4 year old alivio 8 speed rear gears - compatible chain I need to replace my chain (for the first time).  My bike is roughly 4 years old using Alivio 8 speed (24 gears) system.  Looking at wiggle they seem to have 3 chains available.

Looking at other questions on here, (for example Are all 9 speed chains compatible with all 9 speed systems?) it would seem that any 8 speed should work.

I would like to ask is there a good reason to go for one or another (they all roughly the same price, within a few pounds).

http://www.wiggle.co.uk/?s=shimano+8%20speed%20chain

No, all 8 speed chains are not compatible. For that matter, neither are all 9 speed chains. But for practical purposes, they will be within tolerance to work well enough. Ideal shifting is best obtained with all components being of the same design, in good condition, and good adjustment.

The chains you linked to: There are 2 types of Shimano 8 speed chains. The common one, HG or Hyperglide and IG, or Interglide chains, which are not designed to work together.

If you have HG, and buy a shimano chain, you should get an HG chain.

SRAM chains have looser tolerances, so any 7/8 speed chain will do as well as any other.

I am not saying you can't use any 8 speed chain. Only that some will shift better than others.


Clear lacquer on steel frame I'm currently working on a steel frame that I got off ebay. I'm removing the existing paint using wire brush adapters for a drill (didn't want to get involved in nasty chemical baths). One result of this is that it gives a nice "brushed" effect, which I thought would look quite nice unpainted.

Would a clear lacquer, such as this one, be sufficient to keep rust at bay?

The manufacturer recommends this product for protecting a painted surface and not used on bare metal. Lacquer by its nature (at least the types still available in the U.S.) provides a beautiful finish but not very good at chip resistance. It is typically applied in multiple layers with sanding between coats. Take this to mean very time consuming and tedious. I would look for a product designed for bare metal, a urethane or clear epoxy should be much more durable than a lacquer. I would suggest finding an old bike or scrap pipe and practice your technique particularly in the headset and bottom bracket area. If you took the frame apart, tape all the threaded areas to keep the clear out of the threaded parts.


Is slop in the headtube normal? I have a carbon Fibre front fork "BSC profile design" and when I tighten up all the screws on it snugly there is no movement (forward backward) but I go out for a ride and by the end there is a small amount of slop in it (like when pressing the front brake the fork slides back a few mil before hitting the back of the headtube) is this normal? Or is there something I need to do to reduce the slop?

That's not normal - any knock is also going to accelerate wear so you must fix it soon.

Did you loosen the stem bolts before tightening down the headclamp?
See [1].  The tightening order is the same for all materials, but the torques are vastly different. The torque range is usually 4-8 Nm for the head clamp for carbon forks, similar for stem clamps. You can use a special carbon grease to increase friction to that you succeed at low torques.  See [2]

Does it have a couple of years or more of wear on it?  Head clamps wear out.  Head clamps for carbon frames are remarkably skimpy things.

[1] http://www.artscyclery.com/learningcenter/tightenyourheadset.html

[2] Attaching a stem to a carbon steerer: how much torque?


Are dynamo hubs specific to particular lights? I am looking to purchase a dynamo hub, such as those made by Shimano, Son, Exposure etc. and a set of lights to connect to it.
What I want to know is if any dynamo light will work with any dynamo hub, if they have proprietary connectors or if there are connector standards that work together?
If not, are adapters available between the various brands?

Here is a picture of the connectors on a Son hub, which are not a standard I am familiar with.

Speaking in terms of past few decades to current generator hubs and lights, mostly they are interchangeable, with some qualifiers and exceptions.
Almost all current hubs and lights are based around 6 volt, 3 watt, and can all work together. Usually the deal is your hub is going to have its own connector type which it will probably come with, like the two-piece plastic plugs for Shimano or the spade connectors for Schmidt. Your light will either have an integral wire as in recent higher end B&M and Schmidt lights, or terminals for a wire with spade connectors, or in some cases a proprietary plug type with an included wire. It's going to be some type of two-strand wire regardless, which you'll then cut to length, prep as needed and connect to whatever kind of connector(s) the hub takes. Most lights come with wire but not all, and in some cases you'll have choices like getting the fancy Schmidt coax wire, which is excellent but a little more involved to prep.
There are some oddball 12v6w lights and hubs that won't play nice with others, and then there are some random things like the old Schmidt E6Z secondary light that would probably need some creative splicing to work with a Shimano plug, and there's probably some other miscellaneous exceptions. But the reason they're exceptional is that almost all of these lights are intended to be usable as upgrades or replacements on random bikes in the generator countries, and same deal with hubs being intended to drop in on existing bikes, so they're mostly very much intended to be cross-compatible.


Why should the front wheel be more heavily loaded when touring? Possible Duplicate:
  Touring load weight distribution

In reading advice for carrying cargo on a bicycle, whether for touring or otherwise, I see recommendations (such as here) that load should be either evenly distributed between the front and rear wheels, or slightly greater, 60/40, on the front wheel.

Why is this? My intuition says that more load should be on the rear wheel, but my touring experience is limited.

Bonus points for answers with actual physics in them.

When you sit on your bike, you put more weight on the rear wheel than the front (it's easy to use bathroom scales to see exactly how much). By distributing your cargo 60/40 to the front, you get a more even distribution of overall weight on the tires. This is good for several reasons. The tires (assuming same size) have the same load bearing ability, so having them evenly balanced is better - particularly on a heavily laden tourer. Also if you put to much weight to far back, there is no weight to hold the front down. This negatively affects cornering, inducing uncontrollable under steer, and also affects hill climbing. A tourer usually has an insanely low granny gear, which means it's possible to grind up very steep hills, provided the torque does not lift the front wheel. Pulling wheelies on a fully loaded tourer is something best avoided by all but the most skilled riders.

These are only guidelines. Every rider and bike is different, so you should do what suits you. Don't be scared to experiment - even once you find a way to load that you like. If you don't try something different, you may never find that "better" way...

Forgive me, I will go for the bonus points.

Max Torque induced by Pedal
   Force on Chain =
      (Rider Weight * Crank Length) / Small Chainring Diameter.

Torque on back wheel =
       (Force on Chain * Diameter of Largest Cassette gear ) / Wheel Diameter

Torque to rotate bike  =
       Wheel base * Weight on Front wheel.

Crash ===    Torque to rotate bike > Torque on back wheel


Is 160mm crank too short for me? I’ve done some research about crank length. When I’m riding full-gas my knee is starting to hurt but when I’m just chilling in group rides I feel alright.
My crank length at the moment is 172.5mm and I’m thinking upgrading to a shorter crankset. My inseam is 30 inches (762mm) and by the formula I found on the internet by GCN, I should have a 160mm crank length.
Is 160mm too short or should I just go buy the 165mm?

160mm crank is abnormally short. This doesn't mean that you shouldn't but as Axemasta mentions, you should have a bike fit before deciding what crank arm length you should have. Plus you've not given any details about your bike or it's size.

There are so many variables involved in knee pain, it would be foolish for anyone to suggest your first course of action to be crank arm length.

Bikes related variables for knee pain:

Overall wrong size frame
Bad saddle position (tilt and position on rail)
Stem too long
Handle tilt
Crank length
Pedal choice / fit

Body related variables for knee pain:

Incorrect cycling technique
Muscle imbalance
Muscle tightness
Non-optimal nutrition

These are just examples of a much larger list.

So, in my opinion, without finding the root cause of your issue, buying extremely short cranks should only be done if you are 100% that is what you need. And I don't think (with the information you have given) that will be what you need.


How (un)safe is it to ride barefoot? Sometimes I use bike for a week long trip camping along, doing maybe 200km per day riding on asphalt road. In the end, my feet have bad smell, which is not super strange or concerning, but it does seem a bit unhygienical to do so, especially if I don't have an opportunity to take a shower, I have a feeling I might get some feet fungus.

I tried riding barefoot once for short time and everything went well. I don't have sensitive feet and my pedals are mostly flat, so it's not a pain to pedal.

Now, I've almost never seen anybody else doing it so there must be a downside or danger to it? Does anyone have any experience on this?

It may well become uncomfortable after pedalling for some time, so don't rely on a quick test ride to check.

More importantly though, you need to be able to stop the bike based on the need to stop, and put your foot down without examining the ground for broken glass, thorns etc. It's not completely unknown to strike the sole of your shoe on the ground, like pedal strike, and this would hurt quite badly in bare feet (there's one roundabout I've done this several times, due to a combination of the camber, turning onto a hill, and having to pull away fast because of a poor line of sight). If you ever bump your foot on your front wheel turning at low speed, that could become unpleasant too.

Let's face it, all cyclists get stinky shoes and feet . And a bad smell doesn't mean a fungal infection. Letting your feet and preferably shoes dry out at the end of each day is a big help. That's the time to go barefoot


What is a substitute inner tube for 27x2.125" tyres (in Prague)? I'm on an extended bike tour on an... unusual... bicycle, and I've run out of spares. DECATHLON in the Czech Republic doesn't seem to sell tubes in my size (I've tried 3 already), and I don't have time to go crawling through every bike shop in the city hunting for them or to have them ordered in.
Is there anyway in Prague where I can buy any size of tubes that fit these tyres off the shelf? Valve type doesn't matter.
What tubes are a suitable substitute?

Tl;dr: use 700c or 29"
27x2.125" is very rare.  27x2⅛" would be more likely, and wouldn't quite be the same thing, but for tubes the answer would be the same.  Generally though, 27" tyres are narrower than this, up to about 40mm or 1 1/2"
Schwalbe says that for 27" tubes you should use 700c, which are very common.  The bead seat diameter of 700c is 622mm; for most 27" sizes it's 630mm.  As your tyres are on the wide side, you'd want to use 29x2.1" (as 29" is a marketing name for wide 700c)
Tubes are really rather forgiving.  Examples: I'm currently running a 26" tube in one wheel of my 29er hardtail (a pain to fit, but I'd taken the wrong tube with me and had to get home); I've replaced a tube with a puncture only to find that I'd been riding one old bike for a year on a 26" tyre with a 24" tube.
Note that the width is also given as a range, so one tube might be suitable for 1.5-2.4" widths.  Schwalbe's SV19 is a common example tube, and is specified as suitable for ETRTO diameters from 584mm (27.5") to 635mm (28x1 1/2"/700B) and widths from 40-62mm.  I wouldn't choose it for the very largest diameter and width specified, but it would work.
For info, tyre sizing systems are bizarre - 1/4 is not the same as 0.25 for sizes in inches, and 29"=28", while 27">27.5" (and can be bigger than 29").


Terminology index - a list of bike part names and cycling concepts This question and its answers list the names of bike parts and cycling concepts.
Some Rules

Make sure you only put one term per answer!
Try to include an image if applicable
Include sources that contain detailed information
Add a link to the index in this question using edit.

Also, I made this a community wiki, so that anyone will be able to edit it, and to stop rep-hoarding

There's a handy reference at the Park Tool Co. website, a bike repair map; it's a diagram of a bike with all the parts labeled, and is very handy! At the moment, the diagram is up at parktool.com/blog/repair-help. (They've changed the URL in the past, so this link may break.)
A road bike has the following parts (source):

A mountain bike has the following parts (source):

Edit: This page is meant to identify what things or concepts are (as per this thread in meta). If you want to recommend an accessory or a specific product you've found handy, please use the accessories page.

Contents

Axle
Axle Nuts

BCD (Bolt Circle Diameter)BearingBonk/BonkingBottle Cage / Bottle HolderBottom Bracket
Boom/Boom TubeBrazed FrameBrifterBSD (Bead Seat Diameter)BSO/Bike-Shaped-Object

Cable PullCable StretcherCadenceChain GaugeChain Guard/CoverChain ToolChain Tug/Chain Tensioner
Chainstay LengthChainsuckChamoisClipless PedalsCoaster Brake (foot brake / pedal brake)Crank

DerailleurDerailer Hanger/Derailleur RangerDisc HubDoor Zone
DropoutDropper PostDunlop Valve

e

Fender/Mudguard/MudflapsFixed-GearFlip-Flop Hub
Folding BikeFrame

Gear Inches
Groupset

HandlebarsHeadsetHose Clamp aka Jubilee Clip
HubHub Skewer

Internally-Geared Hub

j

Keel Tube

Lawyer lips/lawyer tabsLateral TubeLBS/Local Bike Shop
Luggage Carrier/RackLugged Frame

Master LinkMixte
Mountain Bike

n

o

PannierPlayPower Meter
Presta Valve/Presta TubePump Peg

Q-Factor
Quick-Release

REI (Recreational Equipment Inc)
RimRim Tape

SaddleSaddlebagSchrader Valve/ Schrader TubeSingle-speedSkewer
SpiderSpokeStemSuspension Fork/Rear Shock

Through/Thru AxleTire ClearanceTire Lever/Tire Iron
Tire SaverTrack Pump/Floor PumpTriathalon Bars/Triathlon Bars

u

v

Welded Frame

x

y

z

Bicycle-Shaped Object (BSO)
A derogatory term for a very cheaply produced bike with very low quality components. The components can be hard to maintain due to poor tolerances. BSOs are often sold at non-specialty retail stores.
The etymology of the term is uncertain. It appears in use in some parts of the English-speaking world. It may originate in the UK, as discussed at the link. Other languages may use terms equivalent to supermarket bike or department store bike. These terms are likely to be understood in English as well.

For instance the BSO pictured is being sold in the UK by ASDA (owned by Walmart) for £75. These bikes tend to be mass produced and sold in flat pack boxes for self-assembly.
Purchasers of lower-end bicycles tend to be less experienced cyclists who focus on price. Many BSOs carry features which are included for marketing purposes but are unnecessary for the typical end-user. Such features may include front and rear suspension, wide off-road style tyres and an excessive number of gear ratios. For cyclists who are riding on city streets or smooth trails, these features are unnecessary. Including these features reduces the budget available for better components elsewhere.
It is more advisable to search for a cheap second-hand bike in a similar price range from a more experienced cyclist or on eBay than to go for one of these.


How do I deal with a dog chasing me when I'm touring? Once I was riding my road bike down a rural road. I heard barking over my shoulder and saw two dobermans running toward me. I can't think of a time in my life that I felt more endangered.

I reacted instinctively and accelerated. Unfortunately I was on a gravel road and going into a bit of an incline. There was no way I could outrun those dogs. I looked back over my shoulder and they were no longer chasing me. The cycling gods must have been smiling on me.

Another time, in a similar situation, a different dog ran along next to me, barking and baring its teeth. I maintained my speed and yelled at it (trying to assert some dominance) until it got tired of chasing me.

These two experiences have done a lot to put me off touring alone.

How do I deal with issues like this?

Oh... where do I even start? I love dogs, I am crazy about them, too. I have 3 labs of my own. I am from a place where street dogs are very abundant. If you don't see any dogs in the next 100 yards, consider yourself lost! :D

I am barked at often, chased often, even confronted sometimes. I used to run away before, because it is what a normal guy does.

I learned a very big thing about dogs.

They chase wimps. It's like what a bully does, going after the weakest target. So, don't you dare run when you are bullied. Take a bite instead but stand your ground.
They sense fear. If you are scared while approaching a dog, he is sure to suspect you and bark/chase you.
They love challenges. If they think you are a worthy adversary they will confront you either to be protective or to see who is stronger in the area.

Me, for a guy, who was constantly afraid of dogs, was suddenly in charge, after learning a little of these dog psychology tips.

Therefore, please believe me when I am saying this

I have never run away from a dog. (Unless I am very very late)
If a dog is chasing me, I hit my brakes hard, and stare right at it. Mostly he will not come forward, and bark from a safer distance, kinda like maintaining a line. So I can finally get moving slowly.
If dog is coming towards you even when you are standing ground. Get off your bike, show him You are not going to wait around, when he is coming towards you.

  Show them, you are ready. Call it like "Bring it on"

After a stare down, do not make a hasty move. (Got bit once by a shepherd this way.) Take it real slow. Be calm.
Suppose that, despite your confrontation, the dog is heading towards you, accepting the challenge. Still, you have a big weapon: Your Cycle. Lift the front wheels high and start swinging it, right and left. That is sure to stop his pace to think a bit.
If a dog passes this point, and still heading towards you then you are in a serious point. Where there are only three things to do.

Surrender: Another  psychology of dogs, if they pass that point, they are challenging you head on. So, better lower your body, sit down. Let the dog be taller than you. Don't care about him, or look at him. Instead hook a headphone in your ear and listen to the music.  Music will calm your nerves down and send positive impulses for the dog to sense. Let him smell you. After few moments, just get up calmly grab your bike, start walking with it (but don't ride off) I have tried this so many times, its freaky but works
Call for help: If the dog has an owner, (s)he may hear you if they are nearby. Or somebody might help you get out of this trouble.
Get ready to fight: When nothing works, better get yourself prepared for the fight. From my own experience, dogs love to tear limbs. If they grab your limb, you just feel helpless. Avoid this

more on fight situation ....

Don't forget its an animal. Could be your last fight.
Pepper spray is handy as well if it comes to a fight - it's also useful for any muggers that might try for your wallet :) @Credit: Nate Koppenhaver
Protect your neck, hands and calf muscles at all cost. If they are hurt you have very slim of escaping.
Be defensive, rather than offensive: Let him make the first move and on retaliation you can do whatever you want. Effective targets are nose and eyes they will buy you a lot of time and you can make a run for it.
If you are lucky try to find a long stick. They are greatest weapons against dogs. Don't hit them. Just point it right at them and show them you will do it. Even a mini pump works, if you find nothing.
Don't let him corner you, keep the motion going,

  Normally when this happens, me and dog are generally circling each other

Make a little cage out of your bike. When you are cornered, this just might save your life.
Grabbing tail, makes him more angry, try to avoid that.
Grappling is only safe on the back of its neck. He can reach every other part.

How to avoid all this?

Dogs are very friendly creatures, you can be friends with them, no matter what. Treat them with respect.
Don't give them any reason to confront you.

If speed is the problem, slow down
If big size is the problem get off your bike
If he suspects you. Let him smell you.
Friendly look, with lovely hello, calms most of domestic dogs.
If you see a dog that is sure to bark on you, change your approach. Get off your bike, start walking with it

If the dog has a owner, better complain to them to have better control.
Report to the law, if owner is not helping you
Pack some treats, they are better as friends than adversaries.

BIGGEST SUGGESTION

Do not scare a dog and run away. They become enemy for life.

Update: Rabid Dogs

Getting into a fighting situation with a rabid dog, is more harmful than it should be.

One of my little story:

  One of my friend got into a similar situation with me, on a village cycle trip. A rabid dog was being chased by locals (its not abnormal here) and the dog out of fright ended up attacking us. My friend was a pretty agile cyclist, he immediately changed to defense position with his bike covering his entire body stopping the first attack. But, at a moment when dog was jumping at us, he used his elbow to hit the dog, but it bit him very badly.

Very torturous and painful moment we were in.

  Worst part than the wound was the infection.

So, I suggest full defence no offence as much as possible, but if you are a fighter/ Martial Arts Expert or know how to protect yourself very well, then yes, sick dog are very easy to knock down just aim for the nose.


Consultation needed! To repair or throw out? i found these two bikes by the dumpster- Dahon Boardwalk folding bikes. They are totally rusted by the salty air (it's a humid salty beach climate). The chain is rusted and when I push the pedal, the wheel does not move. The seat post is rusted. And the folding mechanisms are rusted.
I'd want them for a simple ride, 10mins into town and back- so might be worth it to fix. They don't have to be perfectly restored. What are the main things to evaluate before refurbishing a bike?
I'm willing to put down $150 on parts. I have basic tools and plenty of time.

Based on the photos you might not need any parts at all.
The chain looks pretty awful, and is likely siezed up, but a good clean is required to see if it needs replacing. I've had some ugly chains that were perfectly functional.
Brake pads is a common age item too - they get hard with age and braking performance suffers.  But pad replacements are cheap and easy.
Tyres and tubes can be affected by age, so inspect closely, and if they hold air pressure overnight you're probably good.
Grips can get tacky and feel awful, from UV.  Replacements are cheap, or you can simply wrap them in tape temporarily.
Saddles age and can attract tears, but tend to last mostly okay.  They're more expensive too.
As for the frame and mechanicals, the functionality is more important than its looks.
Folding bikes are also more useful and flexible than regular bikes.
Answer REPAIR simple at first, and see if there are any show-stoppers like frame damage.   Given you have two, its more likely to be a case of throwaway because too lazy, rather than both having the same terminal fault.


Difficulties with cleat pedals I have bought Shimano SPD pedals and MTB shoes recently. After riding for a while with cleats I decided to go back to regular pedals as I had trouble getting used to the SPDs:

With cleats power is decreased dramatically. It's became much harder for me to stick with fast riding group.
After riding, muscles are aching.
It's became more difficult to pick up speed at the start.

Most likely that's because others groups of muscles are working. However, more than one month passed and I feel like I am still much faster with regular shoes. With regular pedals I used to ride with middle of the foot over the pedal. That is the main difference.

One more thing - uncomfortable feeling in my knees. However, cleats position are set up completely fine, according to multiple instructions and tutorials.

I'm wondering, if anyone have ever faced with same issue when starts to use cleats. What changes can you suggest trying to alleviate the problems I have described?

I'm wondering, if anyone have ever faced with same issue when starts to use cleats. What changes can you suggest trying to alleviate the problems I have described?

After I first started using cleats, I started to developed knee pain. I asked about that here: you may like some of the answers. I discovered that in my case, the cause was the placement of my U-lock, which meant that my left leg travelled slightly further away from the top-bar than my right. Having the feet locked in place can cause problems (from repetitive strain). Some clips allow more freedom of motion than others. I fixed my problem by keeping my knees warm, and changing the location of the U-lock.

After a year and a half (10,000 km) I discovered that I can run on my toes, without putting my heel down, which I couldn't before. My calves had become stronger. People whose only exercise is walking (or cycling with the pedal under their arch instead of under the forefoot) may not have strong calves.

  With cleats power is decreased dramatically. It's became much harder for me to stick with fast riding group.

With cleats you can push in a circle, instead of just pushing up and down. For example when each pedal is at 12 o'clock, you can push it forwards.

Also I agree with using a lower gear and a higher cadence. If another cyclist overtakes me on my commute, I found that it's because I'm in too high gear: changing down one gear so that I can spin more quickly helps me keep up with them, i.e. it lets me deliver more power.


Folding bike cleaning I just got a Dahon Mu Uno 2011. I am really happy with the bike, but it's my first folding bike and I have noticed how quick it gets dirty. This is probably due to being closer to the ground than most other bikes.

What is a good cleaning routine for a bike like this? My previous bikes (road bikes, mountain bikes, etc) I only cleaned maybe once every month or two. But I feel this one needs more attention and I want to keep it happy. However, I am also afraid of ruining the folding mechanisms with excessive cleaning. Suggestions?

It would take a lot of cleaning to wear away the folding mechanisms on a Dahon. Unless you're cleaning your bike with steel wool and an angle grinder, you have very little to worry about. However, as you likely know, not cleaning your bike can result in excessive wear. The good news is that, since this is a single-speed bike, you have less to clean.

While folders do get dirtier than other bikes, because they're lower to the ground, cleaning one isn't all that different from cleaning a non-folding bike, with a few differences:

In general, you want to get the dirt off (including any road salt) or grit or sand, clean the drivetrain, then relube it. Make sure to rinse off any degreaser before relubing. Since a folding frame has more points of entry, you might want to take more care to avoid getting anything inside the frame - or spend a little time investigating to see if you have any dirt or grit in there.

Attacking the dirt and road grime with warm soapy water and then rinsing it off will be your best strategy. There's some controversy about whether or not citrus degreaser is bad for a bike's paint job, but I use it for stubborn bits of dirt and make sure to rinse it off thoroughly. I would avoid high-pressure water, or at the very least, keep it away from the bearings and folding parts.

I'm not sure what that plastic covering is on the chain, but it looks like it's there to protect it, which should make your job easier. You'll still want to remove the chain from time to time and clean it. On my Dahon Curve, I do it by removing the rear wheel and soaking the chain overnight in diluted degreaser, then rinsing the chain thoroughly. (The rear hub on a Curve can be a little finicky to put back on, but for reasons involving the internal hub. That's not an issue with the Uno, since it's a singlespeed.)

Cleaning smaller wheels can be a little difficult, because the spaces between the spokes and the rim are so small. However, there's less area to cover, so that evens out.

The folding parts on a Dahon include the frame hinge joint, the handlebar pillar, the seat post, and the stem hinge. They don't have any particular instructions for cleaning (soap and water will do a fine job), but you do want to make sure those are maintained.


9 to 11 speed partial groupset upgrade? Is it possible? I have a Shimano Sora 3500 full groupset (FD 50-34, Crankset 170mm length with BB RS500 (BC1.37 x 24), Sprocket 12-28) on my road bike.

I want to make a partial upgrade to 105 set due to my budget limit, by:

changing both shifters to 105 R7000;
changing the rear derailleur to 105 R7000 GS (long cage);
changing the cassette to Shimano 105 CS HG700, 11-34T (fortunately my wheelset can accommodate the 11 speed cassette);
using Shimano 105 SLX CN-HG601 11 speed chain; and
still keeping the current installed Sora 3500 FD, crankset, and rim brakes.

Please kindly share your thought whether is it possible or I need to go with a full group upgrade?

I believe the Sora's crankset and front derailleur should be fine, right?

Thank you.

The Sora front derailleur is not compatible with the front 105 shifter. Shimano changed the actuation ratio (ratio of cable pulled to cage movement) on 11 speed road groups.

The Sora crank is not compatible with a narrower 11 speed chain. The chainring spacing is optimized for a wider 9 speed chain.

YOu can look up Shimano component compatibility on their product information page.


How to clean sweat-soaked handlebars/handlebar tape? I just moved to a new apartment in a more humid climate, and while fiddling with my bike trainer setup, I've noticed that my gloves and handlebars are soaked with sweat at the end of a ride on the trainer. I know that sweat is corrosive to metal alloys, so what should I be doing to clean off the handlebars (and handlebar tape) and prevent or limit any corrosion damage? Is this something I should even worry about?

The salt from excessive sweating will corrode your headset bolts, bottle cage bolts, can corrode aluminum alloy in handlebars and can affect the paint on your frame. Riding outside on the road is less of an issue because sweat evaporates more easily and the force of the air rushing by keeps the sweat from settling easily. However, on a trainer, everything just runs right down off of you and on the bike and floor below. Sweat can build up on and under the bar tape if you let it. Google corroded handlebars, you'll find plenty of examples.

Replace the bar tape at least once a season, it will give you time to inspect the bars for any corrosion. It's most likely to happen where there are scratches in the anodized coating. In between rides, you can use a bit of water and tiny touch of dish soap to clean, be sure to rinse well.  Remember, use enough of water. You want to pull out the sweat and not let it build up there. The solution to pollution is dilution.

You can buy sweat guards which cover the headset and top tube to protect the other parts of your bike or you could just drape some towels. Additionally, a little lemon pledge furniture polish is a nice touch to keep your frame shiny and moisture resistant.


What is the best time to cycle during the day (traffic)? I started cycling a year ago and I have a favourite route for my time trial training since it is very hilly. However, I cycle on a major road (just outside town) and thus I like to cycle when it is less busy- both to avoid annoyances of having to come to a complete stop at roundabouts/traffic lights, as well as reducing the chances of getting clipped and in general being subjected to dangerous driving.

I live in the UK in a medium sized town, I believe around 120k~ people. So during rush hour, it's completely impossible to ride consistently anywhere. Since I am not a morning person, I have resided to cycling mostly in the evenings, around 8-9pm. But sometimes I would prefer cycling during the day so my question is the following:

What times of day do you usually find traffic most suitable for road cycling?

I realize that traffic varies, but there are still some general patterns that I wonder about: public holidays, Sundays, weekends in general, school-related traffic and so on.

For the UK there are traffic statistics available. This graph from the 2015 Road Traffic Estimates shows the general trend for cars.

There are detailed tables of traffic flow available.

There is also geographical data available in the form an interactive map. This isn't broken down by time of day, but should give you an indication of which roads generally carry more traffic.

If you're interested in when is the safest time to use the roads, there are statistics on road casualties by hour of day in this report (page 153 - Reported casualties by day, road user type and hour of day).


Are Shimano saint pedals suitable for trail / xc use? Thinking of buying the Whyte t129s, but not sure what flat pedals would be most suited for the xc / trail riding I'll be using it for. I looked at Nukeproof Neutrons and DMR V8s - prefer the look of the Saints, but worried they might be more DH/FR-focused and heavy on the climbs.

In the shortest way of answering this, yes, they will be suitable for trail/xc use.

All flat pedals are relatively the same. They only differ in the amount of pins, contact area, weight and their thickness.

You'll want something on the thin side for trail use, as you'll be pedaling quite a bit more than if you were on a downhill bike. This will help to reduce the amount of pedal strikes.

The weight is probably the biggest difference between all of the flat pedals. It is totally up to you as to what you find acceptable. For everyday trail use, the Saints should be fine and they should last quite a long while.


Can Presta valves suddenly lose pressure? I was doing my usual 15 mile round, about mile or two to go, when suddenly I realised my front tyre had gone flat.  It has heavy duty, mountain bike style, valves.
I haven't been able to find a puncture, re-inflated the tyre and so far it's holding 40psi. I rode it for a couple of miles without any problems.  Could it be that the knurled collar came loose?

Possibly the valve was contaminated with a particle or dirt and was not sealing properly leading to quick but not instantaneous loss of pressure. When re-inflated the contamination was dislodged and the tube holds pressure once again.


Waiver for medication during race? During the 2017 Tdf, Tim Wellens abandoned during stage 15 due to bad allergies and not being able to breathe.  The commentators said that his team would not "give him a waiver" to take allergy meds.

What exactly is a "waiver for medication"? Why does one need one during a major race and why would Wellens' team not give him one?

I can see how something like pseudoephedrine or a steroid could cause someone to test positive for prohibited substances in a race with strict substance rules and testing.  Is this the entire reason that he was not granted a waiver?

I would think Wellens could/should have taken something benign to help, like a benedryl, in order to continue the race.

There is asthma due to exercise. (Exercise-induced asthma). So one can have lung problem simply due to huge exercise. (not very likely in this case, but possible).

Waiver for meds in my view is "permission" to take a medication. E.g., epilepsy drug to prevent you from having seizure during the race.


What hand signals are there for communicating with others when cycling in a group? Recently I took a hit from behind. Fortunately it was just my friend's bike rather than one of those large-boxes-for-one-person. I was partly to blame because I failed to indicate that we were slowing down.

(However, as I understand the Highway Code, if you run into something that has the right to be in your right of way then you are to blame, so the incident wasn't really my fault but my friend's.)

Generally I rely on road-positioning to signal my intention, but I do stick my arms out for left and right if the situation deserves it. What other signals are there that I can use to show that I am slowing down, that there are hazards to avoid, etc.?

Are there any conventions, either in the Highway Code, as used in the peloton or in other cycling clubs that I could benefit from adopting?

I am also interested in best practice for signals that I can use with other road users, e.g. to let someone in a large-box-for-one-person know that I understand that it is their right of way - the equivalent of a flash of the headlights as it were.

I personally refrain from using single-finger gestures and banging on the tops of tin-boxes, however, it would be good to know what I can use to show my disgust/outrage in a way that is 'fair'.

If there are no online references, here would be as good a place as any to establish a list of 'to be universally understood' gestures and signals that can be used by cyclists.

Yeah, what Stephen says is about all I know (though I don't run with the racing crowd).  Pointing at road debris is commonly done, but probably useless, since it doesn't allow time to react -- I prefer to just yell "Trash!", especially now that I have a bad arm and the signaling is more difficult.

Using the hand signal (left arm (US) extended with elbow bent downward at about a 45 degree angle and with open palm facing backwards) for slowing is a bit more useful than pointing at road debris, but shouting "Slowing!" or "Stopping!" is still a better signal -- easier to accomplish, and more likely to get the attention of the rider behind.

And, of course, there's the shouted "Car back!" signal given from the rear (no possible hand signal here) when a vehicle is overtaking a group of bikes, and "On your left/right!" shouted when overtaking another bike.

(I'm sure that some cycling groups have additional agreed-upon signals, but I don't know of any others that would be generally recognized in the US.)

For motorists, I use the basic hand signals -- left arm extended for left turn, right arm extended for right turn.  I occasionally use the "slow" signal (described above) when needed to signal that a motorist needs to use caution (because, eg, of cyclists ahead that he may not be able to see), and I've used it once or twice when occupying a full lane to signal that I'm going to retain occupancy (such as when negotiating a single-lane bypass through a construction site).  I also sometimes use the left (US) hand extended, palm down, with a repeated downward motion to signal "slow down", when there are cyclists or some other hazard ahead.

When following others at all closely, cyclists need to learn to watch the feet, rear derailer, and rear brake caliper of the cyclist ahead.  These signal speed changes, and careful observation will clue in the cyclist behind even when the cyclist ahead fails to somehow explicitly signal.


Do chains on single-speed last longer than those on geared bikes? I have a Jamis Beatnik (love) and ride on the single-speed side of my hub.  I'm wondering - derailleurs seem to me like they might 'stress' the chain (even if only slightly) more than single-speed in the process of changing gears.  Are geared bikes' chains harder to maintain / shorter lived than single-speeds'?

(Background: I noticed I hardly have to clean my chain on my single speed, and it always looks great and feels tight.)

Single speed last longer and cost less.  More metal and less (no) flex.

SS comes in 1/8 and 3/32.
I would contend a SS 3/32 of the same basic construction is stronger than a 3/32 7 speed because it does not need to be built to flex and it is not flexed.

I am not finding any pictures of 3/32 SS chains and the chain on my SS bike is 1/8.
So I guess it is not really a straight comparison.
But a SS will take a 1/8 and geared will not so it is a fair comparison.

Also SS is built to take the abuse of a fixie.  In a fixie the chain has to take the braking force and gets hammered.  Note the question is SS not fixie.


What's the deal/appeal with loud MTB hubs? Why are a lot of mountain bikers looking to get hubs that make loud sounds? Does it have an advantage or use on the trails?

As the other answer indicated its more about the quality of hub than sound. It just so happens that many higher end hubs have a more distinct click to them. This is present for multiple reasons. The spring tension on the pawls tends to be higher than cheap mass produced hubs, letting them "snap" down onto the step for instant engagement. They are also more finely machined than standard entry level components allowing very fine tolerances and clean crisp operation.

The materials used can sometimes effect this as well but the alloys 6061 and 7075 are common in higher end hubs. Steel would have less of an audible click as it would muffle it some and generally steel hubs are not the same quality.

With that said there are silent hubs, generally used for police bikes so that they can be a little sneakier when rolling up on a perpetrator. There are also high end hubs that make less than standard amounts of noise.

I also think a big part of why people are drawn to them is the fact that it makes them feel like they have something nice, sense a lot of people now a days do associate it with higher end hubs.

The only real benefit relating solely to the sound i can think of would be for mixed trail use where it may help alert others to the fact you're barrelling toward them.


How much steerer tube length do I need on my suspension fork I have survived BB hell with minor bruising to be greeted with another challenge replacing forks.

I have a 1996 TREK 8000 SHX (yellow) and a 2002 TREK 4300 (silver/blue) MTB bikes. Both bikes have 21" frames. I want to get my wife and I into trail riding and I am looking to replace the suspension forks.

As beginners, I do not want to break the bank buying these forks. I know a crucial point is getting the steerer tube length and diameter correct. What are my considerations? Is there a way to look up the lengths of the tubes for 21" frame? I do not have the physical old parts.

Thanks in advance.

No, there is no way to look up the lengths of tubes. According to quick web search, both bikes have 1 1/8 threadless headsets, so that is the diameter you should shop for.

What you can do is measure the head tube of the frame, add a couple of centimeters for headset, around 5 centimeters for the stem and room for enough spacers to get the handlebars at the height you want.

Typically threadless forks come with very long steerer tube to fit the largest frames, and you are supposed to cut it to correct length yourself. When in doubt, leave some extra length and fill it with spacers until you are sure that you want to keep the bars at lower height.


Could you please identify this wtb cantilever/roller cam brake I've had some issues identifying this brake, and while I do know its wtb and circa late 1980s-early 1990s thats it. Any information would be appreciated. To clarify the parts were not original to the bike frame, as its a 1993 diamondback arrival.

Those brake boosters are definetely by WTB, you can see a logo on third photo. I'd gues that whole assembly is by WTB too, at least google images return very similar results (this post especially, scroll down a bit for a picture).


What are the strengths and weaknesses of Rido saddles? I've started riding more often now (big plus), and as a result am getting, ahem, saddle issues with my classic San Marco Rolls saddle. I'm an average build, 5' 8-9". The saddle issues are mainly chafing at the top of my legs, some more serious skin damage, and general soreness.

I've heard good things about Rido saddles. Specifically that they transfer the weight from the perineum to the assbones which are better built for weight distribution.

What are these saddles best and worst at? Are they good for particular types of riding, or riders with particular builds? Are they good for particular kinds of bikes? I ride a Batavus Pro Team road bike circa 1990 which is about right size for me.

Is there anything specific to this saddle that has to be taken into account, position of saddle fore and aft, angle of saddle, or position of handle-bar stem, etc?

Yes, I think a Rido is worth trying in your situation. Of course, make sure your bike fits you properly, saddle height and tilt are properly adjusted, and so on.

I found my Rido saddle to be good for riding with padded shorts, but not so comfortable with street clothes. The saddles seem to be designed for moderate distance riding in a sporty position.

Of course, the only way to tell if this saddle will work for you will be to try it, but I think that a saddle like the one I had (see the picture) may work for you. When I rode the pictured bike for rides of half an hour to 45 minutes, the Rido took care of my chafing issues (the same as the ones you're having), since the saddle's nose is fairly narrow. When I replaced that bike with a Bike Friday and a Brooks, I replaced the Rido with the original saddle and turned this bike into a city pootling bike.


Drivetrain changed - new cranks further from bottom bracket On the weekend I did an overdue drivetrain change. Everything went fine and runs rather smoothly, but I had to adjust the front derailleur a lot. It seems like the new cranks are about 5 mm further away from the axle than the old ones.

I changed from Shimano FC TY301 to Shimano FC-M361.

Is the described discrepancy a likely case, or did I simply not push the cranks far enough onto the axle?

I think what is going on here is that you were running a 47.5mm chainline (standard for MTB triples, see here) with the FY301 crank, but the M361 crank gets you a chainline of 50mm.

When switching out three-piece cranks you have to pay attention to the chainline and you also have to look at cartridge bottom bracket axle lengths and potentially replace the BB along with the crank. Different model cranks require different BB axle lengths as the axle interfaces of different models are not in the same position long the axle axis relative to the chainrings.

Shimano helpfully provides extensive specification documentation for their products but figuring out the proper BB for a crank is somewhat complicated. We can find the crankset ('chainwheel' in Shimano parlance) specs here.

Do a text search on that page for 'TY301' and 'M361' and you should find the entries we want. Note the TY301 has a chainline spec of 47.5mm (normally, there is a 50mm option too)  and the M361 has 50mm. The TY301 should be paired with a BB-UN100 or BB-UN26 bottom bracket, axle length code D-NL (for 47.5mm chainline). The M361 should be paired with a BB-UN26 bottom bracket, axle length code LL123.

If we look at the bottom bracket specs here (search on the page for 'UN26') we see that the LL123 code means 123mm, D-NL means 122mm (if I read the specs correctly). 1mm difference isn't enough to worry about.

I think if you measure the chain line with the M361 crank on (distance from the center of your frame seat-tube to the center of the middle ring) it will be about 50mm. If your measured chainline is about 55mm, you must have had the 50mm option on the TY301 crank, so you definitely need to replace the BB with the correct one for the M361.

If your original chainline was 47.5mm, you could replace the BB with one with a 118mm axle to drop your chainline back, or you could just run 50mm. If you derailleur can reach the big ring OK I'd be tempted to leave it as it is. If you plan to replace the BB make sure there is >5mm of clearance between the  rings and the chainstay - presumably there should be, unless you got larger rings with the new crank.


What are the rules about take a bike on London Dockland Light Railway (DLR)? I know that the rules for the DLR are not the same as the Tube, but what are the rules?

Only folding bikes are carried on the DLR, and they must be 'totally enclosed in a cover'

This website has all rules for bikes on public transit for what seems to be most companies in the UK. Check it out.


Why are chainrings 50T and larger five-bolt rather than four-bolt? I've noticed that chainrings 50T and larger all use five bolt holes instead of four, invariant of BCD. How come? Is this simply due to tradition or is there a mechanical stress reasoning?

TL;DR: It's just marketing.

In the 1930's, René Herse used three-arm, 70mm BCD cranks, and you can buy 50T chainrings today that fit that specification. In 1949, Stronglight introduced the Model 49, that bolted the big chainring to the crank with a tiny set of five bolts near the spindle, and then bolted a secondary chainring directly to the first. In 1958, Campagnolo introduced big 5-arm cranks (151mm BCD!).

Mostly everyone adopted and refined variations of the five-arm design for the next four decades (TA tried six bolts for a while), until Shimano introduced the 4-arm XTR crank (112mm BCD) in 1996, followed up by more 4-arm cranks (104mm BCD) for LX and XT in 1997.  The marketing reason was that they were lighter (slightly), but it also meant that Shimano was the only company selling chainrings to fit the nascent standard.

Shimano was the 800lb gorilla of the 90's MTB marketplace, and where they went others followed. Over the next decade, 4-bolt cranks became common in mountain biking, where smaller chainrings are the norm. Hence the lack of large chainrings in four-bolt patterns.

Attempting to make the same leap again, the 2013 Shimano Dura Ace 9000 road crankset uses a non-symmetrical 4-arm crank with a 110mm BCD and up to 53 teeth. Once again, the stated marketing reason is weight - apparently this crankset saves 12 grams over the 5-arm Dura Ace 7900 crankset.

Much reviewers ink has been spilled over the stiffness of the new four-arm design and it's underlying strength, but it's not really clear that the cranksets of today are dramatically superior to those 3-bolt cranksets of the 30's, which were used to power tandems to the top of the Poly Chanteloup - and modern reproductions of those cranks are still lighter than the modern Dura Ace cranks.

More reading: Jan Heine's History of Aluminum Cranks, Stronglight 5-arm crankset timeline,  Museum of Mountain Bike Art & Technology Shimano timeline, Cycling News Dura Ace 9000 review


How is this kind of cycling correctly called? Sometimes I like to make rather high-speed descents (during which I also make jumps) in the forest near to my house. I want to know how this kind of activity is correctly called. Is it downhill, freeride, etc.?

From your description it's hard to say exactly what kind of riding you are doing, all forms of mountain biking can involve going down hills quickly and jumping. If you want to be specific it sounds like it fits into one of these categories -

Trail Riding This is a good catchall term for recreational mountain biking where the trail is the most important thing - It includes climbing and descending, typically on singletrack. It's possible your wheels will get off the ground, but not mandatory.

All Mountain Again this includes climbing, but all mountain riding focuses more on going down than getting up. A all mountain bike will generally be heavier and more robust than a trail bike - it needs to handle higher speeds and bigger impacts.

Downhill Are you just interested in getting down that hill as quickly as possible? Are you pushing/getting carried to the top? Then you're riding downhill. You'll probably be jumping, and you'll probably be going very fast.

Freestyle Like downhill freestyle is all about the descent, but in this case style is more important than speed. If you're riding freestyle you'll be doing tricks and stunts on the jumps and drops.

Bear in mind that these aren't strictly defined terms, and are prone to change.


Center Lock to ISO Disc Adapters We've got a bike where the front hub (Shimano Alfine dynamo) uses a Center Lock rotor and the rear hub (also Shimano, go figure) uses an ISO rotor. The front hub is giving me fits trying to sort out why the rotor rubs intermittently, so I thought I'd try replacing the rotor.

My thought is to get a Center Lock adapter and use an ISO rotor so that both ends of the bike would use the same type of disc. Seems like it would make life and maintenance a bit simpler.

Question 1: Is there any reason why this would not be a good/acceptable idea? Are there substantial advantages to Center Lock?

Question 2: Does the adapter convert a Center Lock hub to an ISO hub or does it convert an ISO rotor to a Center Lock rotor? In other words, do I attach the adapter to the hub (and leave it there) or do I attach it to the rotor and move it from rotor to rotor as they wear out?

The advantage to centre lock is that it's easier to change rotors. You undo one nut and slide the rotor off. ISO requires 6 bolts to be undone/redone. It's also possible to build a lighter rotor more easily, and you can make smaller centre lock rotors than ISO ones (should you want a 50mm rotor)
The adaptor does both, that's a question about how you choose to look at it.

Both these questions seem to assume you'll be changing rotors around a lot, when most people very rarely do this. Right now you have a problem so you're focused on the issue, but once you have something that works you'll likely not deal with that area of the bike again. So I'd be worried less about how much work it is to do a part of the current task, and more about whether you can stop the rotor rubbing.

In my experience the intermittent rubbing is never related to the mounting setup, once it's installed correctly and assuming there are no mechanical failures. Basically, if you can make it work even for a short time that's not the problem.

The most common cause of "sometimes it rubs, sometimes it doesn't" is bent rotors, so the slight variation in caliper return-to-centre means sometimes there's a rub. But that's an easy fix - put a straight rotor on and see what happens.

The other, more annoying issue, is that not all wheels sit tightly in the dropouts. That means that the wheel can shift slightly, usually under heavy braking. When that happens you'll often get rubbing that won't go away until you release the axle and re-seat the axle in the dropouts. At which point the rubbing goes away until next time you brake heavily. That's a design issue, and unfortunately the standard we have makes it inherent to the way bikes are built. It's more of an issue on front brakes (where the braking force pulls the wheel out of the dropouts) than the rear (force is up or back depending on caliper location).

Fixing the latter problem is tricky, and the solution I've used is a washer on the outside of the dropout sized so it engages with the "lawyer lips" all the way round. It also needs to snugly fit the axle, obviously. Which usually means filing, and is a tremendous pain in the proverbial.

A more permanent but still ugly solution is to use a welder to fill in the dropout a little then file it to exactly match the axle you have. Then repaint the fork (or frame) and re-file the new paint off the contact area (so you can get the wheel in). The real solution is to use through axles that bolt solidly in place, or mount the caliper on the right hand side fork blade instead of the left one. Hardly anyone does either of those.


Could I have the brakes changed? I have a Flying Cat brand electric bike. It is the Style City model.
Currently it has V-Brake SHIMANO AV/AR.
Full details of the bike are here:
http://www.flying-cat.fr/velo-ville-electrique-style-city.php

I am wondering if changing my brakes to progressive brakes (disc brakes) is a possibility.

This is because while cycling to work someone cut in front of me and I instinctively braked hard. The bike slipped and I fell and have hurt myself. Apparently progressive (disc?) brakes could make my braking safer and more controlled.

I think you have a misconception about disc brakes. You may have heard that (hydraulic especially) disc brakes allow better modulation, which does allow for increased braking control, but if you yank the levers hard, they provide instant, full power braking.

Properly set up V-brakes can provide sufficient modulation to be controllable. Your evidently offer enough power to stop quickly.

Practicing emergency stops on grass is probably a good idea so you have more control of the bike under hard braking.


What is a wireless crankset? For example this (rather expensive) item: http://www.wiggle.co.uk/sram-srm-powermeter-pro-wireless-bb30-double-chainset/

What is actually wireless about it? Is this for a cadence meter? Wireless shifting?

The crankset is not wireless, the power meter inside the crankset is wireless, the power meter inside measures your power output and wirelessly transmits the data to a head unit for display near or on your handlebars.


How Dicey are super cheap brake cables? I was going to buy some super cheap - I mean barely more than 50 cents per meter - brake cable.

Am I in any danger of sudden failure?  I don't mind replacing the cable after a year or something, but I'm sort of worried about it outright breaking and then trying to kill me.

Steel wire is cheap (if it's not stainless). Even the outers aren't very sophisticated. So it's possible to meet the basic requirements for very little cost. For more money you get a lower friction lining and better tolerances, which are worth having in many cases (including beater bikes and BSOs with marginal brakes).

On the other hand if you need to keep taking up slack in the cable, something is wrong. I'd expect to set them up, ride a bit, tweak and then get hundreds of miles before needing to tighten again (unless your pads wear very fast). If that's not the case, something is creeping, stretching, fraying or otherwise letting you down.

After any work on the brakes, ride cautiously for a bit. Test for emergency stop rather than relying on it. For major work (like new cables or unfamiliar new pads) I like to do one brake and give it a good test before doing the other.


What are some key road flat pedal bicycle adjustments that affect neck strain? Over time I grew to understand that different adjustments (saddle, handlebars, pedals, stem) affect different parts of the body. Often multiple at ones and often indirectly - by altering something else directly and then for example putting more strain on other parts of body indirectly because of that. My girlfriend recently started riding a road type bike (gravel) with flat pedals. Her neck hurts. I think my neck hurt when I became a roadie as well. But that went away after a few months. I'm not sure if I accidentally fixed my position then or if my neck muscles/whatever is there adapted.
I have tried changing her handlebar tilt upwards, and ever so slightly (1.5mm) moved the saddle to the front. I'm pretty sure there is nothing extreme about her position or the bike setting. The frame size is definitely good. I have also suggested that she moves her body around on the bike: stand from time to time, move the neck every few minutes, change arm position on the handlebars.
Does anyone have a good advice which parts of the bike can fiddled with to experiment and try to fix the neck pain?

If a rider is suffering neck pain, one of the first things to try is removing any visor from the helmet.  MTB helmets frequently come with some kind of sunshade/peak/bill horizontally over the eyes, and when on a road style bike, that means craning the neck up more to see underneat.  So unclip it.
Rider can also try to ride with a straighter back.  Its easy to hunch over so one's spine is curved.  That also puts strain on the neck.  At least try and straighten the back periodically while riding.
After that, it becomes a bike fit process, which is getting a bit much for an answer here.


Should I grease pins when re-installing them on cottered cranks? I'm restoring a vintage Peugeot with cottered cranks.  When reattaching the cranks to the bottom bracket spindle, should I grease the pins or put them in dry?

Yes. The grease will aid in installation as well as later removal.


Can a Shimano Alfine 8 speed be reduced to 120mm hub spacing? I would like to buy a single-speed bike that happens to have 120mm hub spacing, and add the Shimano Alfine 8-speed hub. That hub, however, seems to have a 135mm spacing.

Can the 8-speed Alfine hub be modified (in less than two hours, with standard hand tools) to 120mm?

No, with either the 8 or 11 speed Alfine hub, there is no possibility of using it on a 120mm frame. The hub shell itself is about 120mm wide, without the cable carriers for shifting, or any spacers at all.

If, as it appears from your 120mm reference, you are considering a fixed gear frame with that spacing, then you should reconsider. 120mm spaced dropouts are typical on  track specific frames, or track frames from very traditional builders.

Frames like these will also have geometries which are not suited to use on the road, and I assume you don't want the bike for the velodrome, since you want gears.

There are plenty of fixie frames with 130m or or 135mm dropouts. If it is 130mm and steel, you will have no trouble adjusting the frame to fit a 135. Otherwise, you should use a 135mm spaced frame, which likely means a hybrid or mountain bike single speed frame, or a frame with a concentric bottom bracket.


Are road tyres suitable for any off-road riding at all? I'm looking to buy a bike for my commute - 6 miles a day. The commute itself is all on roads, so naturally I'm looking at road bikes. My main worry is that if I invest in such a bike I won't be able to ride off-road at all, for example down a towpath (Towpaths can have very rough surfaces).

Would I be better off investing in a light hybrid bike (with thicker tyres) over the road bike, given that I might want to go off-road some of the time?

If you're looking for a general purpose bike for commuting and towpath riding, you probably want to avoid a standard road bike, they are very specialized and have very small tire clearance.  Typically supporting tires no larger than 28mm and often lack mud guards or rack/pannier mounts.

However, touring bikes or steel cyclocross bikes (if they have rack and fender mounts), tend to be great choices for those purposes.  Both will often have clearance for tires up to 35mm or larger which you can use for off road riding and have a more traditional road geometry versus the more upright hybrid geometry.  However, if you prefer the more upright stance and flat bars, then a hybrid may be more well suited to you.

I would make sure that whatever bike you get does have rack/fender mounts if it's going to be used as a commuter.  You never know if you'll want to start using a rack and panniers to carry your gear off your back or fenders to keep you drier in the rain.

You can get knobby tires for any of these bikes, but I would stick with high quality, puncture resistant road tires wider than 28mm.  Even slick tires that are 35mm should be fine for towpath riding, I wouldn't take them on singletrack though.


Bike with coaster brake and gears for teenager with disabilities I have a 13 year old with a form of muscular dystrophy.  He's well physically, though not as strong as most kids, and can ride a bike.
We got him a cruiser bike, which I then modified to make appropriate for a young man, a couple of years ago and he does well on it.  However, it only has one gear and I have to push him up hills (and we live at the bottom of a hill!).
I've looked into bikes with an electric booster but am concerned they'd go too fast.
What I'd like to get him is a bike with a few gears (so he has a better chance to make it up the hill) but I think it has to have a coaster brake.  He has significant myotonia in his hands and, while he could operate gears, we don't want to trust his hands to stop the bike.
I've looked and looked and cannot find a bike with gears and a coaster brake.  Are there any out there?  I'd appreciate it if someone could point me in the right direction.  Thanks.

If I understood your question, you may want to look into internally geared hubs, it seems they are exactly what you are looking for.
I thought they were fairly popular, so I would be surprised if you really have not come across these - so I am sorry if I missed the point.
A landmark feature of gear hubs is that you can change gear while stationary - it sounds like this could be beneficial to you too.
Have you spoken to someone in a good bike shop? I would imagine it should be easy to find one where you can test ride a bike with a gear hub.
Alternatively, you could google something like "bike with sturmey archer gears". You mentioned "cruiser bike" - this seems to be a fairly broad term, if you can add the brand and model of the current bike (or a photo of it), people on here may be able to suggest similar alternatives, and I think it would be within the stack exchange rules about product recommendation.
If all else fails, you could probably get in touch with a bike manufacturer that sells bikes with these, to see if they can assist with getting a test ride? This almost sounds like a perfect story for a bike maker's Public Relations. Good luck and I'd love to hear how you got on with this!
Daniel R Hicks commented that gear hubs with a coaster brake are rare. Sturmey Archer website lists a few, you can't filter but you can search it for "coaster". I believe the company had some difficulty but seems to still be in business.


When to change winter tires for bicycles At work, we discussed when to change to winter tires for bicycles (and cars). We assumed that temperature was the key factor and I used a program (Mathematica) to check the mean temperature in Stockholm (see this question Probability of ice in Stockholm).

My question is: besides the risk of ice, what are key factors for deciding when to change from summer tires to winter tires? E.g. is the rubber of summer tires negatively impacted when it gets colder.

The cost of burning through studded tires can start to add up. I find it more efficient to keep a pair of studded tires installed and ready to go on an older pair of wheels, and I can just throw them on if it looks like it's going to be an icy day.


What should I look for in a cycling jersey? Time has come to refresh the wardrobe a little, and the old woollen cycling jerseys need some young blood to compete against.  What should I be looking for in a modern cycling top?  Is lycra used anymore?  Does the cut of the jersey (other than being tight) have any effect?

Fit is the most important thing I look for.  A cycling top should fit snugly, without being skin-tight.  Having less extra fabric will mean less air resistance, which makes a surprising difference at higher speeds.  Also, too much excess fabric will flap in the wind, which can be annoying too.

Make sure that the length in back is long enough to cover your lower back when you're riding in an aggressive position.  If a long-sleeve, the sleeves need to be long enough to cover your wrists with your arms extended out front.  (some normal clothing fails these two checks)

One last caveat about jersey style:  make sure the zipper opens far enough for you to be able to take it off after a long sweaty ride.  I have one with a short zipper and it's a real struggle.

For materials, there's lots of nice synthetics to choose from that are lightweight, wick away moisture and are very comfortable in hot weather.  But for cool or wet conditions, nothing beats wool.


swap Shimano Alivio gear indicator for cover plate I want to move my brake levers and gear shifters around a bit.  The problem is my gears (Shimano Alivio, bought 4 years ago) have a large gear indicator on it.  This is meaning that either the brakes are too far in from my hands, or the gear shifters are too close to my hands and I bump into them and find it awkward to change gears.

I have taken the cover off of the front shifter which comes off nice and easily, but the mechanism is slightly exposed below, so think I need some sort of cover plate or the gears will get damaged over time.

Is there such a thing?  Has anyone had any experience with this?

Nope - there is no cover option. You can live without the indicators - I don't think I have ever looked at mine in earnest. Given the situation you can just tape it up as best you can to make sure none of the internals are exposed to the elements.

There are plenty of other shifter options that all cost money that will be considerable compared to the 'OEM' cost that your cycle manufacturer paid.

If you are willing to spend some money then you can get some very fancy Shimano shifter/brake lever combos that will have the required ergonomics. Or you may want to consider the 'unfashionable' gripshift option. Gripshift are fantastic for everyday riding and compatible with Shimano 8 speed (which I presume your Alivio setup is). People do get rid of the gripshift and put the parts on ebay. They are frequently found on 'affordable' kids bikes and can vary externally in condition, however the internals are invariably sound as there are no moving parts. Give them a go, they are fun!


Where can I get some rags? As I'm getting into the habit of cleaning and maintaining my bike more often, I am burning through my stockpile of rags. Up until now I have been using worn-out clothes as rags. I am going to run out soon and I need to get some more.

My LBS (big chain store) just said they get a large, vacuum packed bag of rags delivered from head office every so often. They were kind enough to give me a bunch for free and they seem to be old bedsheets. Whilst I could go to a charity shop and buy some sheets, I'm not keen on cleaning my bike with something that someone might want to buy to wear.

What do you use as rags and where do you get them from?

The best shop rags I have ever used are blue medical operating room towels. They are much stronger than old clothes. They are intended to be thrown away, but I wash them and use 'em again.

However, I don't know where to get them. Maybe if you have an O.R. doctor or nurse in the family.

(I also use these to clean the kitchen, to wipe up spilled soup, to wash a car or bike, as hot pads, and as napkins. I put a damp one under the cutting board to make it stable.)


Why the small difference between common sizes of handlebars (31.8mm) and MTB seatposts (31.6mm)? Many handlebars have a 31.8mm clamp section, and a common MTB seatpost size is 31.6mm.
I know these are both around 1 1/4 inches. Why the 0.2mm difference though?

Frame tubing is generally standardized by external diameter to imperial dimensions in increments of 1/8 inch, which makes it a lot easier to standardize things like front derailleur clamps.  Seat tubes therefore tend to have external diameters of 1 1/8” (28.6 mm), 1 1/4” (31.8) or 1 3/8” (34.9 mm).
Handlebars are similar. Though there has been more variation historically (eg 26.0 and 26.4 mm in addition to the imperial sizes), modern bikes tend to use handlebars with imperial sizes for the clamped diameter.
The problem, however, is that the internal diameter is not standardized, because it depends on the thickness of the tubing wall, which varies quite a bit. High quality lightweight frames can have very thin-walled tubing, while lower quality frames might need thicker walled tubing to get the same strength. So two seat tubes that are both 28.6 outer diameter could have different inner diameters.
Since the seatpost diameter has to closely match the inside diameter of the seat tube, variation in inner diameter of seat tubes has resulted in a large number of different seatpost diameters. Makers of more expensive bikes have largely converged on 27.2 and 31.6, but there are still many others, especially on lower end bikes.


What kind of brake pads for Dia Compe centre pull brakes I have some Dia Compe center pull brakes shown below.  I was wondering what the best type of brake pads are to use for these brakes.  Looking around at pictures on the internet, many people use standard road caliper pads, while others use old style pads rectangular block pads (as in the picture) to preserve the authenticity. I've also seen a few examples of people using v-brake pads. are there any advantages to using a specific type of pad on brakes like this?  I really don't care about esthetics, and I'm really just looking for what will provide the best braking experience.

You can use V-brake pads, but they tend to be longer and can create clearance issues. On the bike I currently have set up with those pads on Dia-Compe centerpulls, the shoes hit the fork when the brake is open, making wheel removal difficult.

edit:

As ojs notes below, road caliper pads are probably your best bet. They also tend to be on shorter posts, so they don't limit tire clearance as much as V-brake pads.


Can you identify this vintage Moor MTB I've recently acquired this bike:

The Moor brand seems to be coming from Denmark. However, the SFMK CSCM sticker seems to be referring tot the "Suisse Motorbike and Bicycle Union".
The bike was bought in Germany.
All the components are Shimano Deore.

Does anybody has more information?

Thanks

It think it's a Swiss bike.

The top tube says Velo Sport Walpen Fiesch.

Walpen is a Swiss surname from Valais in Switzerland.
Fiesch is a municipality in Valais in Switzerland.
There is/was a Swiss bike company called Moor, which on older bikes carry this head badge:

I found an old German eBay listing in the Google web cache for this bike in Berlin, which doesn't give much more info, but the bike was also bought in Germany.

  26" MOOR MTB, Retro, Vintage 54cm. kaufen in Deutschland

  Preis: 100 €

  Details

  Erstellungsdatum:
  21.04.2016
  Anzeigennummer:
  456744407
  Art:
  Herren
  Schlagwörter:
  26 Zoll Shimano

  Beschreibung

  Verkaufe ein sehr schoenes und originales MTB der Marke MOOR 26 Zoll, RH von 54cm,mit ,21 Gänge.komlett Shimano Deore ausstatung,Lichtanlage und Schützblech Das Fahrrad ist gebraucht aber im sehr guten Zustand,Preis 100 Euro

And of course "SFMK CSCM Service Garantie" points to Switzerland too.


Mixing various spoke widths in a single wheel So the story began some 4 years ago, when I bent my rear derailleur hanger while crashing, and my  chain got stuck between the cassette and the wheel scratching a few spokes. Everything was fine until this year when some of these spokes started to snap and I had to replace them.

I have 32 DT Revolution spokes that are 1.8-1.5-1.8mm in diameter and replaced 4 of them from the drive side to plain 2.0mm spokes. I trued the wheel with no problems and after some 500km everything looks fine.

The question is: for how long? Will the thicker spokes exert more side force and lead to over-tensing the other side? Or is there a risk in quicker fatigue of spokes on either side?

Given the age of the wheel, you're going to continue to snap older spokes from time to time. Don't worry about the gauge of the replacement spoke. Assuming it's within the range of appropriate tension, as long as it pulls true there's not much to be concerned about. I have multiple wheels with some of the thinnest gauge spokes available (Sapim CX Rays) with straight gauge replacement spokes. No issues to report.


Rear derailleur movement where it is bolted to hanger I've checked the hanger and that seems solid. There is some movement/wobble in the derailleur at the bolt that connects it to the hanger, like it's not quite tight enough even though it's tightened as far as it will go. When followed down to the cage it feels like 1-2mm in sideways cage movement, maybe more - it feels significant anyway. The cage itself is definitely still solid on the derailleur, and it lines up straight under all of the sprockets.
I took the derailleur off, cleaned the threads and everything around them including the c-clip, refitted but still some wobble. I think it's affecting my shifting as the cage might not necessarily return to the exact same place at the extremes of the cassette meaning I can't find a cable tension that works for all gears.
Is there anything else I can check before trying a new derailleur? (I have a medium cage ready to go but the current short cage has been working fine so reluctant just to retire it)
I did notice that around the c-clip it wasn't an entirely flat surface, there were a few metallic ridges the were higher around the edge than other parts of the surface. Are they there for a reason and do they have to be located in a certain place? It's a Tiagra derailleur, looks pretty much like this: https://i.stack.imgur.com/LsyF4.jpg

I think you cannot do anything with this wobble. I have similar one, opened the derailleur, but inside I just found out that the part that goes around that bolt inside is probably slightly deformed. It is a metallic cylinder - a hole that goes around the bolt, but when it becomes deformed to be slightly wider, it just causes some play of the derailleur on the hanger.
You can test whether my description fits your situation by wiggling the derailleur and looking what actually moves. In my case the bolt and the flat metallic part connected to it stay firmly connected to the hanger and what moves is the actual body of the derailleur (painted).


How to adjust Shimano hydraulic brakes contact point? The title might be wrong, I am not familiar with the terminology here.

I just got a BR-M445L front hydraulic brake. Installed it - this stuff is MUCH easier to install than a cable disc brake.

Now my problem is that in order to apply maximum braking force, the lever has to be pulled all the way to the handlebars.

I discovered the reach adjustment screw on the lever. With this screw, I moved the "at rest" position of the lever further from the handlebars. Thus, the situation is somewhat better now.

However, what I would want to do, is leave the lever not too far from the handlebar, and remove the "free travel" - the part of the lever's path, during which the pads do not contact the disc at all.

In other words, I would like to have 2-3 cm of travel of the lever, instead of 5-6.

There are a couple of screws on the calliper, but I am scared to touch them, before knowing what I am doing. One is on the entrance of the hose, similar to a cable brake adjustment screw. The other is at the base of a small opening, covered with a cap.

The brakes should adjust themselves automatically. Try pumping the lever all the way a couple of times. If that doesn't help, or the contact feels squishy, the brakes probably need bleeding. Either do that yourself or take the bike to your LBS.


What should I look for in choosing wheels for a road bike? I have a commuting/touring bike and my riding is a good bit of commuting mixed with weekend rides of up to 50 miles.

In my lame knowledge, I'll assume that lighter wheels can be had when you spend more money, but what are other things to look for or avoid when choosing wheels for a non-racing bike?

If you're doing mostly commuting I'd look for strength above light. Go for something with more spokes and with a 3 cross lacing pattern. You want something that is reliable. Of course you weight is a consideration so there is always a trade off between that and durability.

Going with something with radial (straight) lacing up front can save weight and you're less likely to break a spoke on the front wheel so there is less chance that durability will be a factor.


Front derallieur compatiiblity I am in need of a front derailleur and my previous one is a Shimano Altus 3x8, (triple chainset), (8 speed cassette).
Would any other like a tourney or any others work?

The compatibility info at si.shimano.com is a great resource for Shimano compatibility questions. You can also find the specification handbook (including current models on the web version and pdf archives of the handbook going back to 2004), as well as service documents by model (dealer manuals, exploded views, etc)
The parameters that need to be compatible for a front derailleur are:
Front speeds: triple or double
Top gear teeth: the number of teeth on the large chainring. an FD outer cage plate meant for a 38T will not sit low enough on a larger chainring like a 44.
Rear speeds/chain: different numbers of rear cogs require different chains, and both the width and the profile of the FD cage are designed to match a specific chain. 6, 7, and 8 speeds all use the same chain width.
Shift family: how much cable does the shifter pull? When it comes to switching front shifters, the front drivetrain compatibility chart is not quite exhaustive. I believe all Shimano MTB 3x front shifters pull the same amount of cable, but I could be wrong on that.
Total capacity: maximum accepted difference between big chainring and small chainring teeth count.
Top-mid tooth difference: for triples, how much smaller is the middle ring than the big ring? 3x FDs tend to have some shaping that’s specific to where the chainring is expected to be.
Chainline: distance from the center of the bike to the center of middle chainring, or the average of the chainrings on a double.
Chainstay angle: angle between the line through the center of the  rear axle and the bottom bracket, and the seat tube to which the FD is mounted. Only a concern generally for clamp band derailleurs, and generally only for MTB type front derailleurs. Can be measured directly, found in the geometry tables for a bike, or by referencing the old FD’s specified range of chainstay angles.
Mount type: how it attaches to the frame. Could be a:
-Band clamp: usually includes shims for use with smaller seat tubes
-Braze-on: road bikes, sort of a curved plate on the side of the seat tube, with a vertical slot for the fixing bolt
-Direct mount: mountain bikes, either High Direct/DM, consisting of one threaded hole next to a vertical slot/groove; or E-type/Low Direct, with two bolts a little under an inch apart horizontally
-E-type with bottom bracket plate adapter: older style mtb front derailleur mounted to a plate held by the bottom bracket cup)
Swing/action:
-top swing/low clamp: the derailleur parallelogram swings above the main pivot, generally corresponding to a lower clamp position for a band-type derailleur
-down swing: more traditional style where the cage swings below the main pivot, generally placing the clamp band further up the seat tube
-side swing: instead of a vertical parallelogram, the parallelogram is horizontal; can be had in low, mid, or high clamp band configurations as well as direct mount.
Pull:
Top pull: cable must approach from the top of the derailleur
Down or bottom pull: the cable must approach from below the derailleur
Dual pull: the cable can approach from either above or below the derailleur
Side swing: side swing front derailleurs require the cable to enter from the front, usually with full-length housing along the downtube


Why does my vintage Shimano rear derailleur come with brake style cable housing? I got a NOS Shimano RD-6400  rear derailler and it came with cable housing that I usually see on brake cable housing with that thick wire coil inside. I always thought those aren't suitable for shifting because they are designed to compress under load. What's the deal here?

I assume that you have a friction shifter?  A friction shifter is one that does not click into an indexed position. You just adjust it until the derailleur is lined up where you want it.
Assuming this is the case, the brake cable housing is what you should be using because it was the stuff that was around when those derailleurs were designed.  The compressionless housing, which is what the indexed shifters of today need, came about specifically for those shifters.
If my assumption is wrong, and your shifting is indexed, someone put the wrong stuff on there.  If it is working for you I don't think you need to rush out and change it, but as soon as the shifting gives you trouble, you know why, and it is time to change it.


Strategy for safe spoke removal Let's say someone had a heavy, overly strong front wheel on their re-purposed mtb. 26" wheel, 36 spokes.

What would be a safe pattern to follow to remove between 6 and 12 spokes?

To weaken the wheel you really want to remove a multiple of 4 spokes, so you balance leading, trailing, left and right. Six would be tricky. If the rim is reasonably strong you should be able to remove 12 as 3 groups of four to give that Shimano-style gapped spoke pattern. You'll have a gap, obviously, but the wheel will still be somewhat evenly tensioned.

Ideally you'd rebuild the wheel with the missing spokes distributed as a missing pair from every 6 spoke positions, but that would probably be more work than you want to do. If the wheel isn't fairly new the chance of stuck spokes is high, and disturbing it makes it more likely you'll damage something.

If you're reasonably familiar with truing wheels I suggest backing everything off a turn, removing the spokes, then tightening it all up again. That will let you work the spokes into a reasonably even tension while keeping the wheel straight. Removing groups of spokes when everything is tight will cause odd stressing mid-process and the risk of pulling a nipple through the rim or taco'ing are higher.

But... you're only going to save 20-30 grams, when a lighter wheel will save more. I'd stick with the strong wheel and save/scrounge a light one.

Also, per the comments from Criggie and Daniel R Hicks, if you are cutting spokes remember that they are under tension and the cut parts can exit the wheel with some force. If you want to keep the wheel it's better to back the spokes off rather than cutting them when tight.


Rear derailleur does not shift down I'm working on a bike where the right shifter was not working and I replaced it. it's a 7 gear cassette and the problem now is that the rear derailleur would not shift down past 3. When I manually I moved it down it stays there. It does shift back up all the way to 7. Shift down and it stops a 3 even though the shifter keeps clicking couple more times.  Any ideas what is going on?

Detach the cable at the derailleur and see where the derailleur sits. If its not in line with the lowest cog you need to adjust the lower limit screw. This is usually marked with an L. Screw it out until the top jockey wheel of the derialleur is precisely in line with the smallest cog. Reattach the cable with shifter on gear 1. Then click up one gear. Adjust the tensioner on shifter and/or derailleur until jockey wheel is precisely in line with second cog.

Finally shift all the way to the top cog and screw the high limit screw until you just feel resistance. This stops the chain going too far and dropping into your wheel.


Physical limits for a fixie rider As fixie-biking is really trendy at the moment, i often see fixie riders 'skidding' and stopping their bike by blocking their backwheel.

As this only works by shifting the riders weight to the front of the wheel i recently wondered if there is a physical limit (like weight) where this braking method will not work anymore because the pressure on the back wheel is still to big to skid?

There are more factors involved. Gearing being a major one - it is much easier to skid on a 38x18 compared to a 50x14 which is more like a track ratio.
Other major factors include road surface, rider strength, dry/wet, tyre width, tread pattern, rubber compound and inflation.

Indeed, as others have mentioned additional weight might actually make it easier to skid given increased momentum and pedal resistance provided they shift their weight appropriately.

I would say there is no practical upper limit for rider weight but gearing and tyre characteristics (a really fat slick tyre with a big contact patch on dry tarmac) could prevent it. Nevertheless, skidding the rear wheel is an ineffective way to slow or stop your bike even if it is good fun.


Which parts of a wrecked bike would be OK to use or sell? A few months ago I was in an accident with a car on my way home from work (oncoming car turned left in front of me). My bike was severely damaged, the frame broke in two and the front wheel is bent enough to be un-usable.

However, many of the other parts, the shifters, derailers, brakes, etc. seem to be in good condition. I'm considering using some and selling others of these parts. Excluding the obviously damaged parts, are there any other parts that shouldn't be used/sold? I wouldn't want to use/sell bad parts and I would be selling these with full disclosure on where they came from and what they went through. Basically I'd like to know if there are any parts that are typically damaged with wrecks like this and what I should look for.

We have no way to know what may or may not have been damaged in the accident, especially without knowing details about the accident and the types of components on the bike. Some parts you likely won't be able to determine if they're still functional until you put them on a different bike and ride on them.

That said, you're not going to get much by selling a lot of those components piecemeal, especially with a disclaimer that it's been in an accident.

My recommendation? Scrap the bike for parts, and keep them around as spares for your next bike. Having a good supply of used parts on hand can be incredibly useful.


Measuring stem clamp / handlebar diameter I have a new-ish Bianchi Cortina hybrid that I'm trying to find suitable drop bars for, but I can't figure out the proper size to get. It seems like the bars mostly come in 25.4mm, 26mm and 31.8mm. But do you get this size from the bars, or from the stem clamp?

When I measure the bars on the outside of the clamp, it looks to be about 25.4. When I measure the space in the clamp itself it seems closer to 31.8. When I measure the bars directly under the clamp (where it fattens up a bit) it seems somewhere in between. Help?

Measure the handlebar itself, while unmounted from the bike, at the center most point of the bar. Use a digital or vernier scale caliper.

The bar from the 2009 Bianchi Cortina is a 25.4mm MTB handlebar, with about 2 inches of rise. I expect yours will be as well. Do not use a 26mm bar, although you can likely mount it on the stem, because the installation will damage it, and it will fail, probably at some future point when you are riding it.

If you want a drop bar, you will need a new stem as well as handlebar. 25.4mm road drop bars are rare or non existent, since 25.4mm was the mountain bike standard.

I hope that helps.


Camera alternatives for commuting (2014 version) After a few near misses by cars and two mates actually being hit I want to start using a camera for taping video footage.

These are my requirements:

Long battery life (3h+)
Inconspicuous (absolutely no fancy GoPro-stuff on top of my helmet)
Small & lightweight
Reasonably priced (< 200AUS / 150EUR / 200US)
Reasonable easy to use (with gloves, in the rain, ...)
Good enough quality / angle for footage, but no further HD++ requirements
Stylish

I'm aware of these questions (Recommendations for inconspicuous helmet-mounted video camera, What is a good camera arrangement for city riding?) from 2010 & 2012, but with camera technology advancing rapidly, most recommendations and discussions are outdated as of 2014. I thought about adding to them, but think starting from a clean slate it beneficial for everyone.

After a lot of internet research I think I boiled it down to a handlebar-based setup with one of following cameras (for people with a larger budget, this looks like an interesting comparison of mostly more expensive models):

Tachion MicroHD:

1: 2.5h - 3: 96g - 4: 200US - 6: HD/125° - 7: :(

Liquid Image Ego:

1: 2.0h - 3: 70g - 4: 200US - 6: HD/135° - 7: :/

DogCam HD2:

1: 1.5h - 3: 62g - 4: 250AUS - 6: HD/135° - 7: :)

Contour Roam2:

1: 2.5h - 3: 144g - 4: 275AUS - 6: HD/170° - 7: :)

Contour +2:

1: ???h - 3: 155g - 4: 450AUS - 6: HD/170° - 7: :)

Polaroid XS 100 (identical to cheaper Easypix xtasy?):

1: 3.0h - 3: 136g - 4: 170AUS - 6: HD/170° - 7: :/

Kaiser Baas X80 Action Cam

1: 2.5h - 3: ???g - 4: 150AUS - 6: HD/???° - 7: :/

To finally come to my questions:

Does anyone

have experience in that problem domain / with one these models?
know about further alternatives?

Will try to update the question with further information...

A few years ago we bought a pile of the sub-$20 "mini dv" cams off ebay and they work fine as safety cams. Finding a waterproof enclosure is effectively impossible, so I used a plastic bag. At ~$10 each losing one is no the end of the world. Sample video: vimeo.com/15050277. If you're experimenting, buying a couple of those might be a worthwhile start to see how much hassle they are and how much use you get out of the camera. (I no longer bother, but then I ride to Cooks River cycleway every day and only ~5km of actual roads)

One thing that I've become more aware of/irritated by recently is the difference between 60fps and slower frame rates. For a safety cam 15fps is fine, but if you want to use the video for anything, 30fps is hard to watch. And a lot of the 1080p cameras don't even do 720p60. So if you're going to spend $200+ on an "HD" camera, try to get one that does a decent frame rate. That way when you start playing with the video you wan't get too grumpy. If you shoot at 1080p60 you can usually get software-stabilised 720p60 out of it, or you can pay a bit extra and get the stabilised Sony action cam instead.


Cranksets for tandem with internal gear hub I am thinking about assembling a trekking tandem bike. I would like to use an internal gear hub and put both chains on the right side of the bike. I have some questions about the cranksets:

What cranksets can I use? Can I replace the sprockets on any crankset with bigger ones (I would need two same-sized sprockets on the middle crankset)? Or do I need some specific type of a crankset?
How important is it to line up the chains in this case? What can I use to line the sprockets in the right position?
Is it possible to to use different size of sprockets for the front chain to compensate for the difference in strength between two cyclists, or will it make riding too hard because of the shifting phases?

You can use whatever cranksets you like and have available.  But tandems need either an eccentric bottom bracket on the front, OR a chain tensioner in order to set the tension on the link/timimg chain.

1.1. If you are only pootling around on the flat then perhaps the loss of the front chainring is acceptable.  But any hills or a good stiff headwind and you'll be regretting the loss of lower gears.  You might be able to offset this with a large rear cassette, a 42 tooth megarange or similar.

Chain line is important - the timing chain is often a 1/8th inch chain because it doesn't need any side flex.  The rear chain is often a normal 3/32" bicycle chain so it can be used with a derailleur.  You could use either (or even a drive belt!) To line up the chainrings, I'd use a long steel ruler, and try to use a matched pair of  chainrings and bottom bracket axles.

2.1. Since you have no front derailers, you could possibly flip the chainrings to have the big one close to the frame, and teh timing chain on the outside.  Or you could even have both chainrings the same size.   Its also possible, (but uncommon) to have just one big long chain doing all the drive.

No - the rider's pedalling should be in phase at all times.  If one rider is ready for a corner, there's a non-zero chance of pedal strike for the other rider.  This is doubly bad on a tandem.

If you want one rider to have an easier time of it, look for different length cranks.  They'll still have to do the same cadence as the other rider.

Suggestions:

Get a matched pair of doubles or triple chainrings.  Set your timing chain on the big ring, and use the stoker's middle/smaller ring for the normal chain.  If its too low geared, swap the timing chain to the middle and put the rear wheel chain on the big chainring.

Once you've settled on a good combination, you could remove the chainrings you're not using.

If you're building this tandem from scratch, separate the IGH hub purchase from the build.