost hole generally strong enough to withstand a little extra weight?

This would most likely be a temporary installation, so I'm not concerned about the metal/carbon corrosion issue... only about potentially cracking my seatpost hole.

It's in the realm of things where nobody can tell you it's absolutely going to be fine, but it will probably be fine. There are some wimpy carbon frames in the world. Also it depends on how much you weigh, because as far as the frame is concerned, the forces generated by the trail-a-bike are going to be added to those generated from your seated weight. If this is a road bike and you're at around the weight limit already, it's probably not a good idea.


Cannondale Bad Boy SS conversion I'm interested in converting my Cannondale Bad Boy 2011 into a single speed bike. I found somebody who's done it on a Bad Boy 2008 (there), and somebody else who's done it one a more recent model (there).

But a bike expert told me that not every bike can be converted into SS bikes, and that most Cannondale bikes couldn't, because of the shape of the frame making it impossible to put a single speed cog (or something along these lines).

So, I'm looking for advice as to whether I can convert my BB 2011 into a single speed bike, and if so, whether there is anything different I need to do to do so.

Thank you.

I'm guessing that they were talking about replacing the rear cassette with a freewheel. However, you can convert pretty much any bike with a rear cassette to a single speed with single speed conversion kit like this one:

http://www.universalcycles.com/shopping/product_details.php?id=1764&category=2621

And a chain tensioner like this one:

http://www.universalcycles.com/shopping/product_details.php?id=47140

NB: I don't necessarily recommend either one of those products or the store that I found them on. They're just examples. You can actually even "hack" your own single speed conversion by dismantling a couple of old cassettes and using the spacers in the same way that you use the larger spacers on the ready-made conversion kit.


Mounting a dynamo headlight to a front rack I'm using B&M dynamo powered front light (an Eyc and a Cyo) on two of our bikes and currently have them mounted at the fork crown using the stock mounting brackets. This causes a large shadow from the front wheel that we both don't like. So, I'm looking for racks that have a provision for mounting a light (these lights have a 10mm wide mount that takes a bolt running perpendicular to the beam axis). Does any one have suggestions?

Typically, mini front racks have the type of mounts you are looking for. You will also likely need an arm to hold the light otherwise you will have to mount the light upside down, which the B&M is not designed to do.

A number of manufactures sell these type of racks and arms.   The racks will typically have a number of mounting points around the rack, mine happens to have five, two on each side and one in the front (which could use the same mount as the fork crown mount, but this would also expose the light more to knocks and bumps).

In the attached picture my rack is mounted quite low to the tire (so I can attach the fender to the rack), and the light is mounted low below the rack so I can fit a bag on top of the rack without interfering with the light.  As a result the pictured setup gets a slight shadow to one side.  You could mount the rack and light higher which would likely eliminate most if not all the shadow. You could also mount the arm holding the light to the front set of mounts on the rack which would move the light farther forward again eliminating a shadow.  I chose to mount in close to the rack to protect the light at the cost of a slight shadow.

Finally, my fork has an extra set of braze-ons for these types of mini-racks.  There are other types of mounting options so you don't necessarily need this braze-on to use this type of rack (e.g., via p-clamps). Some front pannier racks also have a platform like the one pictured built in, so you can use the regular mid-fork mounting point.


Need help identifying year of Ultegra rear derailleur I am helping a friend sell triathlon bike (he recently bought a mountain bike and does not need to have more bikes sitting around), and so I am trying to gather more information around the bike to provide as many details as possible to potential buyers. It's a 2009 orbea Aletta. He's got a FSA front derailleur and Shimano 105 shifters (he converted the tri bike into a roadie). According to the BBB, it does not look like the bike is worth a whole lot, but it is better than nothing!
If anyone has any clue, I would greatly appreciate it. Thanks!

I believe that is an Ultegra 6600, made from 2005 to 2008 (according to Wikipedia). Not sure you will be able to narrow it down to the exact year.


Rear wheel constant bump my rear wheel has a constant bump whenever I ride . I've done all that came to mind at firs. Deflated and checked the tire  , checked the axel for bends , checked the ball bearings , made shure the break is not rubbing and that the wheel is properly tightened on the frame .

One thing I did notice is that when I spin it in my hand I can feel the ball barings sort of lightly scratching with the axel ? I know that can be a problem for them but could that also cause that constant bump ? Any solution you have would be welcomed to check out .

Have you recently replaced a tire or tube? If so, then the tire may not be properly seated.

Remove the wheel, hold it in your lap lying flat, and rotate the wheel around looking at the edge of the rim and tire. You are looking for a "low spot" where the tire appears to "disappear" down into the wheel. It will be slight, but it doesn't take much. My old road bike has 27x1 (630x25) tires, and they can be a challenge.

If you find a "low spot", deflate the tube, put a little bit of dishwashing soap and water on the tire at the bead, and inflate the tube. You may hear a pop sound when the tire bead seats properly into the wheel.


Back gears are jumping I am a newbie at gears.  I had to buy a new cassette and back wheel, and have just done a straight swap.

Now I am not getting all my gears at the back. Eg when in fifth gear it says I'm in 4th etc.

What is wrong ?

When you replace a wheel the cassette is not guaranteed to be in exactly the same place relative to the frame as it was on the old wheel, so you need to re-adjust the limits and indexing of the derailleur. Park Tool has a great instruction page with videos that use can use to learn how to do this.

Also make sure that you cassette is installed properly. Some cassettes have a spacer that must be installed on the freehub before the cassette sprockets.

As Criggie said in a comment, you should replace the chain when you replace the cassette.


Sunglasses fogging on cool bright mornings - can I improve airflow? My favourite riding sunglasses are my Bollé Mamba II safety sunglasses - they're light and wrap around properly while being by far the most  comfortable ones I've found.  They're also cheap.

There is a downside, which is normally only apparent in winter but was a bit of an issue yesterday morning: they fog easily, especially on the bit I look through using the drops or aero bars.  Yesterday was sunny all day, but I started before it warmed up, so I was out in around 10°C, sweating a little.  It's possible wind chill on the outside was cooling the glasses, as I averaged >30km/h for the hour or two this was a problem, before the day warmed up.  This wasn't about stopping, because I didn't, but when rolling along.  It was better when riding into the sun, but that never lasted long.

I like the way they sit so close to my face, but it means that unlike my less-good cycling-specific glasses there's no airflow behind the lens.

The issue may be what they call "upper protection".  They're a sort of frameless design, but with a little ridge running along the top of the lens, at eyebrow height and touching my face.  It's visible (just) in this photo of them upside down:

They're getting a little scratched and it's nearly time for a new pair, so it's a  good time to try some experiments.  Is there some way I can increase the airflow behind the lens? Are there designs that do this so I can be inspired?  I don't really want to try a coating, because I'm likely to wipe it off.

Other, looser fitting and less comfortable glasses don't fog up nearly as much (including another Bollé polycarbonate pair, so it's not the material).

The problem with fogging up glasses lies with the shape of the glasses AND the shape of the rider's head. Some combinations are simply incompatible.

Since you can't change your head, try with a different pair of glasses. Also, some glasses have small ventilation holes at the top of the screen. Or you might get replacement screens that have these.


Help in Identifying bicycle from Mozart in the Jungle Show? Can anyone identify this bicycle manufacturer? Bike appears in season 1 of Mozart in the Jungle - the Amazon show

Edit - more shots of the bike (SE doesn't like mp4)

https://i.imgur.com/lIKedCz.mp4

https://i.imgur.com/6iCxtkk.mp4

It's Tokyobike. You are welcome.

https://www.tokyobikenyc.com/


Which gears not to use in a 2 X 9 gear bike I am new to biking. I bought a hybrid bike with 9 gears at the back tire and 2 gears at the front. For reference lets say gears at front (chain ring) are numbered 1-2 and gears at back are numbered 1-9. As the numbers increase the the cycle becomes harder to pedal (for both front and back). For example if you switch from 1 to 2 at front cycle is harder to pedal. And if you switch from 2 to 3 at back tire, the cycle is harder to pedal.

Now my question is this. Are there certain gear combinations, I should not be using. Can you write those combinations down for me like (1 back, 5 front). So I can use that for reference. The particular problem I am having is that when I am at around 7-9 at back and 1 or 2 at front the cycle starts making a weird noise. Is it normal? Any other combination I should not use?

The general rule is that you don't want the chain angle to be extreme (i.e. the chain should be running as parallel to the frame as possible) - when the chain is at an extreme angle, it is called cross chaining. This is a good read.

For example, you don't want to use the little ring in the front and the little cog in the back (this increases wear on both of them). Likewise, if you want to use the big ring in the front and big ring in the back, you may want to go to the middle ring in the front instead and remain near the center in the rear (if you had it -- for a double in the front, there will be a point where you'll prefer to shift down in the front and then stay near the middle of the cassette).

The most important thing to do is to avoid small-small combination though - modern drivetrains aren't too unhappy with cross chaining, but its still not good practice.

Also, note that the gears you use at the time depend on the terrain and what not -- try to aim for a cadence of about 70-90 RPM (how fast the pedals turn).


Why are folding bike warranties so short? I am looking for an affordable  folding bike with reliable warranty.  So far all the bikes I looked at have 2 weeks to 3 months warranty for frame and manufacturers warranty for parts, nothing like 5 years to 10 years warranty for their fixed frame counterparts. Why are folding bike warranties so short?

Sounds like you're looking for opposing features.  A good/great folding bike will cost more than the equivalent full-sized bike.

A cheap folding bike will have the bare minimum warranty permitted in your location.

For example, the warranty on a Giant bike is

  LIMITED WARRANTY
  Giant warrants for the original owner only the frame, rigid fork, or original component parts of each new Giant brand bicycle to be free from defects in material and workmanship for the following specified periods:
  Warranty of lifetime for - The bicycle frame, except on models intended for downhill purposes.
  Warranty of ten years for -  Rigid forks.
  Warranty of three years for - Frames on models intended for downhill purposes.
  Warranty of one year for - Paint finish and decals
  All other original parts, including rear shock linkages, but excluding non Giant Brand parts, suspension forks and rear shock absorbers. (All non Giant brand parts, suspension forks, and rear shock absorbers shall be covered exclusively by the stated warranty of their original manufacturer.)

Their only folder is $819 NZ or about $600 USD.

By comparison a top folder like a brompton has a 5 year warranty on the frame, and only on material and manufacturing faults.  This will not cover accident damage or wear and tear.

  If your bicycle has a material or manufacturing defect, we will replace the defective part free of charge if we are notified within five years (in the case of a frame part) or two years (in the case of other parts) from the date of first purchase of the bicycle.

Their folders range from £800 to £2200, so $1100 to $3000 USD.

In short, you get the warranty you pay for.


What brand of bicycle is this? Looking for the brand of this bike - like the style and color. Only have the photo

A google reverse image search tells me it's a Martone Sweetzer (US) or Real (European version).

http://www.martonecycling.eu/product-EU-5-25-Womens_Real

From certain features of the frame (the bend in the top tube etc.) I'd say that's the same bike, but that your picture is of a slightly customised version with a different saddle and grips.


Best way to strengthen a wheel? I'm a relatively heavy chap - 95kg or so. (15 stone, 210 pounds)  I've got a commuter bike which uses a NuVinci N360 hub.  The hub itself is quite heavy at 2.5kg and I suspect contributes to what is already a heavily loaded wheel due to my weight.  The wheel itself is a 700c 28 with 32 spokes.  All in with bike, padlock and commuter luggage rack and bag I get to about 115kg.

I built a wheel myself for the first time about 4 months ago using 14G double butted Halo spokes.  The large size of the hub doesn't allow for anything more than 2 cross which is I what I did.  I did not use a spoke tension gauge as it seemed expensive at the time and I was hoping not to build wheels too many times.  The wheel was pretty true at the build and I thought I did an OK to good job.  but who really knows without a tension gauge.

The wheel was fine for about 4 months, doing 12 road miles a day, but has now started popping spokes - about 1 or 2 a week and clearly needs a rebuild.  All the spokes have gone at the elbow - right where it attaches to the hub.  No sign of nipples pulling through the rim, which isn't eyeletted.  There are obviously quite a few parameters in the above which are not optimised for weight (28 tyre; 32 holes; 14G spokes; amateur wheelbuilder etc).  I quite like the belt driven continuously variable transmission for commuting (scratch that, I love it) and so unfortunately the hub and the 32h is something I have to live with.  But of the below parameters, how would you prioritise them in order to arrive at something that doesn't pop spokes long term?  Really I guess I'm asking if my problem is more due to system spec or system build quality.

Use 12G or 13G spokes.  Or maybe triple butted 14G is better?
Put a bigger tyre on to reduce peak loading
Buy a spoke gauge when doing the next build
Get a professional wheelbuilder to do it
Get an eyeletted rim which allows more tension
Anything else you might think of?

Ideally I'd also like to get my son on the back which would add another 15-20kg by the time you pay for the seat.  Is it realistic for me to do that without going on a severe diet?

Thanks advance for your thoughts.

EDIT:  Added a few more details

When the spokes break, do they snap at the J bend?  Or elsewhere?

If the little mushroomed cap is gone at the hub end and there's a spikey "claw" then your spoke tension is low which is stressing then tensionining the spokes on every wheel revolution.

I'd start by lightly tapping the wheel spokes with a screwdriver, key, or something light.  And then compare that TINK sound with other bike wheels.
Or if you're a hands-on person then gently squeeze two spokes somewhere outboard of where they cross.  Compare that hand-feel with other people's bikes of similar wheel size and construction.

I think you could probably tighten every spoke nipple by a half turn or even a full turn all round.  Be aware that a weak spoke might choose this time to let-go.

If you don't feel up to all the messing around, there's no shame in taking the wheel to a LBS for a professional build.  A good wheel is the ultimate outcome here.

Do you know what pattern its laced with?  Radial spoking is rarely if ever done on the back wheel, so you're likely to have some cross pattern.   2-cross or 3-cross are most likely.  If you have a 1-cross then the spokes don't leave the hub at a great angle, and are not far off radial, so this stresses the spoke's J bend more than 2/3/4 cross.

No idea how large the nuvinci hub is, but I've put an alfine11 in a 26" wheel and had to go 2 cross.   I guess you'd be best with 3-cross on a 700c (29") wheel.

Thicker spokes is always an option too, but if you do this then the whole wheel needs relacing.  I wouldn't mix gauges on the same side, though I might accept having a different gauge on the left vs the right.

I'd probably go with straight spokes.  The cost of butted, double and triple aren't worth it, they're more for weight saving than adding strength.  Butted spokes have a thinner piece in the middle which can stretch a little more under impact, leading to a "better" ride.

Aside, 95 kilograms is not ridiculously heavy - I was there only 6 months ago.
 Sure we're more than a GCN rider in their 60s and 70s, but more mass means more muscle, right ?

You might not be good on a svelt road bike but I'm guessing you're on a rigid commuter/hybrid bike.   Your weight is not the root problem here, though it will make potholes much harder on your bike, and brakes will wear a little faster.  On the upside, more weight means more exercise per metre travelled.

The hub is probably not really helping, given its a lot of weight compared to a 100 gram hub and a 400 gram cassette etc.  The hub's position means it has the least "suspension" effect and can make the wheel harsher.  If your bike has rear suspension, the hub is still unsuspended weight and that contributes to the impacts, stressing those spokes.

Basically don't ride off kerbs/curbs and don't bulldoze your way through potholes or speedbumps.  Learn to unweight your saddle, then "ballerina" your bike as it passes over the obstacle, effectively halving the weight for an instant.  You're not trying to get air or off the ground, just unweight for a brief instant.  Timing is everything and cleats can help a lot.

The eyeletted rim is only relevant if you're causing damage to the rim.  If the nipples are pulling through the rim holes then you would benefit from eyelets.  I doubt this is required in your case.

A bigger tyre would be great if you can fit it in the frame.  I rode 23mm for a while, then went 28mm and then 32 for a short while  Each step was an improvement in comfort, but other changes meant I had to return to a 25mm on the current road bike.

The pinch points are your chainstays, seat stays, and rim brake bridge or calipers if you have them.  Sometimes mudguards can be limiting too, but they're easier to adjust than the frame.


The shifters and brakes are one piece I found this old junkie bike and I want to use it. I don't have very much experience with bikes, and I noticed that that the speed shifters and the brake handles are one piece together. Is that normal? Do they normally come as one piece?

Because I was thinking of getting new brake handles but I don't want to change the shifters.

That is pretty normal on entry-level mountain bikes. Shimano claims this is to not confuse beginners.

Torney, Altus, Acera and Alivio groupsets come this way, at least by default.

However, Acera and Alivio are getting better and better with the trickle-down tecknowogy.

See here, in the upper corner "Components".


Can I reuse an old rim to build a new wheel? So, theoretically, can I strip an old rear 700c wheel of its rim and then use same (aluminum) rim to build a wheel with a different hub and different spokes? I'm aware that stressed aluminum is dangerous, but I wonder if one can get away with it.

Any advice appreciated.

Yes, absolutely, and it can make plenty of sense sometimes. Hubs failing early is one case. It has also become more frequent, although maybe not common, for people to want to swap carbon rims around, especially on disc brake wheels, because they have so much invested in the rim, and they can go a long time. I've rebuilt a handful of carbon rims in recent years for people playing with different hubs who wanted to keep their big dollar rims.

When you unlace the old rim, you want to do so in a fairly gentle, gradual way, especially at first when the spoke tension is still high. It's not good for rims of any material to be bent around unnecessarily, which is what happens if all the tension gets released at once on a spoke while the others are still tensioned. In other words, cutting the hub out like one does to re-lace a hub is not what you want to do here. What I do is go around doing detensioning layers of a half turn per spoke until I have quite low tension, then go to full turns. As soon as the spokes are sloppy loose, there's no tension and you can cut them or use a nipple driver in reverse from there.

Once you have your bare rim, it's a good idea if possible to check what kind of shape it's in without being acted upon by spoke tension. I always do this by taking a good quality new machined sidewall rim of the same size, laying it on the bench or ground, and laying the rim to be reused on top of that. You're essentially making a surface table out of the new rim, and it works well. Any lateral kinks or distortions will reveal themselves easily. Major radial dips or rises can be felt for this way too, but it's more subtle. If there are any radial distortions, the old rim probably isn't worth messing with. If you find lateral waviness inside of 2mm total gap or so it's probably fine; it will create some amount of tension imbalance, but only on the order of a couple quarter turn adjustments.

As far as fatigue, if you're gentle with taking the old wheel apart, there's not much difference between reusing the rim and continuing to ride the old wheel.


Where to get new front brake release for Fuji Sports 12 Any suggestions for where I can buy a new front brake release for my Fuji Sports 12 bicycle?  What is the part formally called so I can search for it?

Remove the part altogether and replace it with a brake cable stop such as this one
found at http://sheldonbrown.com/harris/images/brh27.jpg

and insert a release such as this one

found at http://bicyclehabitat.com/images/library/large/shimano_sm_cb90_1_13_z.jpg


Campagnolo cabling: can I use other non-Campagnolo brands? The obvious reason why, is cost!

I need my front derailuer's cable to be replaced and I'd like to simply buy some raw brake cable from the bike shop and simply re-insert into my existing campy cable guides. Can that be done, or do I have to buy Campagnolo cables? Is there a cable guide or some PDF that has more technical details specific to Campagnolo cables?

I have Athena 11sp with 11sp Campagnolo Record shifters - not EPS.

Thanks

You don't have to buy Campy brand cables, but you do have to buy Campy-compatible cables, because they use a head that's a little bit smaller for both shift and brake cables. If you ignore this, it can seem like it's fine, but get stuck in your lever. The alternative in a pinch is taking a little off with a grinder or file.

Most shops will have individual carded Campy-compatible cables that are more expensive than bulk but not nearly as much as Campy. Some shops have them in bulk. There is no compatibility issue with using them in your Campy housings.


Product selection help: wheelset for vintage(ish)steel roadbike I have an 80's vintage Peugeot steel frame that I'm gradually trying to upgrade.

I'm thinking about improving the wheels and originally thought a set of Mavic Aksiums would be a nice upgrade. Problem is, it's not really the right era of component for such a bike, although I think compatibility shouldn't be too much problem...

I have also considered getting a set of wheels built that might look a bit more at home on the bike - Mavic Open Pros on a Shimano hub - (600 tricolours if I can get hold of some, modern 105s if not - they are just silver and quite plain looking so shouldn't ruin the look too much). Trouble is the second option is looking like minimum £230 for the set while the Aksiums can be have for £140.

My question is what would you recommend? Is the performance difference between the 2 options significant (not that this is ever going to be a competitive bike!)

Current wheels are a crappy £30 shimano road wheel on the back (original died) and the original maillard hub wheel on the front (which is actually pretty light but has a poor braking surface)

Why not keep a look out for some Mailard, Mavic or similar wheels from the early 80's on ebay. Should be much cheaper and fit with the frame more happily. With the cash you'll save you can get some quality brake pads that are designed to work on those steel rims.


Trainer bike tire does not go on nicely, am I doing something wrong? I got a used trainer and trainer tire off of Fb marketplace.

I installed the tire, pumped it to to the recommended 100 PSI and I noticed a bulge. I thought l had installed it incorrectly so I removed it and reinstalled again.

Here’s a picture of the worse case during my multiple attempts.

I noticed that it was always around the valve.

Eventually, I was able to install it, but there was still a little bit of a bulge. At least the inner tube was not popping out.

My approach was basically to install the tire, pump it up a little bit, adjusted the tire to make sure that it’s sitting well. Pumped it up some more and repeated.

Is there a special way to install these trainer tires? Was I just doing it incorrectly? The fact that it was always around the valve seemed like it’s a clue that maybe I didn’t seat the tire correctly around the valve.

Make sure you are fitting the tire correctly. Examine the bread all the way around the rim on both sides and make sure it is seated evenly.

I wonder if the inner tube is not properly inside the tire near the valve. The reinforced area around the valve can get stuck under the tire bead. Before inflating, push the valve into the rim to make sure the tube is properly inside the tire.

If you still have problems try marking the tire where it popped off the rim and mounting the it rotated 180 degrees around the rim. If it comes off the bead in the same place the issue may be damage to you rim that the loose fitting tire is revealing. If the same section of tire pops off the tire bead may be damaged at that point.


Looking for lightweight somewhat inexpensive flatmount brake calipers for a road bike shipped from North America Looking for the right brake calipers. I see a lot shipped from China or those that cost $130+ for 2.
I need:
disc brakes
cable pull or cable to hydraulic conversion as I am not switching out my ultegra levers.
Flat mount
Short Pull/road bike
Lightweight @ 140 grams or so each
I see a lot of these at crazy high prices or shipping from China but I need this in about 1 1/2 weeks so I cant wait that long.

If you can't wait for shipping, then your only option is to go to your local bike shops and see what's in stock now.
Brakes are important - I'd suggest politely not focusing primarily on the price, and instead prioritise compatibility, function, and availibility over appearance/price.
Your other option is to shop on your local auction websites, whether that be ebay or craiglist or gumtree, etc.
And try to have a a backup plan too, in case your primary plan doesn't work.


Mix Shimano Deore derailleurs with Microshift shifter for Shimano I have Shimano Deore derailleurs 3x8 and I am thinking about upgrading my system with a combined shifter/brake system, such as Microshift's SB-R483. Microshift themeselves states that this system is only compatible with Shimano Claris 8 speed 2403,2303,3303 derailleur system.

However, half ignoring their statement, could it be possible to use the SB-R483-system for a Shimano Deore derailleur? Doesn't Shimano have an internal standard for the derailleur system so that a Shimano compatible 3x8 shifter fits any Shimano 3x8 derailleur system. Any experience or superb technical knowledge?

The stumbling block is that while Shimano mountain and road rear derailers used the same actuation ratio and were fully cross-compatible until the start of 10spd mountain, the front derailers have always used a different cable pull. So if you have a mountain FD as well, you'll probably find it's impossible to get the front shifting set up for no chain rub anywhere, and shifting performance won't be very good. There are many questions here that explore options in this scenario.


Figures on accidents involving cyclists where motorists are using cell/mobile phones I am trying to get hold of some figures for accident rates where either, ideally just cyclists or, just general road users & pedestrians, are involved in accidents (or reported near misses) because a motorist/cyclist has been using a mobile phone. I would like (if possible) to have information regarding Sweden and other countries where cell phone use is not banned, and in countries where it has been banned such as the UK.

As a cyclist who lived in the UK and now lives in Sweden I notice a considerable difference in my "near miss" rate, and the vast majority of my near misses here come from phone users (and bus drivers, but that was the same in GB!). If I can get some statistics I am going to look in to campaigning my local politician and having cycling friends in the area note down their near miss rates (how many kilometers per evasive action).

Examples of the sort of nice stats I'm looking for:

xx% of accidents involving cyclists in Sweden are suspected or proven to be due to one or more parties involved using a cell phone at the time of the accident.

Since banning the use of cell phones the overall rate of accidents involving cyclists has decreased by xx% in the UK, and those involving cell phones has decreased from aa% to bb%

As Batman has commented, I suspect getting the data down to this level is probably going to be quite hard.  That said there is some Australian research which may be of interest to you.  In particular a study undertaken in South Australia which looked at the circumstances surrounding crash involvement for a group of 61 bicycle riders involved in a collision with a motorised vehicle who were admitted to the Royal Adelaide Hospital over the period between January 1 2008 and December 31 2010. You can read a summary of this study on my site.

This descriptive study provides some insight into cyclists and motor vehicle interaction and adds to growing literature on the subject.

http://aushiker.com/profiling-cyclists-injured-in-crashes/


Shimano Deore XT: is 9-speed no longer continued? (Europe) For an upgrade I'm trying to decide whether to change to 9-speed or 10-speed cassette, chain, derailleur, shifter and crank.

On the european Shimano website there are not many words about 9-speed components in the Deore XT Group and a european reseller has marked many items as "discontinued".

When choosing 9-speed today will I probably have trouble finding new components in about five years? Has Shimano officially discontinued 9-speed?

Shimano has a pretty good track record of wear parts availability for older groupsets. I am using 8-speed myself, and there are several European mail order stores as well as local shops that have spare cassettes and chains.  I would expect that 9-speed spare parts aren't going away either.

The problem with off-road groups is that rear derailleurs are not compatible between 9- and 10-speed, so you need to change shifters, derailleurs, cassette and chain if you need to switch later.

EDIT: To clarify, even though 9-speed XT groups have not been sold in a while, XT-level 9-speed wear parts are still available. For 8-speed it looks like spares above Deore/Tiagra level are no longer available.


Is it possible to ride 18km everyday for a beginner? I decided to ride to my university which is 9km away from my home and it is placed on a foothill. I guess the route is 5degrees uphill steep.

I have ridden short routes before but not as long as 18 km.. I'm a beginner in riding, but physically I'm partly OK.

EDIT:
This is the path's elevation profile from google earth:
The average slope is 4.6% and max slope is 13.1% and altitude is 1224 ft.

18km a day is not far, as long as you have an OK fitness level to start with and no health issues, it is certainly achievable, but...

You will not get any rest days. I was once told, you do not get fit exercising, you get fit recovering. If you ride 5 days a week, there's no recovery time. This could lead to problems since each day's effort is stressing your body. For the beginning I would strongly recommend not more than 3 days (with a day between) until you are sure you can comfortably do five days every week.

What I would suggest you to do is first thing in the morning measure your resting pulse rate. Do this for 3 or 4 mornings to establish a baseline. Start riding, taking it easy to begin with (for the first couple of weeks). Note how you feel and your resting pulse rate - if you feel bad and your pulse is higher than it should be, have a rest day or two. (Note - normally your resting pulse rate will fall as you get fitter, so your baseline will change.)

The trick is to have an alternative to riding available so you don't need to ride if you need a rest, but not so available that you use it all the time.


Aero spokes strength on a family bicycle I am building a new wheel for my family bike: there will be a kid seat on the back rack over the wheel. I picked up some cheap double butted flat aero spokes (not elliptical but flat).
From reading around forums these should be no different to a standard round spoke.

My question is this: is the double butted flat spoke weaker regarding the situation, not road/race but weight carrying?

Safety is important. No I am not looking for speed I got them as they were cheap clearance (Pro-Lite Gavia Aero Spokes).

I don't think you'll have a problem. Aero spokes are no less strong than regular double butted spokes. I use them for downhill riding and whenever one breaks (due to bad handling, loose spokes or extreme impacts) it is never on the bladed flat area. They'll either break close to the nipple or close to the spoke head.

Also note that usually spokes break one by one and never all together. So even in the rare scenario that one breaks (probably because they where too loose) the wheel will be able to continue riding normally and you'll replace it and retighten as soon as you can.


How to identify whether a TRP Spyre mechanical disc brake is the post-recall version? For online (bargain) shoppers who face the risk of possibly buying old stock, are there any markings on the post-recall TRP Spyre that could be used to clearly identify it as the new version?

From the article
"Recalled calipers have a fastening screw with a hollow six-pointed star-shaped head with no markings on it and a 3 millimeter pad adjustment screw on the outward side."
Modern TRP SPyre calipers have one 3 millimeter pad adjustment screw on both sides and no star-shaped head.
From your article:

From modern shops:


Disc brake mount/adapter bolt length My bike's frameset has IS mounts. The mounts are 9.6mm thick. I bought a pair of IS to post mount adapters but they don't come with bolts. The adapters are 11mm thick. How long should the bolts be?
The adapters I bought are not Shimano but I saw that Shimano adapters (SM-MA-F180P/S, SM-MA-R160P/S) come with bolts 18.7mm long. Now I'm not sure how thick their adapters are. Are the bolts supposed to thread past the adapter or just short of it? Shimano also has those snap rings; are those needed or just the bolts and washers?

These bolts are usually 18-20mm long M6 bolts. The exact length isn’t important, but going shorter than 15 will likely mean insufficient thread engagement, while longer than 24 or so could potentially result in the bolt interfering with the rotor.
The plastic snap rings aren’t strictly necessary. They act as a second line of defense against the bolts inadvertently loosening. Shimano includes many of these secondary safety systems with their products (eg. safety clips on brake pad retaining bolts, threadlocker, fancy spring washers under rotor bolts, and these plastic things) which certainly will help, but the bike won’t explode if you don’t use them.