Bike seems less stable when using handlebar bag On a recent 3 week trip I used a handlebar bag (together with two back bags) to carry the stuff I needed.
In the handlebar bag I carried a reflex camera, my phone, a power bank and some candy.

While my bike normally feels really stable, the first few days with the handlebar bag were a nightmare: the handlebar constantly felt really wobbly, to the point I had to check it was not loose. Then I got used to the feeling, but still could not completely trust the bike.

Can the handlebar bag cause such behaviour, and how can I mitigate it?

Edit: I had a picture of the handlebar bag to give an idea of the dimension. About the mounting, the bag itself is firmly held on the handlebar, and also the content did not have much clearance to move inside, maybe less than a centimeter. The reflex bag basically left only the space for the smartphone.

Yes, the bag can cause the instability. The physics is quite simple.

Ordinarily, a bike is self-stabilizing. If you turn the handlebars to the left, you steer to the left and the bike leans to the left. However, the turning gives a centrifugal force to the right, which causes the bike to want to lean to the right which, in turn, straightens it out.

With a bag on the handlebars, things change. With the bike perfectly upright, the weight of the bag acts completely downwards and does nothing to turn the handlebars. However, as the bike leans to the left, the bag can lower itself by turning the handlebars further to the left.  If the bag is heavy enough, this effect will overcome the self-righting stability of the bike and now you have a system that responds to a slight turn to the left by trying to turn more sharply (positive feedback) rather than the usual situation of responding to a slight turn to the left by trying to go straight again (negative feedback). This is the instability that you felt while riding.


Putting a DH fork on an enduro bike: consequences? I am into downhill (DH) but I don't live 1) in a country with a lot of DH parks with lifting services etc 2) near such parks. Still I like riding rough stuff (in forests or in town) so that I would finally opt for an enduro bike.

Concretely: I initially planned to buy a DH bike, the Commencal Supreme DH 29 signature 2019 and finally I will end up buying an enduro bike, the Commencal meta AM 29 Signature 2019.

But, I would like to replace the fork of the enduro bike with the one from the DH bike.

Is this a good idea, as it would affect the geometry of the bike?

How would this specifically affect the bike? Would it affect pedaling a lot so that at the end I wouldn't be able to use it for enduro (flat + uphill pedaling) as efficiently? What would be other effects?

Let us assume that the wheel size stays the same at 29". Let us also assume that a DH fork can be installed on that frame with no clearance or mounting issues. What remains are questions of frame geometry and safety.

  How would this specifically affect the bike?

I would say that the main parameter that changes is fork's axle to crown distance. DH forks have more travel than enduro: let's say 200 mm against 170 mm that the bike you link to has. So the top of the bike gets raised up for 30 mm. Each 10 mm of change corresponds roughly to 0,5° decrease of head tube angle. So that makes it 1,5° or more. It means the whole front end would raise up; if you stand on a perfectly horizontal surface, with a new fork it would feel as if you ride 1,5° uphill. Needless to say such a change won't help you climbing up hills, but exactly the opposite.

1,5° is a lot of a change for head tube angle, which becomes 64°. Most likely you will find it harder to make turns or to control your bike in turns.

Bottom bracket would be raised as well, possibly making the bike unstable in controlling, see this answer. Less pedal strikes, however.

  What would be other effects?

It would weigh more, and it would not be covered by vendor's guarantee any longer because using a longer travel fork certainly voids it. Remember that an enduro bike frame and remaining components, such as handlebar and wheels, were designed, tested and certified for certain types of drop heights. Downhill riding assumes harsher loads; you would not want your handlebar to snap.

  Is this a good idea?

No it is not.


Is the Suunto Ambit compatible with the Bontrager DuoTrap Digital Speed/Cadence Sensor? Bontrager DuoTrap is ANT+ compatible as well as the Suunto Ambit (with firmare 2.0 or greater).

Since it's not possible to find any proof of concept on the internet (specialized sites, forums, etc...) about the compatibility of these two devices, is it possible to know of some of you guys got this working?

Definitely YES.

It works both with speed and cadence!
I paired the "bike pod" and got both the two measurement. At first I tried to pair also the "cadence pod" without success and I thought it wasn't working but then I took a ride and found out that the cadence was showing!


French handlebar fit I have an Atax stem ('85 Peugeot). Original steel handlebars are 25 mm.

Is it prudent to spread the stem to accommodate  Nitto 25.4 randonneur bars?

I wouldn't try it.

70's french stems aren't trustworthy, 80's don't seem much better and weakening a stem isn't exactly worth the risk anyway (I'd opt for sanding it rather than spreading it to remove the necessary material instead if I had to, but I'd recommend getting a new stem instead). You'll probably scratch up your nice new bars too.

Try to get the current stem out and replace it. If not going to come out, you may want to try sanding it, but I'd recommend just living with the existing bars.


What benefits in bikes like "trek", "cannondale", over "merida" and such? There are more expensive marks like "Trek", "Cannondale", "Specialized" and cheaper ones like "Merida", "Norco" and many others.
What are the benefits of the expensive ones, if say the components like frame material, derailleurs, brakes, BB, cassettes, rims, tires are the same?

You're paying some amount for the branding of the bike, as well as the bike shop to carry the branding and advertising it and supporting the bike after you buy it. A lot of components can be the same - for example, tons of major brand and non-major brand run complete Shimano 105 drivetrains and various other parts (they may have slight model number changes for OEM versions versus retail versions, but essentially the same stuff).

However, there can be some engineering differences though in the parts which are intrinsically the manufacturer's. This is typically the frame+fork - just because you make two frames which look kinda alike out of the same material doesn't mean that they are the same quality frames, or as well engineered as each other for lightness/strength/stability/etc. [Though I'm not saying that smaller branded products are necessarily worse-ly engineered. ]

Also, typically, the major brand stuff looks a lot nicer with better resale value if you're into that sort of thing.

It is worth saying that while some places (e.g. BikesDirect) advertise a lot of their frames as "compare to (name brand) at (much higher price)", there are trade-offs in what you get. The frame, for example, may have less nice joins, be a bit heavier, use a lower grade of metal, etc. , so its not exactly the same thing (in some cases, good enough, in other cases, a poor imitation). A lot of people often play the argument that all these bikes are made in similar factories in Taiwan or whatever, but they aren't (usually) coming from the same molds, and a factory can produce a decent spectrum of qualities and types of bikes. [Another thing to note is that places like BD don't have the overhead of a retail shop where  you may get a bike fit or having to hire people to stand in line and what not]

(Unlike in the car world, I don't believe that bicycles are often badge engineered anymore (Schwinn had a bunch in the 70s and 80s for the non-made in USA stuff). But you can get some good bikes from some brands which are cheaper than others.)

As for the price difference, a lot is knowing when to buy - if you buy at the right point in time, the price difference is a lot smaller than usual.


Replacing a rear wheel bicycle axle. How should I do it? I bought a second hand bike a few weeks ago.. sadly the rear wheel axle broke. I want to replace it, but since the bike is a little old (maybe 30 years old. it's a monark, a swedish known brand) I'm not sure if that's possible.
Also, I've never done this before, so it's not very obvious what should be done.

Since I moved here a month and a half ago and don't really have any available tools.. can I get away with only a wrench and/or a cone wrench? what else is needed?
I bought a new axle from a shady shop where the dude told me that if it doesn't fit he can exchange it for something else.. but I'm not very confident about this.

here are some pics:

What do you think?
Thanks!

Generally speaking, you'll need to remove the cassette/freewheel/block in order to get access to both sides of the wheel.

Your photo shows no bearings - its not impossible they're still in the wheel?

Suggestion - Clean the whole wheel first. Dirty stuff makes any job harder.  That rim looks pretty bad.

There's a good chance you can transfer most of the nuts and spacers over, keeping the same order as in your photo.  Depending on wear of the cone's bearing surface, you might use the new or old one.

Clean out all the old grease/lube from the wheel's bearing races (the cups)  Use a solvent and those paper towels to make it clean.

Then put in some grease, and use it as a "mortar" to hold the bearings in place around the raceway.

Tools You need a cone spanner and a regular spanner, to tighten the cone against the locknut and hold it in position.  You will require grease for the bearings, and its always a good idea to fit new bearings while its all open.  The old ones might look okay but bearings are real cheap, $3-$10 a wheel.

Endgame is to have your hub assembled like this: - yours is 99% a freehub so will look like the lower photo.

Your axle broke because of the loading - notice how the ball bearings (red) are not very far out-board on the freewheel compared to the freehub?  This means the axle is under a continual bending stress near where it fractured.  There's a chance your new axle will do the same over time,  which is why freewheel designs are relegated to the cheap end nowdays and are gone from most bikes.

Still it'll be totally rideable with a new axle.


Shimano Deore FD-M590 replacement I need a new front derailleur.  I have a Shimano Deore FD-M590, but am rather disappointed in it.  It's only three years old and won't advance the chain to the biggest ring.  Bike shop guy said I need a new one.  I'm never had a derailler go bad that fast.  Does anyone have a suggestion for a replacement.

Did you try adjusting it yourself? http://www.parktool.com/blog/repair-help/front-derailleur-adjustment

Did you rule out the shifter/cable/cable housing causing problems? Try manipulating the cable tension by hand to shift it to see if this is the case and then work from the problem if it doesn't let you move the cage with reasonable cable manipulation.

If it doesn't adjust and the shifter is good, I'd just replace it with the same thing that is already on there (note that you need to get the right clamp and cable pull type for your frame, so you might as well order it from the bike shop if you don't know what clamp type and what not you need).

FD's are relatively simple parts that don't have a wide range of performance between grades, and its just about as cheap for what you have as with the lower group parts.


Modifying a bike for winter (on a budget) I have two bikes, a hybrid commuter with skinny tyres, full mud guards & rim brakes, then I have a 29er hardtail MTB with hydraulic disc brakes and off road tyres. Which would be best, for commuting (with a minimum modification cost) in the snow? (this is likeley to be a small-medium amount of snow, perhaps having been compressed by other vehicles/walkers)

Having lived in a few parts of the US, I've found what people call small to medium to be drastically different based on the region ("oh yeah, we just had a light snow last night", and i look outside to see 4+ inches versus "it snowed like crazy last night" and i look outside to see a half inch and the whole city has come to a grinding halt), so its a bit hard to judge how much snow you're going to encounter, so I'm going to assume 2-3 inches fairly regularly (if it snows once or twice in the winter where you live, who cares?).

The ideal winter bike should be cheap and preferably somewhat disposable. Full fenders are good since they'll protect you from slush and what not and your drivetrain. The slush and snow and grit will still get into your drivetrain and what not even with full fenders, so you do have to make a habit of cleaning the bike off regularly in the winter (which can be tricky depending on where you live), or component life can be drastically shortened.

If you expect to encounter ice, studded tires are advisable (Peter White's page is an OK overview for this: http://www.peterwhitecycles.com/studdedtires.asp , though Nashbar does (used to?) sell very cheap studded tires made by Kenda - not good for off road, but perfect for commuting). I'd say have these on hand if you can - in my experience, snow often leads to ice. Just don't try riding like a maniac or you're wear out the studs. If you can't afford them, get a cheap set of knobbies and run them at low pressure and be careful (always be careful when theres snow+ice around). Be careful with sizing since studded tires of the same "size" may need slightly different clearance.

As for the hybrid, it depends on what kind of hybrid it is - if it isn't twitchy and can use "large" tires (say, like a Trek 7.2 fx or a modern Specialized Sirrus), it should be OK. If not, I'd use the mountain bike and try to fit some fenders on it (probably you'll be only to fit things like the SKS X-tra dry, X-board or something similar, but its better than nothing) and take extra care to clean it up regularly. Discs would be nice for winter commuting at times if your rims are covered in slush, but a good V or canti setup is fine as well. Overall, if you have to use one of your two current bikes and both fit the conditions above, use the cheaper one or the one you're more comfortable riding in messy situations.

The best option IMO is to find a cheap old rigid (one less thing to go wrong - some of the cheaper suspension bikes make horrible noises in the winter and its just not necessary) mountain bike (think 90s specialized hardrock, giant boulder (I've use a 2003-ish one of these as my commuter for the past few years, since its fairly comfortable, pretty cheap to maintain (though things rarely fail, even with cheap (acera-x level) components), fits full fenders and a rack, fits reasonable sized tires and nobody wants to steal it!) or whatever - the spec, weight is far less important for a beater than for your primary bike, just a decent fit) probably at Goodwill or something (these are quite cheap to find about now - if you live near a college campus and go to a bike shop which sells more cheaper / used bikes, you'll be able to select some from there at a bit of a higher but reasonable price), give it some elbow grease (probably a new chain and lube and new brake pads, some various adjustments), fit it with full fenders, some lights (extremely important in winter) and some knobby/studded tires. Replace components as they start being not good. The total cost for this could be less than 100 dollars and two - three hours of work if you're smart about it and prone to getting distracted (so you can then invest in some winter clothing!).


Smart trainer & CX bike compatibility I have a Kona Jake the Snake Frame (2001) and is currently mounted with Continental Gatorskin 700x32c tires and Shimano RS010 622x15c rims. I was hoping to use this on a smart trainer. This setup will be used for software like Rouvy. I'm new to cycling and was hoping someone could help me with some questions:

1.) Is it safe to mount thinner tires on the bike? If so, how thin can I go.

2.) Will the weight of the bike be an issue in choosing a smart trainer?

3.) I'm currently interested in buying a Tacx Bushido since I found a cheap one on chainreactioncycles. On the Tacx website, it says that as long as you use their Tacx 29" trainer tire, you can fit the bike on the trainer. Did I understand this correctly?

I will try to answer as best i can without going into too much detail,

1 : With a 15c rim you can mount 23, 25, 28 and 32 tires Sheldon brown Tire Sizing

2 : Bike weight, Tacx don't specifically list any info regarding bike weight, as the user of the bike on the trainer can vary, I doubt this will be issue unless we're talking excessive weight.

3 : Tacx recommend the use of their tire as it has been designed to run without overheating, a quick search on the Tacx website has the 4 different sizes listed for 40 euros (Doesn't sound to bad to be fair) Tacx Tires

Hopefully this helps you out.


Flat tire keeps occurring while bike is stationary. MYSTERY I keep changing my tube. It get's a hole right near the base of the valve. I've checked the rim, there's nothing sharp. there's nothing sharp in the tire (the hole's on the inside anyhow). and it always happens while just sitting in my garage not while riding and bumping into rocks or such. all of a sudden from what I cannot determine you hear a hissing sound as air starts escaping. The tube was pumped with ~75 psi about 2 weeks ago, and the tire says max 80, min 50. the rim tape is intact.

Please suggest what could be causing these flat tires, why is there a delay from when I stop riding it and 8 hours later between getting a flat.

I had a similar problem on my bike. The manufacturer had made the rims too deep and it was causing the tube to conform to the odd extra "U" shape when pumped up. It took a while to figure out why I was going through so many tubes.

Check with your manufacturer / retailer. I got mine replaced free of charge.

Perhaps your rims have an abnormality near the valve hole.


Raleigh Nitro MTB - 5-7 speed freewheel conversion - 135mm spacing I have a Raleigh Nitro Mountain Bike that I want to convert from a 5 to a 7 speed freewheel. The rear drop-out spacing is 135mm.

Am I right in thinking that all I need to do is get a rear wheel that is 135mm with a 7 speed freewheel? (And obviously upgrade the shifter and rear derailleur.)  Am I missing anything obvious?

Many thanks in advance.

You may not have to get a whole rear wheel, you may be able to just replace the freewheel with a 7 speed unit, depending in how much room there is for the wider freewheel. Maybe you will need to add spacers to the drive side and re-dish the wheel to make room.

Five speed freewheel systems were originally used with 120mm drop-out spacing. To get more speeds drop-out spacing increased to 130mm with 8 sprockets but this made the axles prone to break or bend.

If you are going to replace the whole wheel, get one with a modern freehub and 7 speed cassette, instead of the older and much weaker freewheel system.


2014 Diamondback Jr. Viper Brake Problem BIKE

2014 Diamondback Jr. Viper

SPECS

Specification            Description
---------------------------------------------------
Best use                 Cycling
Bike style               BMX bike
Bike frame material      Steel
Frame                    DB high-tensile steel
Bike suspension          No suspension
Fork                     BMX high-tensile steel
Crankset                 1-piece steel, 36t
Bottom bracket           Loose ball
Rear cogs                18t freewheel
Brake type               Coaster brake
Brakes                   Rush V-brake
Brake levers             Rush RX2.1
Rims                     Alloy
Front hub                Steel, 36h
Rear hub                 Steel, 36h
Wheel size               20 inches
Tires                    Comp III Style, 20x1.75
Handlebar shape          BMX bar
Handlebar                Steel BMX
Stem                     Alloy quill
Seat post                Steel pillar
Saddle                   DB BMX Padded
Pedals                   Resin platform
Headset                  Threaded steel
Chain                    KMC Z410

PROBLEM

The brakes on the handlebar are really hard to pull and make a popping noise when you pull all the way in. Also, when you just roll the bike, it feels like as it rolls, the brakes are being applied.  We've already taken the bike back to REI to have them adjust the brakes and/or spokes on a truing stand.  I don't know what else to do or how to correct the situation.  We simply want the bike to be able to roll freely and have the brakes apply only when depressing the pedal or the handlebar brake.

This bike looks to have a vee brake seen on (now old school) mountain bikes.

The popping noise you notice could be the cable housing not sitting in one of its barrels. And, pulling the lever that could cause it to move suddenly in/out of place. It  could also explain why the wheel isn't turning well: the housing could pull on the cable, and hence the brake. Check the housing, if it keeps falling out of the those little barrels, it may be because the housing is excessively long. Have REI shorten it for you -- you can do it yourself, but you'll need something more than those needle noise pliers. ;)

If that's not it, check the wheel. Ensure it's sitting center in the frame. Lift the bike and turn the rear wheel, if the brake pads are really close to the rim, then you will want to give out a little slack to brake cable. If one pad rubs, adjust the amount each brake arm's spring pulls outward. (There should be a small screw on the side of each brake arm.) I like to balance the spring tension, so if you tighten one arm, loosen the opposing arm.

Hope that helps.


Can a non-cylindrical grip be better for jumping? I'm learning to jump my mountain bike.
I've noticed that when jumping, if I "death-grip" the handlebar, my hands can actually twist around the handlebar. This happens in both the ascending movement, and after impact when finishing the jump.
Such twisting feels sketchy so I'm inclined to avoid a death-grip.
But the alternative, namely placing the index fingers over the brake levers, while it gives me a better grip with no twisting, has the obvious danger of accidentally braking the bike as I land the jump. I don't deliberately brake the bike on landing, but it's easy to have that reflex.
So I was thinking, why not get a grip that is non-cylindrical? I've seen a few such models. They seem to be marketed as "ergonomic" grips.
An example would be the GP series from Ergon.
Is it a good idea to get non-cylindrical grip for jumping? Should I get a better technique instead?

With good grips, your hands should stay pretty much planted in place. Since grips are relatively cheap (you can get a decent pair of lock-ons for $7). It is not recommended to "death grip" your handlebars when mountain biking as it increases the amount of shock that goes into your wrists, rather you should hold them with enough force that you are still holding on but loose enough that you can turn them slightly to absorb shock. One thing that may help as well is to make sure that your thumbs are on the underside of the grip, not parallel with the rest of your fingers.
As for non-cylindrical grips, that is probably not the solution. You will notice that most professionals use cylindrical grips, because non-cylindrical grips change the way you are connected to the bike, your posture, and in general negatively impact your control on rough terrain, especially jumps.
As a final word, if you are having trouble keeping your hands in one place, check to see if your grips are good enough (you may want to swap them out with some higher quality ones). In general, wearing gloves can improve grip but many people do not wear them so it is not a necessity.


Can I 'upgrade' a 9 speed Tiagra RD to Sora to lower my gears? My girlfriend has an oldish Cannondale CAAD8 bike with Tiagra 9 speed triple. The rear derailleur is the RD-4500 GS with a 12-26 cassette. The front is a 50-39-30. She'd like to get a lower bottom gear as we plan on touring up some intimidating hills this summer... The issue is that the RD-4500 doesn't support larger than a 27 tooth sprocket at the back.
Would we be able to switch the RD-4500 for the Sora RD-R3000 GS? My hope is that it's 9 speed, so should be compatible. It has a much wider size (supporting up to a 34T at the back, total capacity of 43), whilst still supporting front chainring difference of 20.
I would then throw on a 11-34 cassette or something like that, changing the chain at the same time.
Is she likely to run into any issues? Is current-Sora worse or better than 15-year-old Tiagra in terms of smoothness etc. (though of course she'll lose out on some smoothness by widening the cassette)?
Is there anything else I should be checking - or any other good ways to achieve a similar range of gears? (She doesn't care too much about the fastest gears, rarely finds herself in them so if you have any options that involve sacrificing a bit of room at that end please go for it.) We're thinking about this option because at least she won't have to upgrade to 10 speed and change all the shifters, etc.

You have several options depending what is important to her, I am presuming cost is a factor.
11-34 cassette with new derailleur and chain (given cassettes and chains are consumable) is cost effective, but it does mean the jump between gear changes increases.  If she does not need the higher gears then there are ways to bodge a cassette of say 14-34 that would close the gap (at the risk ramps would not line up making shifting less smooth)
Decreasing the chain rings from 30, as commonly suggested, means to to get the same ratio as 30/34 would require a 23/26 (reality 22 or 24)  chainring, which almost certainly won't work with the existing derailleur and frame, and if it did, would also require new cranks, i.e. not cost effective.
A hybrid solution of a smaller chainring and larger, but not as large as 34 cassette, adds the cost of a chain ring but reduces the jump between gears, but allows you to tert some things before spending money that may not be needed  This could be done in steps-try say 11-30 cassette with existing derailleur (see comments - pushing it, but should work acceptably), if that works, but low gear is still to high, smaller chainring. If shifting is unacceptable, upgrade derailleur.
A final option would be go to a 10 or 11 Speed rear. If you are already upgrading the derailleur, cassette and chain, it adds just the cost of a shifter (and cable inner).  10 and 11 speed will play acceptably with a 9speed front end and the wide range cassette means front shifting is reduced anyway.  Obviously the decision to do this needs to be done before purchase.


How to check and ensure parallelism of front derailer and chainrings? Various instructions of front derailers with clamp want me to ensure that the derailer cage is parallel to the chainrings.
What is the preferred way to do this?
Since the derailer cage has quite a complex three dimensional shape I'm not entirely sure which lines to use as guides.
Should I use the inner side of the outer plate?
Do you look from above or from behind?
I'm looking for some best practices.

It depends on the derailleur.
Most or perhaps all Shimano FDs intend to have you use the top forward part of the outside cage as your reference surface. Where the logo is. Their published procedures show this. This is especially true of the knuckle type road models of the last few years.
SRAM Yaw FDs have you use the marked lines down the center of the cage in the back and front while looking down. Other SRAM ones use the same forward top surface.
Sometimes you don't know and have to intuit it. Usually you should avoid looking at the inside cage as your surface because it's typically stamped and manipulated all over the place. There are of course FDs, usually older, where the sides of the cage are parallel, but usually those are easy to align. (They're the sort most likely for you to need to angle the cage.)


Campy 11 speed and Shimano compatibility Two part question.

Is it possible to run Chorus, Record or Super Record 11 speed disc mechanical brake/shifters with Ultegra R8000 11 speed derailleurs?

I can use either campy or Shimano wheels and cassettes.

Are Campy brake levers going to work with Ultegra disk brake?

Thank you.

Derailleurs: No. Shimano and Campagnolo derailleurs have different actuation ratios, and while there are adapters for many other combinations, Shimano to Campagnolo 11-speed isn't manufactured. The cassettes are so close that you can use cassette from one 11-speed system with the other, so there's less need to mix derailleur brands.

Mechanical brakes: Yes, but not optimal. Newer Shimano road brakes use slightly more cable movement for the same brake actuation, so Campagnolo levers will work with them but feel spongy and if you don't keep the brakes well adjusted the levers may hit handlebars before maximum braking power.

Hydraulic brakes: From what I could find, both brands use 22mm pistons, 5mm hoses and mineral oil based brake fluid, so they are not fundamentally incompatible. I wouldn't try it myself, since brakes are the one component you don't want to fail.

Edit: Regarding the other answer, the fluid transfer amount is determined only by piston cross section area. Shimano and Campagnolo road brakes apparently have similar sized pistons, but this doesn't apply MTB models, different brands and future models. The fittings are different, but since hose size is same, you should be able to install fitting from different brand on one end. I still wouldn't do this and shifting wouldn't still work.


Converting triple crank to single or double I got triple crank (44-32-22) and 3x9 speed drivetrain. What will I need and is it possible to remove some of the chainrings and convert the crank to single or double?
Will I need new parts or adjustements?
Thank you in advance! :)

At the simplest level you may simply be able to unbolt a chainring and re-set the limit screws on the front derailleur to stop it shifting onto the missing chainring. I assume you're trying to remove the smallest chainring, and those are fairly commonly removable even on cheaper setups. Slightly more expensive setups will have all chainrings removable, so you could remove two chainrings.

If you can't do that it's probable that your bike is so cheap that buying parts for it is a waste of money - while you can buy cheap parts the markup and distribution costs mean you're not saving much over the cost of a better part. But spending $100 on a new crankset for a $300 bike doesn't usually make sense.

What you will probably find is that even with a single chainring you still need the front derailleur to stop the chain falling off. Derailleur systems are designed in many ways to facilitate that, only they call it "changing gear". If you look at many of the 1xN setups on the market they have a chain retention device that does the same thing.

If you just want to find out whether you can deal with only having one chainring, I suggest simply not shifting gears on the front derailleur. See how you go, if you regularly find yourself having to either shift it or get off the bike, a single chainring setup will probably not work for you.


Affordable trainers for winter conditioning I've just bought a 2018 Specialized diverge with 30mm tires. I'd like to purchase an affordable and efficient trainer that won't cost me too many bananas. Any recommendations? I've perused amazon and there are some best sellers with decent reviews but I can't seem to see if they'll accommodate my tire size size.

Thanks in advance for your help!

All trainers are adjustable and will work with a wide range or tire sizes and wheel diameters.

Efficiency isn't a concern with trainer because their function is actually to be completely inefficient i.e. to make you do work, soak up your energy output and turn it into heat. Low noise, adjustability, and  'feel' are what you are looking for.

If you want affordable, look on Craiglist or an equivalent bike and gear used marketplace where you located. Where I am there seems to be many to choose from. People buy them, don't get into indoor training then look to sell them on.

Make sure you get a trainer than is compatible with your rear wheel, attachment - quick release or through axle. Be aware than cheaper trainers that clamp onto the quick release skewer can chew it up, so consider getting a cheap or used sacrificial one.


Mix Match Using Wolftooth Tanpan My current setup are using a full Shimano 105, medium cage GS 11-34t, crank are 50-34t. Through some digging, I want to upgrade the RD using Deore XT M8000 SGS Long, paired using wolftooth tanpan.
Based on tanpan product specification, it should work with 2 chainring setup with 11-42t sprocket. But I'm not sure. Is there anyone having experience doing this? Do I need change the crank to lower setup, a 46-30t?

According to the Deore XT RD-M8000-SGS Long specs it should work (you are right at the limit though, but they are known to be conservative). No need to change the crank/chainrings (but you can if you want to).


Rohloff clicking sound with ratchety feeling Recently, my Rohloff-geared bicycle started to make a regular clicking sound with a ratchety feeling associated with it. Besides a click, I feel a small resistance transmitted through the pedals. This is the same click that I always feel (have been from the start) when I'm stationary, put weight on the pedals, and change gears. But now I get it at a regular interval when riding; it happens every couple of turns of the pedals. I think it's coming from my Rohloff hub. My hub is a bit more than 3 years old, and I've done 12000 km with it. My last oil change was less than 2 months ago. The only component I have replaced since the bicycle was new was the bottom bracket, which failed last winter so which is now new.

I would bring it along the bikestore for a specialist to have a look at it, but the nearest specialist is 1600 km (1000 mi) away, shipping the bicycle back and forth would cost hundreds of euros. I'm slightly worried that, if it is related to the hub, I might be damaging it by continuing to ride on it. At my last oil change I spilt a little bit of oil, but I'm pretty sure most of the oil went in, so the oil should be sufficient. Should I do another oil change, just to be sure and just to see if it gets rid of the clicking sound? Or is it more likely to be caused by another factor?

Possibly related questions here, here.

I have a Rohloff and have sent some emails to the factory due to severe oil spill (had to replace the seals, successfully). From what they have told me, the 25ml of oil is more than double the necessary amount for the hub to work fine, since the oil is very sticky and it distributes inside the hub. Even the unavoidable oil "sweating" should be considered normal, they say.

Recently, I hosted a rider which had a very heavy bike, with 40.000+ on the bike, going to Patagonia (South America). He ultimately LOCKED the hub, being only able to push the bike, not pedal forward or backwards. Rohloff replaced the hub for free, but he had to travel to the capital 1600km away to receive the package :o(

I doubt very much that lack/excess of oil is the problem. I agree with what folks are saying about the chain/sprocket (either too tight or otherwise defective, with a frozen link, or a bent chainring tooth).

What I suggest you is to isolate the drivetrain from the problem: be sure the chainring, chain, sprocket and chaintensioner (if any) are not generating the click.

If not so, write to Rohloff describing your problem as thoroughly as possible, they are VERY supportive.

The not-so-good news is that Rohloff, besides being a marvel of engineering indeed, is not as nearly as bomb-proof as a lot of fanboys tend to propagate, if it is used hard for a long time, some part replacements are unavoidable.

And even with Rohloff, some defects can appear, and the exact building of the hub has changed over the years to avoid common patterns of failure detected.

Unfortunately, it is not possible to be sure if the hub is defective or not, at least via this site, but I hope this helps. Any question in the comments, and I'll be ready to answer.


Which cleats provide more adjustment freedom? Currently I have MTB shoes and I am surprised how little freedom they provide for left-right adjustment (shift). So I wonder which cleats -- MTB vs road -- provide more adjustment freedom?

Assuming such question can be answered in general (i.e. without ton of exceptions that brand X provide more than Y).

Update there is more than one way to skin the cat -- by adjustment I meant fixing the cleat on the shoe with screws. Not the adjustment when on the bike and small movements which pedal+cleat allow.

All brands and type of cleats offer some left/right floating freedom.

Regular Shimano SPD have a lot of freedom.

Shimano and Looks cleats have different cleats to allow different range of left/right floats.

Shimano SPD-SL Pedal Cleats

Red 0° Float
Blue 2° Float (provided with high-end e.g. Dura Ace SPD-SL pedals)
Yellow 6° Float (provided with most Shimano SPD-SL pedals)

Look Pedal Cleats

Black 0° Float
Grey 4.5° Float
Red 9° Float

Have a looksie here for more pedals and cleats info.


Derailleur-shifters compatibility Shimano GRX Shimano writes in the description of the Shimano GRX Shadow Plus RD-RX812 11-speed rear derailleur that it is compatible with shifters GRX ST-RX810 and ST-RX600 shift/brake levers.
Should I understand that it is "only" with these shifters because of a pulling ratio different from their road but also from their MTB standard? An information that I can't find anywhere. Or is the derailleur a standard road one compatible with their road shifters?

The rear pull ratios used by Shimano are:

SIS v1 for Dura-Ace 7400 only, which was about 1mm cable to 1.9mm derailleur movement
SIS v2 for everything excluding that, up to the introduction of 10-speed MTB (i.e. including 10-speed road, which came before 10sp MTB), which was about 1:1.7
Dynasys / 'New MTB' - which was introduced for 10-speed MTB and kept for 11 & 12-speed, which is about 1:1.2
'New Road', which was introduced for Shimano 11-speed road, and subsequently used for all 10-speed road (which includes gravel) products introduced since the introduction of that, which is about 1:1.4

Essentially with ever more closely spaced sprockets, it emerged that while pulling less cable means a shift requires more force, it makes shifting more accurate/precise/easier to setup. Hence after the introduction of 10-speed MTB which pulls more cable per shift, and the introduction of hidden cabling for second-generation 10-speed road, which adds more right-angles/friction, Shimano came up with an intermediate shift ratio between MTB and the previous standard. Since the old ratio didn't work that well with hidden cabling & 10-speeds or more, they essentially have one standard that is used for all new 10 & 11-speed, and probably will be kept for 12-speeds as well.
So the RX812 is not '11-speed', since the RD is not indexed. It will work with shifters that use Shimano's new road pull ratio, which is anything GRX (10 or 11-speed), anything 11-speed, and Tiagra 4700 10-speed.
There are some older 10-speed road shifters using the standard-for-everything-for-a-quarter-of-a-century-pull ratio, but they are no longer in the Shimano range.
The thing specifically with RD-RX812 is it's marked for a 1x drivetrain, and Shimano don't have 1x levers for road (only for gravel), so they only show it compatible with the GRX levers, since these have brake-only levers. There's however nothing stopping you using it with, say, SL-4700-R, which is a flat bar 10-speed lever, and a Deore 10-speed 11-42 cassette.


Hybrid bike stolen, trying to weigh factors for how to replace I had my 2006 Trek 3700 stolen from my apartment today. I reported it to the police and should be getting at least a small amount of money from renter's insurance. It was locked with a Kryptonite combination cable lock to my front porch. They did not cut the rails of the porch, and the lock was not there anymore. My conclusion is that either they figured out the combination somehow or cut the lock. I use my bike to commute to work (about 15 min. bike ride on a community bike path), so I need to replace it ASAP. I'm trying to weigh a few factors:

-I don't want to spend too much money on it, for a couple reasons. One, I don't want to attract more thieves when I have to lock it up, though I'll try to bring it inside more and get a better lock. Two, my bike that I paid $270 for in 2006 has served me just fine.

-I'm not comfortable buying a used bike.

-My previous bike was very heavy, and I live on the second floor, so a lighter weight bike would enable me to store in my apartment (and at my office) rather than locking it up on the porch or bike racks at work. I realize this would probably cost more, though, and contradicts the "avoiding theft" when I do have to lock it up to meet people elsewhere.

-While a lighter bike would allow me to keep it safer from theft, I did prefer the mountain bike style of not having drop handles, and I like the shock absorption of all the potholes we get on the east coast, and mountain bikes (or even hybrid bikes) are heavier.

Are there any lighter weight mid-price-range hybrid bikes that you could recommend? Or something else that balances my above concerns?

Thanks so much.

I know you say you're not comfortable buying a used bike, but…

A used bike will get you so much closer to what you say you want in a bike, and can be so much better a value for your money. Here's my pitch for a used bike:

Look for a brand name "vintage" mountain bike – one without suspension, but with tons of clearance for fenders and wide tires. If I were looking, I be hunting for something like a Trek 850 from the '90s. I think Bridgestone also made some nice bikes of similar vintage.
The wide tires will let you run wide street tires (something like a Schwalbe Big Apple) at a relatively low pressure that will give you a comfortable ride with relatively low rolling resistance.
No suspension means lower weight, complexity, and for equivalent quality lower cost. Eliminating the suspension also makes it easier to fit fenders and racks.
An old used bike will have lower perceived value, especially a steel bike with skinny tubes. Steel is nice in a used bike because it is much less likely to fail suddenly as a result of mistreatment by a former owner and it is also out of vogue which may help with the thieves.

So the big question, I think, is why not a used bike?

If it's because you don't feel qualified to check out a used bike, I can understand that. Perhaps your LBS sells used bikes, or can recommend someone who refurbishes them in your area. I'd also encourage you to consider that bikes aren't like cars. They are much closer to "what you see is what you get." If you test ride the bike and like it and all of the basic functions work – brakes, shifting, adjusting the seat and bars – then you're probably good. You could also factor in the cost of having your LBS do a tune up.


What MTB 10 speed double cranksets exist with 180mm cranks? I am looking for a a 10 speed dual crankset that has 180mm cranks.

I see the SRAM cranksets only come in 170 and 175mm.

http://bike.shimano.com/publish/content/global_cycle/en/us/index/products/mountain/new_xtr/component_systems/race.html#drivetrain/0001/FC-M985

Hopefully that links you to the XTR Race crankset. Double and available in 180mm.
Then new XT Dyna-sys cranksets, in triple, will also be available in 180mm.


What is the longest reasonable distance one may expect to ride on a comfort bike? I ride a 2011 Trek Navigator 1 with 7-speed derailleur.  Purchased in August of 2011, I've tried to ride as often as possible.  My longest rides have been approximately 12 miles in length.  I've equipped the bike with SKS fenders and a rear rack.  I'm getting to the point where I'd like to start taking longer rides, maybe 10 or miles each way.  Is this sort of riding unfeasible on a "comfort" bike?

I would argue that there is no limitation on distance the biggest limitation you will have will be on: Speed and Comfort over time.
Speed
Comfort bikes arn't made to go fast.  They are designed to be ridden around in a leisurely way.  Variables limiting speed include:

Aerodynamics - you are sitting as upright as possible
% of your speed/strength you can use while pedaling - Mountain bikes are designed so that the rider has good control and can soak up bumps.  Road bikes are designed to be maximally aerodynamic and to allow the rider to use their leg muscles effectively.  Comfort bikes are designed so that you will be comfortable sitting on the seat.  I have always found that when riding a comfort bike I cannot use my muscles nearly as effectively.  On a road or mountain bike it is much easier to use your upper body to provide leverage to your legs out of the saddle.
Weight - shouldn't have an effect on a constant speed but when speeding up you will notice the weight of your bike.  You will also notice the extra weight when climbing.  In all other situation weight shouldn't make any difference.

Comfort over time
Road bikes and to a lesser extent mountain bikes are made to be comfortable for long period of time for more dedicated riders.  Just looking at the seat as a case study we find: wide seats are comfortable immediately but after sitting on it for an extended period of time:

You will experience chaffing
You will possibly need to rock your hips to reach around the seat to push the pedals
You cannot use your entire body properly which may lead to injured muscles
You cannot soak up bumps at all which may lead to a sore/stiff back

Conclusion

If you goal is to cover distance get a new bike.  You will go double your distance.
If your goal is to get a good workout and you are not experiencing discomfort keep your current bike and go further.


Can I mix and match cogs from 2 different SRAM cassettes and still expect it to work? My road bike currently has a 12-25 cassette on it.  I really want the cog with 11 teeth instead of the cog with 12 teeth, but I don't want to upgrade to a full 11-32.  If I were to install a new 12-25 cassette on by bike, but replaced the 12 tooth cog with a 11 tooth cog (effectively creating a franken-cassette) would it still work?  Or are the cogs in a cassette not made to be mixed and matched like this?

It's assumed that both of these cassettes would be general SRAM cassettes, but I'm not talking about cassettes like the XG-1190 that have "compatibility notices".

And as a follow up question, would I need to re-calibrate the shifting mechanism after having created this "franken-cassette"?   The number of cogs would effectively remain the same, so I'm hoping not.

absolutely, I do it all the time. just make sure they are sequential. (ie. 11t 13t, 14t etc)


Torque for front caliper bolt. What's the recommended torque of the front caliper bolt for a carbon fork?  The Fork is from a Felt F1. I don't want to damage the fork from over thightening.

This is normally specified by the brake manufacturer, not the fork manufacturer. A summarizing table of common torque values provided by Park Tool is here.

For Shimano, they recommend 70-85 inch-pounds, 90 inch pounds for Campagnolo and 68-72 inch pounds for Cane Creek.

However, it wouldn't hurt to check with the fork manufacturer and the brake manufacturer's documentation.


What width between dropouts is suitable for a hub of Xmm? For a hub of 120mm, what would the dropout spacing be on a typical frame?

Or for 130mm, or other sizes - in each case, how close to the hub width should one expect the frame spacing to be?

You can find the whole gamut of tolerances, especially if you include very low-end bikes. All the numbers I have are my own estimations but they are based on taking rulers to plenty of frames and taking wheels in and out of thousands more.

There is no formal rule for what's acceptable, so any answer is likely to be viewed as too tight by some and too loose by others. However, a lot of framebuilders and industry types see +/-0.1mm as the gold standard for most of the key frame alignment tolerances on higher end bikes, including dropout spacing, rear end alignment as measured with a Park FAG or similar tool, and a bunch of other dimensions. Many decide upon .1mm as the number where if you try to do better you'll be chasing ghosts, struggling to reproduce measurements, etc. A lot of nicer bikes measured out of the box will conform to that for their dropout spacing.

Less premium but still "dealer-level" bikes these days are almost always +/-0.5mm or better for dropout spacing, although occasionally you see a bike where it's more like 1mm.

Low-end and historic bikes are way more all over the place with dropout spacing fidelity. On a contemporary steel department store bike, it wouldn't be surprising to see +/-3mm. For aluminum the dropouts can't be leaned on to flex into conformity the same way and things aren't quite as bad, maybe half that number.

You mention 120. Bike boom bikes had very sloppy tolerances for dropout spacing, probably something like +/-3mm. Good modern track and singlespeed frames are usually very close to dead-on, like +/-.2mm or better. Quickly dialing in optimal chain tension is a total nuisance when you've got gap at the dropouts.


Squeaky coasting and back pedal I recently bought a bike overseas rather than at LBS (no LBS had the type of bike I wanted).  Now the bike makes a strange noise and I can't bring it in for servicing (buy from LBS when you can!).  Could anyone give me any pointers to what could be the cause of this?

When the chain is on the largest (size 34) or second largest cog and I am either free wheeling or back pedaling, there is a squeaky sound.  When the chain is on any other cog there is no so such sound.  Visually, there is no contact of any part where contact should not be.

Below is a link to a video.  What could this be?

Thanks,
Mark

 video recording of the behavior and sound

It was the freehub; when it is pulled away from the wheel while turning it makes the sound.  I guess putting the chain on the largest cog makes it pull the freehub slightly out.

I have not solved it yet: this freehub apparently needs a 11 or 12 mm hex key to be removed rather than 10 mm and 10 mm is the biggest I currently own.


Is it worth buying carbon fiber road bike for short commutes? I'm planning to use a bike for rather short commutes (max half an hour), will the carbon fiber be noticeably more comfortable than aluminium one?

Comfort isn't really an issue for a 30-minute ride, as long as the bike fits. Also, for any given price point, an aluminium bike will have better components than a carbon bike, so will probably be more enjoyable to ride.

For a commuter bike, I'd be much more worried about theft and damage, unless you have somewhere secure to park the bike at work.  If you are worried that aluminium will be too harsh, you're probably wrong but I'd consider steel instead, rather than carbon. Or just put wider tyres on it. I've ridden rigid aluminium hybrids with 28mm tyres and had no comfort issues at all.

Any good bike shop should be happy to let you take a test ride of at least half an hour on any bike you're thinking of buying.


Best solution for 2x8 index shifting I've been riding a pretty well-tuned frankenbike (I call it the argos, I've had it for 15 years) set up with claris 2x8 shifters (r2400) and dura ace (7700) derailleur on the back with an old ultegra fd.  I was using bar end shifters, but I changed to a flat bar.  I ride hard in the NYC streets for 100+ miles a week. Unfortunately, my claris shifters are terrible, slow to shift, and have a crappy feel, and I want to get something that actually shifts crisply and cleanly.  I want to keep riding 8 speed because I like it and it's durable, I have a compact cassette (13-23 w 38/52 up front, the 52 is ramped/pinned, great for city riding) that I really like riding, and my bike is set up right, but the shifters are really not giving me the performance I want.  The front shifter especially is terrible.
I know that I'm probably not going to find a top quality 2x8 set, but maybe there's a 2x9 set that I can use with a jtek shiftmate 2 to run my 2x8 bike.  Here's what I'm considering:
9 speed road:
SL-R660 (which are pretty rare, and will cost a lot) with jtek shiftmate2 (+$50) ("ultegra/xt level")
8 speed mountain:
XT SL-m739 XT which will cost a lot for the rear, and I'll stick with the claris r2000 front
XT SL-m740? I think it's probably the same mechanism
XT SL-m008 (are these the same as the above?)
XTR sl-m951 which will cost ????, and I'll stick with the claris r2000 front
SRAM attack 8???
Microshift r8? (looks cheap)
9 speed mountain:
XTR SL-M970 with jtek shiftmate2 (+$50) and claris front
XT 750/760/770 with jtek shiftmate2 (+$50) and claris front
Saint 800/801/810 with jtek shiftmate2 (+$50) and claris front
I basically just want the best performing 8 speed shifter[s] and I'm willing to invest a bit (less than $200) in order to get something that is going to last (i.e.: has alloy internals, has bearings).  I'm wary of looking into current or more recent 8/9 speed flat bar shifters after my experience with claris.
I'd love to hear from people who have experience with these.

Better 8 speed shifters than exist now are pretty unlikely to start existing in the future, so any recommendation is unlikely to become obsolete.
For robustness, the hot setup is SL-BS64 shifters (the ones you already have if they're Shimano) on Paul Thumbie mounts. Loctite the heck out of the mounting screw for the shifter part. They perform great too, provided you enjoy using thumbshifters.
If you really want trigger shifters, another avenue that would produce good results is any higher end flatbar road set like the one you mention, or any left friction thumbshifter plus the best 8-speed Shimano right shifter you can find in good condition. XT, LX, and Deore have all existed, and most will be better than your Claris. (I will say that the tactile feel of the Claris set you have is of course mediocre, but they work fine, so any serious performance problems you're having with it make me suspect other problems, i.e. cable/housing friction or a slopped out RD.)
Any pre-11-speed Shimano flatbar road left shifter should work in conjunction with any 8-speed double Shimano road front derailleur. There are other things that could be causing your bad front shifting, ie weird chainring spacing or bad FD positioning. What won't work well is putting a mountain shifter on a Shimano road FD. They pull more cable. One can usually make it work by starting with a bunch of cable slack, but it's not pretty.


Chain skipping and loud noise when pedalling Last year I changed old chain, all cables, rear and front derailleurs with new cheapest shimano parts. It has 7 speed cassette with tourney 6/7 speed rear derailleur. As summer started I took this bike for a ride and then immediatelly noticed this strange thing. When I pedal harder there is a loud noise which looks like is coming from rear wheel (feels like chain would slip) end and then it seems like the chain would slip and my feet goes all way in and there is just loss of force. Basically the bike is unusable whenever you try to pedal any harder. I tried to see if there is actual slippage of chain but it doesn't look like that is happening. Then I tried to inspect if  freehub is somehow skipping as I read somewhere that this could be the problem, but it engages correctly and doesn't slip. The cassette is quite old but it's teeth still look ok. I tried to change chain, all cables and even tried different casette. But the problem persists. I tried to readjust both derailleurs. When I try test this without actually sitting on bike and pedalling this never happens. Gears are shifting smoothly. However, when I sit on the bike and try to pedal. Immediatelly this chain slipping sound happens and pedalling becomes useless.

If the skipping started happening right after you replaced the chain, I would suspect that the cassette needs to be replaced.  If the chain has excessive wear, it causes a wear pattern on the cassette that will prevent the new chain from engaging properly under heavy pedaling load.  It is hard to discern this wear pattern by visual inspection.

This situation can be avoided by replacing the chain before it's worn excessively. When the chain wears, the wear is on the pins, so the chain gets longer. The chain should be replaced before the increase in length is 1%.

Wear can be checked by measuring the length over a number of links using an accurate scale.  The pitch (distance between the centers of pins) is 1/2 inch, so a new chain should measure 12 inches over 24 links. The chain should be replaced before this measurement reaches 12 + 1/8 inches.

Alternatively, there are special chain wear measurement tools made for this purpose.


Is the Park Tool Allen Wrench going to strip out bolts? I am fed up with cheap allen keys.  I've bought a few from local hardware stores, but a 5mm is usually way off, and I end up rounding off the key, or the bolt.  I've thought about buying this parks allen key:

http://www.amazon.com/Park-Tool-Allen-Wrench-4-5mm/dp/B005R638TC/ref=sr_1_2?ie=UTF8&qid=1423706361&sr=8-2&keywords=parks+allen+key

It has 5 star review from 5 customers at the moment, but I'm still wary.  Anyone have any experience with it?  Or is it just junk that they slapped a parks tool sticker on?

Also, if anyone has any advice on allen keys from their experience I'd love to hear.  Is it worth paying for Snap-on keys, or something similar?

I'd love to hear others have this problem too, and it's not just me that can't loosen or tighten a brake lever without rounding something off.

I have never had a problem with Allen keys rounding. Using the correct size, using them correctly (Inserting them fully and not letting them slip out the bolt) and not using too much torque for the bolt size means even cheap Allen keys will last a lifetime.

If the bolt head has rusted or has gunk in it, you sometimes cannot easily get the Allen key in all the way. In this case cleaning the hole is required. Abusing the bolt/allen key by only inserting it part way is the most likely cause of problems. Workshop quality tools will survive abuse such as this (although it's more likely the bolt won't).

If you are having problems rounding the Allen keys, workshop quality tools to likely just move this problem to the bolt, making it a much bigger problem.


What are some oft-cited benefits of electric assist on a mountain bike? Recently, electric mountain bikes have been hyped quite a lot, and I have seen a lot of them for sale at LBSs and have even seen a few "in action" despite that I never go mountain biking (i.e. I see them in the city). While the benefits of electric assist are easy to point out for city-/commuter-style bikes, the reasons I can imagine for electric mountain bikes seem a bit more dubious. Regardless of their truth/objectivity, what are the most common reasons for using electric assist on a mountain bike?

As stated above, using electric assist in commuter bikes is (to me, at least) less "controversial"  because sport isn't the top priority for this style of riding. However, mountain biking is inherently a sport... so I'm having a hard time imagining the "obvious" benefits... so what are they?

I don't know about "oft-cited", because I haven't actually seen any cited. But distinguishing these standard electric assist bicycle from the  "electric trail bikes" that have been round for a while, I can guess some of the advantages compared to an unpowered MTB:

For the Rider/Purchaser (not necessarily the same person)

ability to ride places they couldn't otherwise get to
more ride options with a fitter partner ("together time" in many couples)
unique bike. For a while at least, no-one else is like to have one of these.
easier riding. You can stay unfit, but still go mountain biking
for off road touring, ability to carry/tow more gear

For the manufacturer

more profitable, because it's a small market niche
less competition
opportunity to "lock in" retailers by requiring brand-specific parts and test equipment
easier vertical integration via the same mechanism (more of the parts are from one manufacturer.

I suspect the market for basic, obvious MTeB's is more couples and families, allowing them to go out for a ride together that's more interesting than just easy laps around a well-formed trail in a park.

Of course, none of this is actually new. The first power assist mountain bike I saw had a bunch of lead-acid batteries bolted to an early mountain bike, and that would have been before 1990. I've been seeing what look like reasonably capable MTeB's in catalogues and online for quite a few years.

The slow change I'm seeing is that there are more "MTB parks" and so on with very easy trails, so it's more realistic for someone who rides with assist on the road to also ride the easier trails. The technology is also there now to conceal the motor to a large extend, reducing the reluctance of unfit people to buy one and go out riding with their fitter mates. At some point that tech crosses over with outright cheating in races, which we're also seeing more of now.

What we have been seeing for a while is "electric trail bikes" sold as  "electric mountain bike", with the huge benefit over a petrol "trail bike" is that the former doesn't need registration and can often be ridden in areas where motor vehicles are banned. This is also why they're controversial with many MTB people, as they allow silent, very fast, and unexpectedly heavy bikes to use MTB tracks.

There are two differences between those and power assisted bicycles though. Bicycles in most countries are limited to 200W or 250W, where trail bikes are usually 1kW or more. The second is the key "assist" word. The bicycle can be ridden without power assistance, the motorbike can't be. That makes the difference between an "electric mountain bike" and a power assisted bicycle pretty simple - if it's under 250W and you can ride without the motor, it's a bicycle.

There was a case in NSW where a cop told someone on a "pedal scooter" (looks like a motor scooter, has pedals sticking out the sides) to turn the motor off and pedal it a few hundred metres, which the rider was unable to do. Ticket issued, court case lost.


How can I remove a stuck rear cassette? I've been trying in vain to remove a rear cassette that I myself installed about a year ago.  I may have over-tightened the lock ring and now I can't remove it no matter what position I hold the wheel-chain whip-wrench combination.  Any advice on what to do to get this cassette off (short of going to my LBS)?  The wheel is relatively new and the cassette is very new, and the reason I want to remove the cassette is to replace a broken spoke.

Have you tried holding your tool like this:

I have just discovered it (instead of the classical "one tool per hand" technique) and it helped a lot.


700 x 32c Tire on 27 x 1 1/4 Wheels? I have some vintage 27 inch wheels and I was wondering if I could use some 700 x 32c Tires on them.

Thanks

Really doubt it.  27 is 630 iso and 700 is 622 iso.
SheldonBrownTireSizing


What are these holes for in my Diamondback Sorrento? The holes are threaded and 20mm apart. There are identical holes on the other side where the gears are. Can I install disc brake calipers through these holes?

They are rack and fender mounts and you cannot install disc brakes with them.

I.S. mounts are 51 mm apart, and post mounts are 74 mm apart (and look totally different). For more details on these mounts, see this answer.


How to destroy a LOOK pedal as it won't come off anyway I've tried everything, from brute force, WD40 overnight, heat from a gas torch (trying not to damage the carbon crank itself), to using an extended arm for extra force.

Nothing will remove this darn pedal! The 8mm hex hole is now slipping so there is no more grip. Even the alloy wrench started to bend!

Ok, here is the low down.

Colnago C40 frame with Campagnolo Record Ultra Torque carbon cranks. Left pedal comes off easy, but the right drive pedal is fooked! Both pedals are LOOK Classics. Both were put on 2 years ago with grease, so they should have been easy to unwind. I suspect I annoyed someone on the bunch races and he went over and over tightened the pedal in vengeance! Bastard! I have an idea who it was too!

Anyway, the question is - how do I kill it!?

I am thinking nice clean fine metal blade on a hack-saw, cut pedal off, then drill middle outwards and hopefully it will unscrew itself without unscrewing the thread attached to the crank!

Any other suggestions?

Thanks

Heating the pedal is not going to help here.  Cool the pedal might.  But if the hex is stripped too late.

Use penetrating oil like Liquid Wrench over WD40 for this.
I would have soaked it two days in penetrating oil before I went brute force.
The risk of brute force is you that you strip out the crank.

Use a drill press as it is really hard to center by hand.
If you get the bit big enough it will fracture the pedal axle.
But you don't want the bit big enough to scar the crank.

I would see if you can get the pedal part of the pedal off and have enough of the axle to grab on to with a pipe wrench.  Soak it for 2 days in penetrating oil before you go at it with a pipe wrench.


How to clean rubber and plastic parts with sticky, thick teflon-based lube stains? I once lubed inside a Grip Shifter with Finish Line teflon lube, and used that for a long time.

Now I disassembled everything, and the outer rubber part is quite stained and sticky.

I tried to brush the teflon aside with water and soap, and even a mild degreaser, but since teflon is not exactely grease, I just spread the stains even more.

So, question is: Which substance / method should I use to clean that?

Try Dawn Dish soap its a little bit of scrubbing but it seems to work the best, its chem resistant so everything I have tried only makes it more sticky but dish soap hot water and work gets rid of it the best.  Good Luck


Will a dehumidifier dry out the lubricants on my bike? I keep my bike in a utility room at home which doubles a larder, extra storage, a shed, a laundry room etc. etc... It's one of those rooms. But as a laundry room I have a dehumidifier which is running most of the time as there are a lot of people living in my house so there is often clothes drying.

I was wondering if the dehumidifier would dry out the oil on my chain? I try to clean, degrease and relube my chain regularly so I'm not particularly worried about this happening, more curious. But this then got me thinking, would it be of more risk to the areas that don't get treated as often, so lube around cables or deeper into the mechanics around bearings etc.?

Probably one of the stranger questions I've asked about a bike :)

No.  Here's a vague, handwavy descrption of why: A dehumidifier will reduce how much vapour (oil or water, so long as the boiling point and saturation vapour pressure at room temperatureare appropriate) is in the air.  In the case of water, which is in plentiful supply, there's usually enough vapour in the air to affect the rate of evaporation, because there are plenty of sources, both natural and man-made.  In the case of oils, the amount present in the air is so low that reducing it further will have no effect on the amount that can evaporate.

Where the dehumidifier might have an effect is that it blows out slightly warm air (assuing it's working fairly hard).  The extra heat might just be enough to increase the rate of evaporation, but in practice I'd be surprised if the temperature of a bit of bike in the output flow of a dehumidifer could get 5°C above ambient -- much less than leaving it in the sun.


Removing stuck front brake caliper from a modern road bike I'm trying to remove the front brake caliper from my Specialized Allez.  It took me a long time, a lot of effort, and plenty of 3-in-1 to finally loosen and remove the recessed nut that screws onto the caliper bolt.  I expected that the caliper would then come off the forks with ease but unfortunately this didn't happen.  Am I missing something here or should the caliper be able to be removed when the nut is undone and removed from the bolt?  As I mentioned, the recessed nut was really difficult to remove and there was a bit of rust around it.  Maybe the bolt has rusted to the forks too.  If so, any tips for removing the bolt and caliper?

This is an old post but it came up in Google. I had the same problem. It's worth trying a bit of heat. I used a hairdryer to gently heat the area and this helped the bolt come loose.


What is it called when you ride around on your back wheel? What's it called when you pull a wheelie and hold it while you ride around on just the back wheel?  I learned the term as a kid and I think it started with "c", but I could be wrong or the term could be wrong.  It's been bugging me ever since I found this site and went through the glossary and Wikipedia's.

Edit: I'm specifically looking for something to distinguish riding on the back wheel from  stopping on it (a manual).  Both involve pulling up the front wheel (a wheelie). shufler's answer captures this distinction, so I'm just looking for other words for it at this point.

Balancing on your back wheel (with the front wheel in the air) while pedaling is called a catwalk.

(Sorry about the wikihow link, it was the only source I found other than youtube)

Edit: It seems the wikihow link is dead. As far as I can tell a manual is leaning back and raising the tire but not pedaling. I found a couple of other links that make reference to it being called a catwalk:

Basic Bike tricks and Skills, user Wesley666 comments:

  Not a Wheelie.  Its a Cat Walk.  A Wheelie you stay seated and ride on your back tire.  If I am correct you actually stand up and pedal up and keep pedaling, which is a Cat Walk.

Learning how to catwalk wheelie -- this video is specific to a dirt bike.

It's very possible that catwalk is a regional term.


Front Fork Won't Stay Centered I got hit by a car and it damaged the front wheel and fork. I took my bike (canyon inflite AL) into a store and they ordered a replacement fork and wheel. The problem is they had to replace one of the internal bolts in the headset because it had been stripped in the crash. I keep trying to reset the handlebars to be centered and they feel centered for a bit then it seems like they are off again. Has anyone else had this problem or have a solution they'd propose?

Presumably what is happening is that the stem bolts are not providing enough clamping force of the stem onto the steerer, and the stem is moving off center. You can check the alignment of the stem and wheel by looking down on then from above. The stem being mis-aligned should be obvious.
There are no 'internal bolts' in the headset, so you may mean either the steerer tube expansion plug or one of the stem bolts. If one of the stem bolts was stripped the thread in the stem may also be damaged.
Try making sure the bolts are tightened to correct torque (should be printed on the stem). If a bolt will not tighten to that torque the stem thread is damaged and you need to replace the stem. You can also try a carbon installation compound that helps grip carbon components.


Can you record multiple rides on a Garmin 500 and download more than one on Strava? Can you record multiple rides on a Garmin 500 and then download them sequentially onto Strava?

Valerie Jones

Can you record multiple rides on Garmin 500

Yes you can record as many rides as there is room on the internal memory. Once you have completed a ride hit stop, then hold the lap/reset button for 3 seconds to get the unit to save the ride and reset the screen.  This will save the ride as a .fit file on the unit (Figure 1).

The Garmin 500 is an older unit with less memory, but right now I have 124 rides on my Garmin 500 dating back to Nov 2018 and there is still plenty of room left.

  then download them sequencially onto strava

You will need to connect the Garmin unit to a compatible computer using the supplied USB cable, it will typically mount as an external drive (Figure 1). From there you can manually upload the .fit files to Strava using their file upload feature.

Alternatively you can install Garmin Express on your computer, which will automatically upload the .fit files to Garmin Connect when you connect the your Garmin 500 to your computer.  Strava can then be set up to connect and download activities from Garmin Connect.

Personally, I just do it old school (file upload).

Figure 1. Location of Garmin 500 activity files.


Should I lubricate a BBS01 clutch? I am completing the rebuild of a BBS01 electric bike mid-drive motor from Bafung.  Would like to lubricate and protect every part properly before reassembly. Should I lubricate the clutch and if so with what lubricant?  I have read concerns about slippage in a lubricated clutch.  Thanks in advance!

Not sure I'd call that a clutch.... ;) More a freewheel.

I have done jobs like this in the past, and I found using a Lithium Grease (very thin, textured a bit like facial cream) works great, so long as you only line it on the teeth.

On the one I had, however, it had a seal which meant there was no way the grease could get out. Something important to note is that, if you DO have one of these with a seal on them, don't competely fill it with grease. Where you have moving parts, you want a void and a way for it to 'breathe', otherwise the seal will physically pop. You want more air than grease; Air is compressible, grease (classed as a liquid) is not.

If it's not sealed, only a very thin layer. It's purpose is to keep it lubricated and to keep the teeth themselves clean and not directly contacting metal-on-metal, a bad thing in an electric motor which moves very fast under heavy load. If you use too little, the gears will chew each other up, making what little grease there is turn into a grinding paste. Too much grease, and it'll start blurting out of the side, onto other vital, expensive components.

Good luck!


Do I have Direct Mount or Hanger Mount? I'm very very new to bicycles and obtained a little project for me to work on, hence the amount of rust on the parts currently but I'm not sure if I have a direct or hanger mount derailleur? I'm 100% I need Shimano I just can't figure out which Mount haha.

I have attached a picture to the post (don't mind the disgraceful amount of rust and whatnot). Any help is appreciated!

That is a Direct Mount derailleur.  The hanger there is a separate part that is part of the frame.  When companies call them Hanger Mount or hanger style, the hanger is built into the derailleur and not removable.  To replace it, order the Direct Mount one.


Can anyone identify this badge? I’m in the process of restoring my Dad’s bike so that I can start riding again. All the badges are intact but I can’t find any information about the bike. He’s had it for as long as I can remember (my whole life) so I’m assuming it was made in Japan in the 1970’s. Can anyone identify this badge?

Edit: I don’t believe it’s a Hero.  The sticker on the up tube says “Made in Japan.” I’ve searched a few Japanese manufactures that I found on Wikipedia but couldn’t find a Hawk reference on the few hyperlinks I could access.

Here is an image of the bike.

Please keep in mind that the handle bars, seat and front fork in this image are not the originals. It’s a standard 10 speed road bike.

The Australian police have some Hawk bikes, and there is an Australian company "Hawk Racing" I mention this as there appears to be two Boomerangs on the badge. Should that read "Hawk CCM"  "Hawk ? Cycle Manufacture"
Of course this could be a resellers badge and manufactured elsewhere.

ref police

ref company


Are all ready-made wheels sold "cassette compatible" only? I will have to change my wheels on my old trusty late-80s Peugeot (PS28) soon. The rear wheel is mounted with a freewheel-type 6-speed hub (not cassette).

I was wondering if all ready-made wheels that you can buy are only cassette compatible (therefore 7-8-9 speeds)?

My derailleur is Shimano 105 with mixed friction/indexed mode, mounted on the tube, I suppose it is only designed to support an indexed 6 speed.

A LBS told me I could only change the rim of the wheel given the hub is in good condition.

What would you suggest would be the best way to approach this?

If your hub is in good condition & you wish to keep it having the wheel rebuilt is the way to go. However if your shop is trying to charge you more then 100$ish dollars for a rebuild, especially on an older hub perhaps consider doing the rebuild yourself. Re/building wheels is not a particularly difficult task with a wheel stand & proper tools all of which are readily available online for reasonable prices. However it can be exceedingly time consuming so consider this aspect as well the reality is that it most likely would take you shop just as long to rebuild the wheel but some times it's more easy to just pay someone.


What is the best bike for me? I'm a man 5'8" planning to get a new bike as a beginner. looking for going around the city + fitness. My budget under $800. The bike that I need it should make me fall in love with Road bikes.

The best bike for you is one that you want to ride.
Your bike needs to be comfortable TO YOU which means the correct size.
It needs to suit your needs, whether that be commuting, training, shopping, adventure, offroad.
It needs to be affordable without breaking your budget, and leave enough spare cash for those extras like helmet, a bag, tools, spares, gloves, or whatever else you need.

The reason that a used bike is often suggested is because they are generally a lot cheaper than a new bike, plus in these C19 days the supply chain can be lumpy.
A used bike can let you ride the bike you think you want, and then you can buy another used bike of a style that grows on you later.  It is not uncommon for riders to want a squishy MTB to ride to work/school, and then realise how slow they are compared to something more road-oriented   (for example)
On the other hand, a new bike comes with some sort of warranty depending on your location.   Some people cannot stand the idea of riding a bike that someone else has ridden, so new is their only option.   That's okay too, but it costs more.
A bike that is bought with the best intentions but only gets a few rides before being stored, that's a ROPA (ridden once, put away) or a "Garage Princess"   If you have one of those in your extended family, then see if you can borrow it for a try.


What is the total equipment weight of a tour rider? What is the total weight a Tdf rider carries up the hill apart from his own bodyweight? The bike is around 7kg, maybe a bottle with some water.. What about helmet, clothes, shoes etc?

Weighing some of my own gear, and allowing some reduction because I'm not especially up to date ...

Helmet 350g to 400g
Shoes 300g to 350g
Outfit 350g to 400g, 100 to 200g more on a cold or wet day.
Misc 150g (sunnies, comms gear, etc)

Total... 1.15kg to 1.3kg, plus .1 or .2kg depending on conditions.


How to break reinforced Shimano pin? Sorry if my technical English is a bit imprecise.

I just put on new Shimano CN-HG53 chain. I joined the ends not with regular pin, but with provided reinforced one (like one of those below).

The problem is the tip (end) of that pin is entirely outside the link now, and I should break it off. But it is so well made, that I cannot do this. With bare hands -- not possible at all. With pliers

I move the pin tip up-down, but entire chain is rotating (even if I grab it with my hand). I could hold still chain with another pliers but I am afraid of damaging the link I would hold with pliers.

So what tool is required to break it off, and how to do it?

Ok, I did it! :-D I took two plates of steel, drilled a little hole in one of them (for the pin), then put the chain between them (pin goes through the hole of course). This served as vice, but because it was not mechanically clamped I could control the force.

Then I used pair of pliers, and without a sweat, pin snapped.

I used the same chain before, but I used regular pin, after a year it came out of the chain (partially), thus this time I used reinforced one. We'll see how good it is...


How do I taper for a century+ ride? I am doing a 210km (130 mile) ride on Sunday. I assume it'd help me to taper but I'm not sure about the most effective method.

How much should I ride in the last 3-4 days before the ride? My current plan is:

Wednesday: Normal 40km (24 mile) commute
Thursday: Lunchtime ride of
20km (12 miles)
Friday: Lunchtime ride of 20km (12 miles)
Saturday: Rest
Sunday: Ride

This page (which is actually related to the ride I'm doing) suggests that I'm close, but should rest on Friday and do a short ride on Saturday.

Some information about my training:

I've done this ride before and I'm confident I can finish it, I just want to finish it as strongly/comfortably as possible.
I've done 100km+ (60miles+) for the last 3 weekends in training, along with daily commutes

Update

I ended up doing a slightly longer ride on Thursday, but other than that I stuck to the schedule above. I did feel more rested at the start of the Sunday and I was grateful for the day off on Saturday.

I also Carbo loaded.

Given the variables I'm not sure what helped, but I did feel strong for the ride and didn't 'bonk', which was a definite improvement over previous years.

I would agree that a short ride on Saturday is useful to keep things ticking over, resting on the Friday, so long as the substitute commute isn't too stressful, might be more useful. Your body needs some down time and a 'clean' 24+ hours is quite important for genuine recovery.

The thing to do on the Saturday is to use the short ride as a dress rehearsal, use all the kit that you plan to take with you - you've probably got more time to do this on the Saturday.

So, if you're going to drive to the start line, then do that on the Saturday too. At least, pack the bike and bits into/on to the car and drive somewhere to do the test ride. Do your best to mimic game day. Just to let you relax knowing you haven't forgotten anything. This is especially important if there's anything new in your setup - nothing new on the day is a crucial mantra (not new shoes, socks, tyre, nothing!).


What does "Electronic Ready" mean on a Giant Frame? I just purchased a 2014 Giant TCX SLR 2, and noticed in the spec sheet that the frame is "Electronic Ready"

What does this mean?

http://www.giant-bicycles.com/en-ca/bikes/model/tcx.slr.2/17669/73500/#specifications

I was hoping this would mean ready for a speed/cadence sensor but that seems to be "RideSense ready" in terms of Giant lingo.

Based on comparison with the Giant Defy Advanced line, it seems to mean that you can run an electronic drivetrain (such as Shimano Di2 parts) - you have to mount things like a battery in order for the shifters to work and what not, so the frame will need to have the wiring harnesses and battery pack mounted.

This link shows the TCR line in 2012 with this done.

What does an electronic drive train mean for most people? Likely, just an emptier wallet. But thats a different question all together.


What is the optimal cadence? I have heard that one ought to turn the pedals at 90rpm. However, I do so much slower, especially while standing, and would like to understand the argument behind this number (or any other number). So:

What is the optimal cadence of a cyclist. Why? Does it depend on the terrain? Does it depend if the rider is sitting or standing upright? What are some possible consequences of deviating too much from the proposed number?

Possible duplicate of "What Cadence Should I Aim For", but I didn't find there the "whys" except for "it will grind your knees." However, I find riding upright with slow cadance no more demanding than walking up a hill with a backpack.

"Optimal" cadence varies with what you're trying to optimze, so your question doesn't have a simple answer.

Freely-chosen Cadence vs. a Targeted Cadence

A recent review by Hansen et al. summarizes what is currently known about factors affecting choice of cadence. In particular, they conclude "[d]uring high-intensity cycling, close to the maximal aerobic power output, cyclists choose an energetically economical cadence that is also favorable for performance. In contrast, the choice of a relatively high cadence during cycling at low-to-moderate intensity is uneconomical and could compromise performance during prolonged cycling." The first sentence means that experienced cyclists freely choose the cadence that produces good performances and they don't need to have someone dictate what that cadence is. The last sentence means that having an inappropriate cadence forced on you can be detrimental to performance.

Cadence and Power

The relatively recent proliferation of on-bike power meters that record both power and cadence has helped provide additional data that bears on the issue. By definition, a cyclist's power output = cadence * crank torque * a conversion constant (the conversion constant depends on the units you use for measuring power, cadence, and torque; if you measure power in watts, cadence in radians per second, and crank torque in Newton meters, the conversion constant is 1). If you are racing at high power, or riding leisurely at low power along a bike path with your children, or on a spirited ride with friends, you will certainly choose different power levels; what has become clear from the data is that riders, even very experienced ones, choose different combinations of cadence and crank torque to match higher or lower levels of power. They do not always choose a fixed cadence and change gears in order to keep in robotic lockstep with that number.

Cadence and the Type of Ride

But even if we exclude leisurely riding and focus only on racing (at high power), cadence and crank torque vary according to the type of race. Here are cadence-crank torque plots for the same (domestic pro) rider in three different types of races: a road race, a criterium race, and a time trial. Torque is measured in Newton-meters, while cadence is measured in rpm. The thin red dotted lines show the combinations of cadence and torque that produce 300, 500, and 700 watts. As you may be able to see, the three different types of races call for different combinations of cadence and crank torque. The time trial shown here was done at a relatively steady power level but the road race and criterium race were much more variable. For those races, the rider attained higher power by increasing both cadence and crank torque. This is a quite common pattern for road racing, and it helps to explain why observers often remark that racers pedal at high cadence: the racers are also pedaling at high power and high crank torque but the only visible clue is the high cadence. This, then, is the basis for the sentences quoted from Hansen et al. above: the cadence used to produce high power appears to be neither economical nor performance-enhancing at low power. Just because you see a Tour de France rider pedal at X rpm doesn't mean you should pedal at X rpm (unless you also produce Tour de France levels of power). Likewise, just because you see that a Tour de France rider spends little of his time at Y rpm doesn't mean you should avoid pedaling at Y rpm. Your needs, abilities, and goals will differ.

Cadence and Terrain

Your question also asked whether cadence varies with terrain. Here is a plot of cadence and torque for a rider who was doing a set of hill intervals. The upper left panel shows his cadence and torque over the entire ride. The upper right panel shows the elevation profile for his ride; as can be seen, the ride was slightly rolling from his house out to a hill which he climbed and descended four times, then he returned home over the rolling road. That upper right panel marks the climbing portion of his ride in red. The bottom two panels show his cadence and torque for the corresponding black and red portions of the ride. As before, the thin dotted lines (this time, in blue) show "isopower contours." Clearly, he used different combinations of cadence and torque on the climbing sections than on the descending and rolling sections.

To emphasize this point, here is a plot that shows cadence vs. estimated road gradient for ProTour rider Gustav Larsson during Stage 3 of the 2009 Tour of California. As you can see, even if we exclude periods of coasting, his cadence varied from around 20 rpm up to around 120 rpm, and as the road gradient became steeper, his cadence decreased.

Cadence and Crank Torque

Do you wonder about the relationship between cadence and crank torque? Here is a plot showing another rider in a "pure" hill climb. The upper left panel shows the relationship between cadence and power; the upper right shows the relationship between crank torque and power; and the bottom two panels show the relationship between cadence and crank torque, one with and one without isopower contours. The bottom panels make clearer that there is often an inverse relationship between cadence and crank torque, but the upper panels show that in this instance crank torque was a larger determinant of power output than cadence.

Cadence and Knee Strain

Some riders claim that slow cadences (below, say, 60 rpm) can injure knees. However, slow cadence cannot by itself injure knees; as you sit at your desk reading these words, your “cadence” is almost surely close to zero but the force on your knees is also low. Riders who make these claims are conflating low cadence with high force. From the plots provided it should be clear that one of the simplest ways to expose the knees to lower force is simply to ride at lower power. Riding at 60 rpm at low power can be done with low pedal force; riding at 90 rpm at high power must be done with high pedal force. So level of power output (also known as “workload”) is a key to understanding joint strain. In the mid-1980s, M. Ericson published a series of studies examining forces on the hip, knee, ankle, foot, and the leg muscles during cycling including this one. Importantly, he concluded, “[o]f the four parameters studied (workload, pedalling rate, saddle height, pedal foot position) workload was the most important adjustment factor for change of joint load and muscular activity. An increased pedalling rate increased the muscular activity in most of the muscles investigated, generally without changing the joint load. Increased saddle height decreased the maximum flexing knee load moment, but did not significantly change the flexing hip or dorsiflexing ankle load moment. Muscular activity in most of the muscles investigated was not generally changed by different saddle heights.”

Cadence and trainers

Some riders will use their indoor trainers and observe that their "preferred"
cadence (perhaps for a particular level of power or heart rate) is X rpm, and then try to ride at that rpm outdoors. As we have seen above, freely-chosen cadence varies with terrain, power, and the way that resistance scales with speed. Of importance here is that trainers also vary in the way that resistance scales with speed. Below you can see a plot for the same rider on two different types of trainers but using the same gear ratio on both: a trainer with a fluid resistance unit, and on rollers. Each dot shows the cadence and crank torque at one second intervals. As you can see, these two types of trainers have very different resistance curves, with the rollers being much "flatter" with increasing rpm. In order to attain the same power, the rider appears to choose higher cadence (and lower crank torque). In order to attain the same level of power (say, 175 watts) the rider's freely chosen cadence varies with the type of resistance. "Transferring" indoor trainer cadence to an outdoor ride ignores both that outdoor rides vary, but also that trainers vary.

"...but..but the hour record is set at high cadence!"

Yes, most of the UCI hour records over the last 50 years have been set with cadences from about 100 rpm to 107 rpm (with the notable exception of Obree, who set his records at 93 and 95 rpm). However, the hour record is set with a fixed-gear bicycle on a track and, more importantly, all of the records have been set at high power and high crank torque. Below you can see the cadence and crank torque for many of the recent hour records based on data from Bassett et al.; the plot shows that for recent records set at sea level, average power ranged from around 370 to 460 watts and crank torque ranged from 36 to 43 Nm. One wouldn't tell a novice rider to pedal at a constant crank torque of 40 Nm yet many advise novices to ride at close to 100 rpm. Using the cadence of world record setting events achieved on a fixed gear on a velodrome track as a guide for more general riding makes about as much sense as using the crank torque of the same world record setting events achieved on a fixed gear on a velodrome track as a guide for more general riding.

Conclusion

The conclusion from all of this is that cadence varies both with the ride and with the rider. In that sense, asking about "optimal cadence" is, in isolation of the characteristics of the ride and rider, a red herring. Without the proper context, asking about optimal cadence is like asking about optimal power, or optimal crank torque.


Can I ride on 15 spokes instead of 16? On my way to work this morning, one of the spoke on my front-wheel broke. I removed it completely, leaving me with 15 spokes instead of 16.

Can I still ride my bike over a 20km distance. I noticed the question was asked before, but I wasn't sure if it was also applicable to a wheel with a lower amount of spoke.

You shouldn't ride on a wheel with broken spokes more than necessary, especially if its a low spoke count wheel (like a 16 spoke wheel). The load gets unbalanced with respect to the other spokes.

Since this is a front wheel, I wouldn't risk riding it. If something does happen to the wheel (such as failure) its far more serious than if it happened to the rear wheel (you can recover from rear wheel failure; recovering from front wheel failure may require you finding your teeth on the side of the road).


Ultra durable MTB for heavyweight rider (370lbs)? Some might remember me from this post. So basically after finding a fix for my dutch bike I was riding around London I now actually moved back to Germany. To the countryside to be exact and to the hilly countryside as well! With lots of forest. So now I am looking into building or buying a very rigid MTB. I will be mostly riding in the woods.

I have also considered an E-Bike for extra boost up those hills but I am not sure if that makes sense or not. The KTM Mighty XL looks really good as far as ebikes go. It is officially rated up to 170kg (~370lbs) but that is actually for the whole bike + rider and baggage. So it's more like 150kg (~330lbs) for the rider. The price tag is probably fair but at about 4000 USD you could also buy a car for that. I am considering it anyways.

However I also want to consider regular MTBs.

What are some features or things that I should look at that would indicate a bike that can take heavy loads — or that you would recommend or should I  have to go for a custom built?

In the past I was given a quote for a custom built back in London by SBC Cycles. Great guys but I couldn't spare the coins at that time so waited until I found the working solution for my dutchie. The built was based on a Surly Troll frame even though that bike was conceptualised for the city but could probably easily be altered to be an MTB aka different tyres.

In general I was wondering as well - is the MTB market completely international or would I find totally different makes in Germany than in the US?

As you probably know specific product recommendations are off topic here. However, three recommendations:

Overbuilt wheels, heavy duty rim, 44 or 48 spokes.
The biggest tire you can run, especially on the rear.
Consider a full suspension bike. A 90kg rider coming off a big drop is going to generate as much force as you will going over a pothole.

Props for your efforts to keep riding.


Is it better fitness-wise to ride at the maximum gear? I just wanted to know if I will be doing more effort while riding at the maximum gear all the time, rather than changing gears constantly.

My commute is an hour long, but I want it to be tougher on the muscles, I've tried going at the maximum gear all the time but I'm not sure I'm doing more effort by it.

Could someone confirm?

No - Struggling away in the small rear cog/large front chainring combo is bad.

Fitness is an overall term that has many components, so:

If you want power you need to work on intervals, which is as fast as possible at full power for short burst times, then recovery time at a middling state.
If you want to train for endurance, being at the steady state for as long as possible, but working to nudge the steady state up to a consistently higher average.
If you want to get somewhere and not be too stinky, riding at 10-20% less than your steady state is good.  I (try to) do this on the way to work, but its not easy.  I leave the fast run for the scenic route home.

Simply pushing really hard on your gears means you're exerting a lot of force through your knees, and mine ache just thinking about it.  Instead you want to pick a gear that keeps you around 90 RPM is the common thinking, but personally I pedal faster.  Any lower than 60-70 is going to damage/hurt your knees faster and produce no gain in fitness.