Carrying a child and balance bike on my bike I have a child who is 2 1/2 years old (28 months actually) and he is about 98cm tall and weighs about 15-16kg.
He has an Islabikes Rothan balance bike which is 3.5kg (7.7 pounds).
When we go to ride his bike he eventually gets tired and I have to carry both him and the bike back home (I am sure all parents can relate to that).

I was wondering if I could get a child seat and attach/hang the bike behind the seat so that:

We can ride our bikes togeather
When he gets tired I can put him in the seat, hang the bike on the back and return home

Also I am thinking that the child seat should be carrier mounted to hold more weight since most child seats hold up to 22kg (~48.5 pounds) and with 16 + 3.5 = 19.5kg they would probably be maxed out if it was frame mounted.

My daughter still goes in a Hamax siesta at nearly 3. It's seatpost mounted and we swap it between bikes. The seat is rated to 22kg (which from the growth charts should take 99% of children up to age 4 and 75% to 5½. We're anticipating being able to use it when she starts school. You don't need to include the weight of the balance bike as that wouldn't be carried on the toddler seat.

The rack-mounted seats don't have a much higher limit - in fact then the limit is usually the rack itself, which has to carry the weight of the seat and the balance bike for you.  So you may actually find a lower weight limit overall despite a higher child weight limit.

But on both bikes we have a rack underneath.

I haven't tried carrying her balance bike at the same time yet - she's not yet into going very far on it. But putting the balance bike vertically, with the handlebars at the top rear resting on the rack, and strapping the balance bike frame to the rack should work (at least on 700C/29er etc.).

I managed to get some quick pictures (I didn't even have time to arrange everything somewhere less cluttered so sorry about the quality).  I wasn't quite how I envisaged:

Note that the balance bike isn't strapped down at the moment -- it would need to be.  A strap attaching the fork/steerer tube of the balance bike to the rack crossbar, and another attaching the downtube to the diagonal strut of the rack against which it's almost resting should be secure.  You may want some padding e.g. blocks of foam. I like the fact that the strap wouldn't be taking the weight, just holding it steady.  I also didn't have time to test ride it, but heel strike shouldn't be an issue given where my pannier comes to.  The rear wheel was probably 15-20cm off the ground, and a bit further out than a pedal - watch for kerbs.

A few notes about my setup that may affect this:

I've set the seat slightly higher than recommended so I can still use the rack for a pannier.
The rack is quite narrow (Tortec velocity hybrid) to fit under the seat properly (I had to take my Topeak super tourist DX off as it didn't fit.

One note of caution:  This much load this far back affects the handling quite a bit.  I built a rack extension when mine was younger and there were times when the front wheel had very little grip.  I solved it by shifting weight forwards (D lock on the forks, handlebar bag for all the stuff you have to carry with a child etc.


Quad QHD-4 Axis Disc Brakes stuck (can't push open) I have Quad QHD-4 Axis Disc Brakes that were probably never maintained and are stuck. There was a lot of grime and dirt all over, the pads even rusted a bit. It probably locked due to this and I also pressed the lever after removal before I knew. For the life of me I cannot move one piston all the way in. I used a flat headed screwdriver and applied all my body weight to the screwdriver but still it would not move. Brakes are bled and completely taken apart except from the large torx screw. I even tried spraying WD-40 but it had no effect.

Is there anything else I can try? Would I be able to remove the pistons if I removed the large torx bolt? If so what bit is that? I cannot find any info on how to do this. It doesn't seem like the pistons can be removed without undoing the torx bolt and I think it would need to be cleaned well before use due to corrosion, dirt and WD-40.

You pretty much have nothing to lose by disassembling the calipers and attempting to free the pistons. They are useless now, so if you break something it does not matter.

You may try contacting the manufacturer (Hayes?) and asking if they have a service manual.

The silver cap with the Torx socket does seem to be the way into the internals. If you can measure the point-point distance with some accuracy (1/10 mm) you can look up what size it is. The Wikipdia page on Torx drivers lists the sizes. If not, take a caliper to the tool store and try different sizes until you get the  right one.

It's the inboard piston that is stuck so if you can take the outboard one out you should be able to carefully drift the piston back in with a short length of wooden dowel or brass rod (old door hinge pins work well) and a hammer.

I could not find any info on these particular brakes online but you could look for other videos about how bicycle disc brakes work so you know what to expect when you get in there. Park Tool posted one recently. It's informative, if a bit silly at the beginning.


Quick release skewer installation help I was wondering if I could easily install a quick release skewer on my Kent 700c Mens roadtech bike that I got from Walmart. If not what would i need to do in order to do so.

The correct answer is 'no', you cannot "easily install a quick release skewer" on this bike.

The easiest way would be to buy a different front wheel that is already built with a QR skewer and swap the whole wheel out (make sure to check for correct size and hub spacing before you purchase). Alternatively, you could buy just a new hub that uses a QR skewer, but to swap-out your hubs you'd essentially be re-building your wheel (spoke by spoke) which requires a lot of expertise and specialized tools.

As an alternative, you might consider finding some vintage winged-nuts. If you can find some that fit your current axles, they will serve the same/similar function as a quick-release skewer (that is, they'd allow you to quickly remove your front wheel without the use of a tool).


Can someone tell me the handlebar diameter of a Carerra TDF road bike from Halfords Does anyone know or can measure the diameter of the handlebars for the Carerra TDF road bike from Halfords.

It was bought a few years ago and the similar specs on the site aren't helpful.

This would be at the point where you'd fit cross top levers, so not at the stem.

Update. It's not my bike hence why I can't measure it. Otherwise I wouldn't be asking. Hoping someone has it and can measure or already knows.

Update 2. I'd hoped to get lucky and that someone here had this bike. Is anyone good at eyeballing the diameter from a video?

Do you have access to calipers? Similar to these. (Pretty handy device to have around if not).

Otherwise, you could take a small string and wrap it around the bars put a mark at the point of overlap, measure with a ruler, then put that high school math to use (diameter = circumference / pi)


Why is Shimano's 105 groupset called 105? The current road lineup is
Claris / Sora / Tiagra / 105 / Ultegra / Duraace

105 stands out as odd because its a number.  Is there some special meaning ?

Research

105 was released in 1983 as a 6 speed groupset under the name "A105 Golden Arrow"
At the time Ultegra was known as "600" so some consistency in a 3 digit number.   Dura Ace was always called Dura Ace, and Ultegra got its name in 1997
MTB groupsets have always had a name.  There are no numbers for the groupset as a whole, though each year's revision has a model number.

Conjecture from the web

105 is the reverse of 501, which came from Levi's Jeans, popular in the late 80s in Japan and matching the "workhorse reliable" nature of the 105.
105 reads as "SOI" or "501" when rotated 180 degrees.  But SOI is not a Japanese nor English word, like Dura-Ace ( Duralumin alloy + Ace 'best') or Ultegra = ( ultimate" + Integrity)
In the late 80s Shimano introduced SIS shifting and SLR braking.  At this time many groupsets were stopped, like the 200GS, 300GS, 400GS, 500EX, and Exage.  New groupsets with SIS/SLR replaced them over time.

So why has "105" persevered ?

This is a non-answer because I've been looking at Japanese bicycling sites and blogs and no one really knows. The closest answer is found here:

105の名の由来とは？
最後に、各グレード名の由来についての豆知識を紹介します。1971年に誕生したデュラエースの名は、素材のジュラルミン（Duralumin）と耐久性を意味するデュラビリティ（Durability）に、世界一のコンポという願いを込めた「エース」を組み合わせた造語です。1976年に誕生のアルテグラは、Ultimate（究極）+Integrate（統合）を意味するコンポーネントです。1982年に誕生した105については、当時のダブルレバーSL-A105の型番を継承し、現在では105というグレード名になっています。

which google translate translate (with some clean-up) as:

What is the origin of the 105 name?
Finally, I will introduce my knowledge about the origin of each grade name [in the Shimano series]. The name of Dura Ace which was born in 1971 is a combination of Duralumin of the material and Durability meaning durability combined with "Ace" which wish of the world's best component. The birth of Ultegra in 1976 is a component that means Ultimate + Integrate. Concerning 105 which was born in 1982, it inherited the model number of the double lever SL-A 105 at that time and now it has become the grade name of 105.

So it's a non-answer answer. The author of this article, Kenji Hashimoto, is a sports journalist in Japan and so it's about as close as one might get unless you ask Shimano.


I wish to get fit, therefore should I have a heavy bike? A lot of people seem take up cycling to get fit, and they'll talk about how light their bikes are.

However, as I understand it, a heavy bike uses more energy to pedal it. Should someone that wished to get fit find a very heavy bike?

I'm going to assume that your definition of "get fit" is to lose weight and develop aerobic fitness. I'm also going to assume that the person in question is rather unfit to begin with.

All in all, a person can get fit (or not) on either a heavy or light bike; it will really depend on how they go about their fitness program.

To achieve aerobic or cardiovascular fitness one needs to engage in an activity that elevates the heart rate to a target zone and keep it there for periods of time. To lose weight, one must burn more energy (calories) than one consumes. In order to do this the activity needs to be done on a regular basis.

On to the weight of the bike... Say a person can choose either a 15lb road bike, a 25lb mountain bike, or a 35lb commuter bike for their fitness program. It makes absolutely no difference which bike they choose in order to lose weight and develop aerobic fitness. The only thing that matters will be how they use the bike. So to get fit, the choice of bike would depend more on the type of use a person desires rather than the weight of the bike.

There are also drawbacks to choosing a heavier bike for the sake of it being heavier. One is that it would be harder on the knees of an unfit person, and even a fit person, if they have to climb hills. Another is that it's just plain harder to have to lug around. And also, it would be much less enjoyable once the person gets fit.

My second job is working as a fitness trainer. If a client came to me wanting to get fit with cycling, I would not recommend that they get a 'heavy' bike. I would recommend that they get the best bike they can reasonably afford, based on the type of riding that they prefer to do. I would also probably recommend that they start out with steady, regular riding and build up to interval training. The question is about getting a heavy bike for fitness; and I'd say no, don't get a heavy bike for fitness. Get a bike that will be frequently ridden.

As a trainer I've had several clients who turned to cycling for fitness reasons. One of them got an 'urban' bike decked out with fenders, rear rack, panniers, etc and proceeded to lose 30lbs and otherwise improve her fitness with a daily 16 mile RT commute, plus weekend fun rides. Another client went with an expensive, light road bike; he managed to burn off 25lbs, and 6 months later rode his first century. So, the weight of the bike shouldn't be the determining factor. Like others have said, it should be about the fun and enjoyment and finding a style of riding that'll be sustained.


Road chainring rubbing on frame Problem

My chainring is rubbing on the right, rear chainstay when I attempted to install my crankset.

Frame: Trek 520 Disc (54 cm)
Crankset: Shimano 105 FC-R7000 (52/36, 170mm)
Bottom Bracket: Shimano Ultegra BBr60 (68mm English)

I have built up a few bikes now but hadn't yet encountered this issue. I was thinking a touring frame would accommodate road cranks, but I guess I was wrong. Trek doesn't provide really any documentation on this frame besides the geometry measurements given on the link above.

Potential Workarounds

Spacers between BB and frame. Based on other forums and Shimano's "Dealer's Manual," this does not seem safe or even plausible. If I add spacers, the spindle will be too short and the inner cover will not sit snugly as it's designed to.
Buy smaller chainrings. I may upload a picture if needed, because the rubbing is on both the large (52t) and small (36t) chainrings. I wouldn't even know what size to buy or how to measure to ensure it wouldn't rub.
Replace crankset and bottom bracket with long spindle and smaller crankset (Octalink, square taper whatever). I'd prefer not to do this, because for some reason I decided to throw the packaging away and now I can't return it.

Questions

What kind of compatibility between cranks, BB, and frames do I need to be aware of to prevent this?
What might be the most efficient/cheapest workaround?
Is there something fundamental I am missing that should come with a bottom bracket?

I don't think you are missing anything. I think these frames were intended to be used with mountain bike triple chainrings. The fully built up version that Trek offers comes with Alivio/Sora 3x9 with a 48 tooth big ring.

If the 52 an 36 tooth rings are just hitting the stay you may find a 50/34 pair provides enough clearance (A 50t ring is 4% smaller diameter, 34t is 5% smaller). The 105 crank has a BCD of 110mm and 50/34 rings are available for it. This would be the cheapest option I think. You should be able to sell unused 105 52/36 rings and largely offset the cost of the new ones.

If a 50/34 does not look like it would provide enough clearance then there are sub-compact 48/32 cranks available (8 and 10% smaller diameter) and I thikg you should be able to find one that is compatible with the Shimano BB. Again, you can sell the unused crank to offset the cost.

Update to add info on chainring compatibility:

Chainrings with a difference of less then 16 teeth (52/36, 50/35, 49/32 etc) will work well with a Shimano road derailleur. A potential problem with small chainring pairs is lowering the derailleur enough. This can be a problem with braze-on mountings but is generally not a problem with clamp on. The limiting factor for chainring size on a crank is the bolt circle diameter. For compact cranks with a BCD of 110mm the limit is about 34. This is for the smaller ring obviously. You can mount a 48/34 pair but then you might have a problem of the high and low gear ranges being too close together.

With Shimano cranks you have to be aware of the differences between the groupsets: bolt pattern and the shape of the ring where it meets the crank body makes inter-groupset compatibility poor.

I think you easiest route would be to sell the 105 crank and get a sub-compact one. I note there is a Tiagra 48/34 option which will fit in your BB.


Rounded out top cap bolt I've rounded out my top cap bolt by using a bad allen key. I've tried most solutions to removing stripped bolts but none of these have solved this issue. If I use a large adjustable wrench and place it on the top cap and turn will this loosen the bolt enough that I can remove it? Also, I would prefer not to drill as I have a carbon fork and may risk damage if the drill slips in the removal process.

If it's an aluminum steerer with a star nut and conventional top cap and bolt, just use a big drill to go through the bolt head. This will remove the top cap. At that point you have various options. Presumably the bolt stub is corroded in place. You could try grasping it with needle nose vise grips, penetrating oil soak, etc. If it's corroded solid you could just pound it down and put a new star nut in for a quick fix. Otherwise, there are various ways of getting a star nut properly out.
If this is a plug, the line of attack is going to depend on the specific design. Most of them would make it pretty easy to drill out the preload wrench flats you've stripped sufficiently to get a wrench down into the plug expander bolt, letting you just remove the whole thing. If it's glued or the steerer has integral threads, you're going to need to get the threads moving somehow to save the fork.
Presuming we're talking about an aluminum top cap and/or bolt, I wouldn't be too worried about drilling. Go slow, use cutting fluid, and it should go smooth. You should have a pretty big buffer to the walls of the steerer.


Rear derailleur bouncing up and down in easiest gear I crossing at a cross junction, so I literally only had a few seconds
  to cross because the cars beside me would turn right. As I pushed
  towards the curb I heard a loud bang.

  Anyway after that incident the rear derailleur now bouncing up and
  down while I pedal in the lowest gear. Only the easiest gear though.
  Otherwise it's shifting up and down the cassette fine.

  what did I do?

It's a shimano tourney on a this bike
https://www.cyclesurgery.com/p/orbea-carpe-40-2018-Q3414421.html?colour=122

I know at least one of the springs is intact because when I push the derailleur inwards, it springs back immediately after I let go.

with the rear wheel out, I can feel there is tension on the cage wheni pull on it

That sounds like either the A or B tension spring on the derailleur broke.

The A spring rotates the cage to tension the chain. The B spring rotates the entire derailleur around the mounting bolt. If you pop the chain off the chainring on the crank to slacken the chain you should be able to see that the derailleur is moving freely without spring tension.

The solution is to replace the whole derailleur, as I don’t believe they can be disassembled to replace a spring.


Issue with the gears? My cycle seems to have this problem, that whenever I change the gear it starts changing from the second sprocket.

Whenever I start from gear one it starts from the second biggest sprocket, though it goes up to the smallest sprocket (6th one) it doesn’t climb back to the first biggest sprocket ever.

What's the issue with it?

The bike is a new one (~5 months). Since I brought it and I am facing the same issue ever since.

Is it really an issue, or is everything fine?

Thank you.

Either your range adjustment is off, or your cable tension.  Assuming your derailleur is not bent or damaged, this is likely what's wrong.

Your range adjustment screw that limits how far toward the 'big' gears you can shift needs to be loosened a little, probably as little as 1/4 turn counterclockwise.

Check your derailleur: you should have two screws, one labeled 'H' and one labeled 'L'.  Try loosening 'L' about a quarter turn.

Another possible issue is the cable tension could be too low, possibly because the cable has slipped or stretched. Make sure the cable clamp that secures the derailleur cable to the derailleur is snugly tightened. There should be a barrel adjuster where the cable enters the derailleur, or on the shifter body on the handlebars.  You might also try turning that counterclockwise 1/4 -1/2 turn.

Finally, make sure your chain is clean and oiled, as the friction can interfere with proper shifting.

Further reference: https://www.artscyclery.com/learningcenter/shimanorearderailleurs.html


Slippage Under Load [New Bike] I got a new bike a three or four weeks ago and have noticed the issue arise this last week or two.

When I'm going up a hill (or any heavy load), my gears will slip.  I don't think it's moving gears, it just seems to slip a bit.  My pedals will lose tension as I hear it slip, then will regain traction about a half a crank later.

This happens pretty regularly while pedaling in low gear, maybe once or twice a minute.

If the bike is three or four weeks old it is most likely due for an initial readjustment. It takes a few weeks for the cables to stretch a bit and the derailleurs and springs to seat. This is why most shops want you to return the bike after a month or so to retorque the hardware and readjust the shifters usually for free.


Luggage carrier for fatbike I need a bicycle luggage carrier (rack) for my Scott Big Ed fat bike, but it is not easy to find one that fits. And it looks like it is not possible to add front rack since the bike has front suspension.

Can you recommend a baggage carrier solutions for the fat bike?

Old Man Mountain sells a kit (PH-SH-F-THRU-BLUTO) for mounting their Phat Wide Sherpa Rack on the front with a RockShox Bluto fork (which your bike has).

To quote the page:

  Phat Sherpa Front with 15mm Thru Axle (For Rockshox Bluto). Comes with Robert Axle Project replacement thru axle and all other parts needed for installation. Part Numbers included in this compilation: PH-W, FK-5F15, AX-15BL, QRXLR170, EX6, CL1.5

Alternatively, you can look at their selection of rear racks.


Chainring replacement for folding bike I have a 20" bike with a single 42T chainring and a 6-speed sprocket. The top speed is pretty low (I'm used to racing bikes), calculated to be ~24kph @90 RPM.
I've measured the 5-arm distance between mounting bolts and it seems to be 68-69mm. This looks like a 120mm BCD, but not sure on that. I can't seem to find manufacturer data, except Cyclone SP5.

I think I need a 52 or 53T chainring, how should I search for one? What would be the cheapest option, given that the bike is practically new but with low-end components?

EDIT: added images to the original post, for reference

I did exactly this with my cheap $50 folder.   The purpose was to expand the useful gear range, to get more hill-climbing gears and more top-end gears.

Its still not a speed demon, but it can do 40 km/h with a tail wind.  Normal cruising speed is 25-30 km/h depending on wind and load and freshness, so slower than the road bike but faster than it was.

It started as something similar to yours, with a 1x6 setup consisting of a single ~42 tooth chainring and a 14-28 freewheel.  Had to use a grinder to get the freewheel off being cheap chinese junk.

It now looks more like this with a 3x8 setup.  The rear wheel was rebuilt onto a 8 speed freehub and I fitted am 11-32 cassette.  Shifter needed replacing too, but the cable and chain was left as-is.  The front chainring was replaced with a triple that I had laying about, so its 26/36/48 tooth.  I did NOT change the bottom bracket at all other than a quick inspection, clean and grease.  All up this gives a lowest gearing of 15 gear-inches, and a maximum of 80 gear inches.  I did not change the rear derailleur mechanism.

Downsides I've never found a front derailleur mech that fits, so for now its running as a "norailleur" and the front chainring is selected by hand, or using a scrap of cardboard for cleanliness.  I have twice changed down while ascending a slope without stopping, using a screwdriver!

Other comments  Cheap plastic folding pedals are dreadful.  As a racer you're likely to put down more power than a simple rider.  Refer to this question and note in the pics I swapped out for some short normal pedals.

The bike gets very dirty too, even with full mudguards as pictured.  I think its because the chain ends up so close to the ground.  Or because it has full guards, this is the one I ride in the rain.

Because of the available low gearing, I use this as the tractor for my bike trailer, which works quite well.

The folding mech clamps are tuned by two grub screws.  Get these exactly right and use loctite to hold them in place.  Else the two clamps develop play, which is a horrible feeling while riding.

Finally - I tend to accelerate this out of the saddle, pushing the bars to raise the opposite pedal.  Almost BMX styles.  However it flexes something chronic so I periodically inspect up close.  It gets stiffer if I ride with the seatpost way down (like top picture)  vs up at "road bike" height for me.

Outstanding plans:

Buy a much longer seat post or get one fabbed
Clipless double sided pedals
Mount a water bottle cage somewhere that doesn't interfere with folding
Find a front mech derailler and shifter


What are the hazards and risks if I keep using a worn rear tyre? I found similar questions:

What are the risks of fenders/mudguards?
What are the risks of untrued wheels?

But I haven't found a structured analysis on the subject of tyres.
Stack exchange technicalities: It is the rear tyres on two bikes in my family that seem to be a concern, so I kept my question specific to rear tyres. But please feel free to edit the title and question if you feel that provides a better balance of things like keeping the question specific vs effort required to provide a clear answer. I just don't know if it's better to deal with just the rear by itself or both wheels together to make this question useful.
Logic: Ideally I would love a structured answer, perhaps based on this article about hazards vs risks. Naturally there may be other ways to approach this.
The hazards that come to my mind are:

Loss of grip in a bend/obstruction avoidance
Braking performance - this is probably fairly gradual until the tyre punctures?
Puncturing - the resistance can probably be measured, with some graphs based on some standard puncturing object vs tread depth?

How the hazards translate to risks then probably depends on several factors, like the sort of riding you do, what mode of failure is developing on the tyre (cracks vs thinning) etc. You could probably write a books about this, right?
Clearly if I'm already pushing my tyres to their limits in bends/braking etc. then the tyres need to be it tip-top condition. I don't think I ever get anywhere near these limits, but I guess I am conscious about emergency braking in commuting on roads.
Do countries have government rules for bike tyre safety, like the MOT rules for cars in the UK? I'm not asking about the annual testing and certification, I'm on about the minimum standards of roadworthiness.
I really thought that this subject has been dealt with on this site or elsewhere, but I couldn't find anything complete/clear/structured.
It if matters, the reason I'm asking is I am a bit of a pessimist (perhaps a primary characteristic), and therefore both a cheapskate and safety-conscious, which I would argue are both secondary characteristics on one hand, but clearly conflicting on the other. Safety and frugal are valid tags on this site, pessimism isn't:-)

If it’s just the rubber tread which is worn down and thinner: Keep using it. With treadless tires you’ll only suffer from increased susceptibility to punctures. Of course with knobby/treaded tires your grip on soft surfaces will gradually decrease.

If the tire’s structural integrity could be compromised: Don’t use it. It could fail catastrophically at any time. Things like bulges, abrasions of the sidewalls, cuts or large cracks are all bad signs.


Derailleur indexing problem - doesn't change from 8 to 7 but skips form 3 to 1 I just fitted a new 8 speed Shimano cassette (CS-HG41-8) and chain (CN-HG40) to my new turbo trainer (Elite Suito). Answers to my previous question suggest that this should work OK (see Can I put a 8 speed bike on a Elite Suito 11 speed direct drive turbo trainer).
The fitting seemed to go according to plan (fitted 2 spacers=1.85mm in total on the trainer's freehub, then the 8 speed sprocket cassette, then the lock ring, then left and right chainstay adapters as required for 135mm dropout spacing, then installed the bike using the quick release and dropout adapter supplied with the turbo trainer). I then indexed the derailleur by setting the high and low limters then tensioning the shifter cable and adjusting it according to the instructions in this YouTube video:

            .
If I adjust the shifter cable tension using the barrel adjuster to get a nice, clean gear change from the highest (8th) gear/sprocket down to the next one then the gears shift cleanly down through 8, 7, 6, 5, 4 but when I shift to 3 the chain skips straight over to 1st gear without engaging 2nd gear. If I reduce the shifter cable tension a little bit then the gears shift cleanly down through the low gears (3,2,1) but there then doesn't seem to be enough tension to shift down through the highest gears (nothing happens when I click the shifter from 8 to 7 and the chain only shifts down when I select 6th gear). I can't seem to find any setup that works at both ends of the gear range. I don't understand how the shifter cable tension can be correct for the gears at one end of the range but incorrect for the other end of the range. It's almost as if the increments produced by the shifter are not quite compatible with the those required by the cassette but shouldn't a Shimano 8 speed cassette work with any Shimano 8 speed shifter? I also checked the rear derailleur hanger isn't bent - it seems fine as far as I can see and I think it worked OK with the old cassette and chain that were on the bike before I repurposed it to use with the turbo trainer. Any ideas where I'm going wrong are gratefully received as I'm basically following instructions here without any huge insight into what I'm doing!
Thanks in advance.

Good description of the problem, I think you've done everything correctly so far and the issue you describe is normally a misaligned derailleur hanger. It doesn't take a lot of misalignment to cause this issue.

I don't understand how the shifter cable tension can be correct for the gears at one end of the range but incorrect for the other end of the range.

You're right, it normally shouldn't because the 8 speed shifter will pull exactly the right amount of cable for the derailleur - shimano 8 speed will always work with Shimano 8 speed. If the gears behave at one end of the cassette they should behave at the other end. Whenever I work on a bike and have this trouble I think 'derailleur hanger' and proceed to straighten it.
You straighten a derailleur hanger with a specific hanger alignment tool, which references the wheel rim itself. A difference of +5 mm at one side of the rim and -5 mm at the opposite side can give problems with shifting like you describe; for a diameter of 622 mm this is a very small bend of the hanger.
Normally this is a rare enough job to pop into the bike shop for a quick adjustment, not least because you will take even greater care not to bend the hanger in future. During a pandemic you can do your own cost/benefit.
As long as the limit screws are set properly, this problem is mostly a bit annoying rather than dangerous. You might find an indexing setting where it's a bit sluggish to go into an easier gear on a certain sprocket, but an extra half push of the lever encourages it all the way on. That's a valuable skill if you don't already do so, but reliable indexing obviously preferred.
Here's a photo of such a tool in action for your reference (it's not a link (!) though videos exist of course)


Help me identify downtube shifter boss type I think I received this frame with standard Shimano cable stops, but they don't seem to fit. Also, I couldn't found this shape of downtube bosses anywhere.
The problem seems to be with the non-rectangular shape of the "base" part of the bosses. I can't fit the cable stop over the base, there's a huge gap and the stop can rotate around.
EDIT: I've shown the frame to a local framebuilder who's been in the business since early 90's and he said he's never seen this type before.

Those look like standard shimano-style downtube shifter bosses.  You would need some downtube shifter levers ending up something like this:

If you want to use brifters (integrated levers) then you need a pair of bosses to stop the outer, which look something like this:

With these, the outer cable continues up to the levers either in a graceful arc, or to the bars so it can pass under the bartape.


How to weight pedals? I have some odd kind of track pedals on my bike. I believe they are clipless pedals; but for description, on one side they are flat and comfortable to pedal with. On the other side there is a raised hump in the middle that is a bit difficult to hop into the pedals quickly for fear of one's foot sliding off.

They are comfortable enough to ride with once I am off and going (though I have become proficient with nipping the pedal with my toe to get it on the right side). However, I would like to weight the pedals so that they rest with the hump side down naturally.

They are similar to these:

Please bear in mind I have already accepted that buying new pedals are probably a best option generally. However, in the interest of modding:

  No suggestions are too ugly or odd as
  long as they work and bear in mind the
  problem of pedal strike (thanks
  @Teddy); I am looking for a pragmatic
  solution above all - hopefully not
  involving too much duct tape!

The pedals you have are known as mountain bike clipless pedals. They have a platform side where you can use normal sneakers/shoes to ride, and the other side with the "hump" is the clipless side. There are special shoes with cleats on the bottom that attach to the pedals,and they're there to increase your pedaling capacity by allowing you to pull up on them as well as push down. As for weighting the pedals I wouldn't know how as I don't have the pedals in my hand, but I'm sure that if you were to go to the hardware store with the pedals, you may be able to figure something out. I'm sure that duct taping a weight to the "hump" side would solve your problem, but keep in mind that you are adding mass to the pedals, and it may make contact with the ground (aka pedal strike) during a sharper turn.

My suggestion is to go to your local bicycle shop and buy some platforms pedals so that you don't have to go through the trouble of modding your pedals, or have the issue of extra weight, or pedal strike. And considering that cheaper platform pedals are around 15-30 dollars, I think it's a worthwhile investment as they'll be functional on both sides, without the trouble of fabricating a weight attachment.


Tacx Flow Smart trainer calibration issues with 700x35c tyre I'm getting into cycling properly and I have bought myself the Tacx Flow smart trainer along with an adventure/gravel bike. I chose adventure/gravel over a road bike as I can see myself wanting to ride light to medium woodland trails around places like Ladybower Reservoir.

I have set the trainer up and I have mounted my bike onto it as per the instructions/downloaded the app etc.

After connecting to my phone and clicking on the 'calibrate' function, I cycle up to the designated 30kph and stop pedalling as instructed only to be greeted with an error message.

  There was an error during calibration. Please try again.

I have attempted this numerous times, each time making adjustments such as pumping the tyres up to their max rated pressure of 6.5 bar / 95 psi, and increasing the tension between trainer and tyre, however I still receive the error message that calibration has failed.

Does anybody know of anything that may be causing an issue?

Just for clarity, my tyres are 700x35c
I have also made sure the Tacx Utility app I am using is up to date.

Note: I have been receiving the error message on both my iPad 3 (a little old, I know), but also my OnePlus 3T Android phone.

Update:
I have since read a few more questions on the internet regarding people with similar issues, and I have attempted their solutions.

I released the back brake entirely to ensure that there was no extra friction slowing the wheel on deceleration
I followed Tacx's guide to set up to the letter, stating that I should find the point where, when levered down, the flywheel should only just touch the tyre, and then tighten up by 4 rotations

All of this still yielded an error...

PS. This is my tyre on it at the moment while I wait for my trainer

UPDATE 2

I actually had a momentary breakthrough!

After tinkering with the Tacx Windows 10 software, I set up my own test workout (10 mins flat, nothing special). After wimping out after 7 mins (I need to get fit, IKR!) I remembered that somebody had the advice of warming the tyres up before calibrating. This makes sense.

So I hopped back on the bike and tried the Utility app for Android and BOOM I got a readout right at the top end of green informing me that I need to slacken it off a little. Success, right?

I then tried again after slackening the tension by 1 turn and it appears to be back to the same old error fun I was having previously... Technology, who would have it?

After listening to advice from @Carel, I warmed the tyres up for 20 minutes, a lot more than I would have envisaged, and I finally got consistent results being able to calibrate more than once.

After a bit of slackening, I managed to calibrate to the centre of the green zone. I can't wait to re-do the whole process after my training tyre arrives!

A quick thank you to @AndrewHenle and @DanielRHicks for their time and help also :-)


Falcon Olympic decal Looking for help in deciphering what this decal reads?

It says Harrods (which doesn't have much to do with bicycles).
The text is a bit worn, but you can compare it to the logo at https://en.wikipedia.org/wiki/Harrods.


Convert road bike mechanical disc brakes to hydraulic Im relatively new to road bikes, i was a mtb user my whole life. So i wanted to ask if its possible to change my road bike mechanical disc brake to hydraulic disc brake. I currently have the sora r3000 brake and shifter combo.

It is possible using special convertors that have a hydraulic fluid reservoir that is controled by the cable from your brifters. Giant makes such an upgrade kit https://www.giant-bicycles.com/gb/conduct-hydraulic-disc-brake-upgrade-kit There are also brakes that have hydraylic fluid only in the caliper itself such as TRP HY/RD.
Otherwise, the same limitations I discussed at https://bicycles.stackexchange.com/a/72522/21133 apply. Shimano only.makes brifters from 10 speed above and those different cable pull ratio for shifting.


Frayed cable inside front derailleur I noticed today that my the cable controlling my front derailleur is beginning to fray. Hoping to get this great group's thoughts on the situation.
It's a Shimano 105 2x11. Bike has about 150 miles on it.
Q1: Does it seem surprising that it's happening so soon? Could I be doing anything in my riding or maintenance to bring on this problem?
Q2: How close is it to failing? If I continue to ride till it fails could I cause more damage (other than a long walk home), or should I get it fixed right away?
Thanks very much for your opinions. Picture below.
UPDATE: a few people asked for additional pictures of the assembly. Adding 2 more. Thanks.

If you are still in your warranty period bring it in to the dealer your bought the bike from and ask them to replace the cable. It is unlikely that anything you have done in normal use would have caused this. At this point it is a relatively easy fix. I have worked on shifters where the cable has been used breaking a single strand at a time until complete failure. It left a birds nest of cable ends that wouldn't pull out in either direction. If they aren't willing to fix it under warranty still have it repaired.


Handle bars don’t return My 27 year old Raleigh had the very first Rock Shox on them. I replaced with a set that cost about $160. I also upgraded the head set with a new style clamp on stem. Everything felt great until I rode and found that when I turn, the handle bars want to stay and it takes some force to return them to the straight position. I adjusted the headset so the turning is very smooth on the work stand but again the headset feels like it wants to flop to either side. The front wheel is a lot further forward than the original Rock Shox.

Your steering geometry has obviously been messed up by the installation of the new fork.

I'm guessing the new fork is longer than the old fork.

An old RockShox suspension fork would have very little (by modern standards) travel, and the distance from axle to bottom of the head tube would not be much greater than a rigid fork. Modern forks have longer travel, are designed for bikes with higher head tubes and are significantly longer. if you put a longer fork on a frame it pushes the head tube up, increases the head angle and positions the front wheel too far forward.


Why aren't most suspension bikes extremely long travel? Considering that all mid-range rear shocks have a setting to limit the travel (called oil gate CTD or equivalent?), why wouldn't most frames be designed for extremely long travel?
What is the biggest factor that influences this?

Is is it that a frame with compromising geometry between cross-country and downhill geometry (head tube angle, chain stay length) can't exist?
Is it because of the added weight?
Is it because many people ride cross-country and don't imagine they will ever enjoy rougher sections of the trail?
Maybe the price is the main reason?

Because:

Long travel bikes have a particular geometry which only benefits descends. Applying long travel on an XC geometry bike will create a bike which is not good for anything.
Long travel absorbs a lot of energy. XC riders would not like this.
Long travel requires stronger construction to avoid flex. This means more weight.


Air in oil damper of suspension fork after pulling hard while disassembling I've opened my Reba fork (FS-REBA-RL-A6) for the 1st time to investigate an air-spring failure and found the lower legs quite difficult to separate, even after not-so-gently tapping the bottom bolts.

I've pulled them hard (by hand still, so not suuuper hard) and when the shafts suddenly separated from the lower legs, the two pieces (crown upper legs assembly and lower legs) separated abruptly, with an "air popping" sound.

No oil seemed to be in there, just some drips and some grease. Maybe that's why it was so hard to pull?

Despite the non-genlte procedure I was forced to do, all seemed good. Now... since it's my first time opening a fork, I'm in doubt if I could have damaged anything.

I'm worried about the oil damper. It sounds mushy when I move the shaft in and out. Like air is inside, mixing with and creating foam in the oil.

I guess if I've pulled too hard I could have pulled air in... is that even possible? isn't there air already in normally?

The reassembly instructions in the manual, when one refills the damper back with oil, look like they leave some air in too (pour 108 mL and just close the thing). I guess it's ok but just wanted to check with you out.

Thanks in advance!

I do not have experience with the Reba, but Boxxers and Lyriks. Separating the casting from the stanchions should not be that hard. It is important that the shaft where the bottom screws are screwed in can move easily and the air can pass before you try to separate the parts. You have loosen the screws a couple of turns like it's suggested in the manual. Then you have struck the screws. That does not have to be that gentle. If one or both screws cannot be easily moved up and down slightly repeat this task by loosing the screws a couple of more turns and striking on the screws again.

In the manual it looks like it's an open bath damping, so air is in the oil chamber by design. You cannot have put more air in it by pulling the fork apart.

If the sealing between the damper chamber and the lower leg is worn out there could be that oil is lost. But this should not occur with a newer fork. And then there should have been more oil in the lower leg. To make sure you could measure the oil level. Either per oil height (but I'm not sure how accurate this is) or by removing all the oil and adding oil back - preferable by cleaning everything and using new oil. Don't remove the old oil if you do not have the right spare oil.


MTB Hardtail preventing flipping backwards on steep gradients When climbing longer 40-50% gradient sections my front wheel starts lifting even at cadences around 70. Leaning forward doesn't help much, I am already balancing myself on the rear wheel. Today the bike suddenly got out of control, I flipped and fell on my bum.

Longer stem? Saddle forward? Can you shorten the front suspension? What can I do to shift weight forward?

Here's the actual climb in question, according to OP.

So if you are out of the saddle, clipped into pedals, and have your hips to the stem and are bending forward at the waist, then there's little more you can do to balance the bike.

Consider not wearing a backpack.

You might be able to vary your track on the path by zigzagging, or taking a slightly less head-on approach.

Try the climb again, while recording on strava.  Then use the Compare function, or a link like this https://www.strava.com/segments/4354748/compare/MzU0NzM3Nzc4NSwxNTgzODc4OTU0NA==
   to compare your best segment effort to someone else's. The top time was  only doing 1.4 km/h on the really steep bit at 0.7 km into the segment.

Generally the answer is momentum, and lots of it.  And if you stop, you're stuck.

If you're there, try and watch other people ride the same track.   See how they approach the same sections and where they push hard.


How to remove a (press fit?) crank arm from a chain ring? Does anyone know how to remove this crank arm? Or if it can be removed? The bike was ~$250 and seems to have a lot of 'don't take this apart' engineering, I'd like to soak the chain rings in rust remover without the arm interfering. The interface is also just a bit loose. It's not clear if there's any way to tighten that gear-looking around the square.

Sorry, those chainrings are riveted in place. You just have to replace the whole crank arm.


Is this a collectable bicycle? I have purchased a new bicycle, it is a clasical one (downtube shifters etc). I want to use it for commuting. Some guys told me that it might be a collectable bike and maybe i should try and find a bike colectioner before ruining it as beater bike.

I have posted picture of it here.
http://imgur.com/a/ugTnS

There are good Campagnolo parts on it which may be collectible, and it is a Masi frame, which held quite a bit of value for some time. It's not in bad shape, but not so good as to justify mint condition collector value.

I doubt it has any serious value even fully restored unless it was actually ridden by Fausto Coppi or Eddy Merckx (which is understandably unlikely), but if you take the time for a restoration, you may get a couple thousand or so dollars from a collector with a particular interest in Masi.

Anything beyond that would require a specialist in the subject, and provenance on the frame.


Which saddle is suitable for me? I have a question about saddles. I bought a mountain bike 2 days ago. I thought it would be better to ride a bike rather than going on a walk in these Corona days (for exercise purpose). My bike is MOSSO Raceline 29" alloy frame. My weight is 138kg and my height is 1,95 cm. Bike shop guy recommended me this bike because I am overweight. When I ride the bike, the saddle gives me a lot of pain to my butt. I read forums, they say you'll get used to it in 2 weeks but I am not sure because of excess weight. I checked on the internet that there are some gel saddles (Selle Royal). But I am not sure which one will be comfortable and suitable for me. Please consider that I only ride on the bicycle on the road (not going mountain or unbalanced terrains), I use it like a road bike. If anyone has any saddle purchase experience can you please share it with me? Thanks for your help guys.

One cause is that you've mistaken the saddle for a seat.  The main difference is that a saddle does not hold all your weight - some amount of your weight sits on the pedals and a small amount on the hands.

By comparison, a seat holds 100% of your weight, and you could ride with no weight on the feet or hands.  This wouldn't work.

Other items that have saddles include horses and motorbikes (which have stirrups and footpegs respectively)  whereas seats are at the dining-room table, in cars, and recumbents.

Suggestion  try transferring some of your weight through the pedals rather than putting all your weight on the saddle.  The downside of this is that its more pressure through your knees, which can cause aches.

Separately, the material of your saddle is a completely personal choice.  Some people are perfectly happy with hard plastic or carbon saddle. Some people find a squishy padded saddle works best for them.

A Gel or heavily padded saddle will squish out from under your sit-bones (ischial tuberosity  https://en.wikipedia.org/wiki/Ischial_tuberosity ) and will put pressure on the softer tissues.  In more-extreme cases the padding will put pressure on your soft tissues, flesh  that shouldn't be bearing any weight.  This is one of the causes of penile numbness in males and similar in female cyclists.

Just to be clear, your butt doesn't support your weight.  Your sit-bones, part of your skeleton hold basically all your weight.

Another thought is perhaps your existing saddle is the wrong width for your sit-bones.  On a too-narrow saddle your sit bones will hang off the side, causing weight to be held on the soft flesh.  If your saddle is too wide, its not quite as bad.  There are a couple of existing questions with answers on this topic already:

Is it possible to measure your sit bones at home?
What type of saddle doesn't hurt the pelvic bone?


What does "claiming the lane" mean? If one is "claiming the lane" does that mean:

a) they simply ride on the street (i.e. on the left side of the lane in the US, Germany, France, ..) or

b) they are riding in the middle of the lane, with someone else side by side, or some other way that they take over most of the lane width? or

C) Another definition?

b) is most correct, except that you don't need anyone else by your side.

Taking the lane is riding pretty much right in the middle of the lane, and asserting control of the entire lane. Riding in the middle makes it obvious to motorists that they'll have to change lanes, or wait for a safe opportunity, in order to pass you.


What solutions are there for a tyre that won't stay seated? I've got a Schwalbe snow and ice 700x38 (also marked 40-622) on a Mavic A319 (19 mm internal width).  This, according to Sheldon should be an ideal combination (and if it wasn't, the failure modes don't match).  Other tyres seat well on the rim but this one has always been problematic: when I first fitted it last winter, and the first time this winter, the bead wanted to ping out of the hook groove.  Last night I topped it up (to somewhere in between the min and max recommended pressures), got about 10 km and it came off the rim.  After that I just couldn't get it to seat - pumping it up hard it came straight off the rim, pumping it up soft it came off within the first 10 metres.  After several attempts (over an hour in -4°C) I had to give up and call for a lift.

Other tyres on the same rim are fine (marathon plus 32, marathon mondial 35).  This tyre seemed OK on the front rim for the same bike (a 17mm Alex) but doesn't fit under the mudguard (I've got a 35mm studded tyre on there).

I'd really like to refit this tyre tonight given the weather forecast, and studded tyres are only available mail order so there's no chance of getting a replacement quickly.

Is there some way to persuade it to seat and stay seated?  Does the tube width make a difference - my spare was only recommended up to 35mm but it orginally failed with one recommended up to 40mm - perhaps by exerting lateral pressure into the seat immediately rather than radial first it was persuaded to seat but only just.

Update: I've tried it on the front wheel of my 29er hardtail.  It won't seat there either, and in a few attempts it popped off in a different place each time.  The bead feels OK, less pronounced than some of my other tyres (which are mostly Schwalbe as well) but not enough that you'd notice unless you were trying to find something.

I have had this problem with two different Schwalbe tires now. On both of these tires one of the bead cables/wires seem to have become undone. Not sure how to describe it. If each of the two beads is made up of several wires wound around each other, then on both tires one of these individual wires was poking out of the bead. It was very easy to spot because on both tires it was sticking out several inches just on the inside of the bead. No apparent length wise gash. Rather, it seemed to me as if one of wires had become unwound and migrated over time, I assume, as either a wire individually, or the whole set of wires, resulting in one wire being located parallel to the other wires but outside the tire proper.  Both wires were on the inside of the tire. Sent a picture to Schwalbe and received replacement.


Why are bicycles considered vehicles and not "walking aid"? The Bicycles.SE blog states "Cyclists are vehicles, not pedestrians.". I think most of this community, plus most of the laws agree with that.

However, a cyclist has the speed, mass and maneuverability of a sprinting person (who is, of course, a pedestrian).

Why are bicycle riders considered vehicles and not pedestrians?

a cyclist has the speed, mass and maneuverability of a sprinting person

Not really! The world record for 100 m sprint is 9.58 s, which equals 37.6 km/h, which is fast but not anything spectacular for a bicycle. The marathon world record equals to little more than 20 km/h, which is less than my average commuting speed. Going back to "human" speeds, I would estimate that an average biker goes roughly twice the speed of an average runner.

With double speed:

Braking distance is quadrupled (ignoring reaction time).
Kinetic energy = damage in case is collision is quadrupled (not even taking into account 10-20 kg extra mass & hard and sharp metal parts of the bike).


How do self-adjusting hydraulic disc brakes work? I have Avid Elixir brakes on my mountain bike.  They are the only part of the bike that's a total black box to me.  I understand the principle behind disc brakes, and I understand the principle behind hydraulics.  I could draw a diagram of how this all goes together.  That said, I've been told that they automatically adjust for wear on the pads, so as the pads wear down, the braking action is the same.  Part 1 of the question: Is this true?  Part 2: How the heck does it work?

I think the answer he was looking for was how they adjust as the pads get worn.  There is a check valve in the master cylinder, that will allow enough fluid from the reservoir when the lever is pulled.  If more fluid is needed because of pad degradation, it passes it into the active system.  Therefore with more fluid in the system, the piston is pushed out slightly more and the pad is the same distance from the rotor.

That is why your res. needs to be topped off occasionally.


Is it possible to repair a dent on frame? Hi, I found today dent on down tube (13/14cm from head tube).

I have two questions:

Is it possible to repair the frame?
Is it safe to ride the bike after this

Main frame is aluminum.

The dent is on the right side of tube and it's only one damage that I found. I bought this bike a time ago, but usually I store it in dark basement and didn't seen it before.

it could be fixed cosmetically, but not structurally.

but it's not recommended to fix it, bending it over and over will cause more and more Metal fatigue. and it's a hassle to do so.

about safety, most named brand is "ok to ride" under this condition, but there is luck involved. so it's a good idea to replace that.

why I say luck - all frame are slightly diffrent, even they look the same. some will break faster, some will hold on like it was nothing, and each rider's style will change the parameter. so no one can precisely predict the outcome.


Shimano Claris shifter double/triple shifting up (when moving to smaller, harder cogs) on the rear derailleur Although my rear derailleur is properly indexed it's suddenly started to double or even triple shift on an upshift - i.e. when moving to harder, smaller cogs on the cassette.

This happens whether I'm riding or even if the bike is completely stationary and I'm only moving the shifter in isolation - I can feel and see the display on the hood jump 2-3 positions.  It only happens in what would be the mid positions of the cassette - the very bottom gear and the top few gears aren't affected when I shift up from them.

Downshifts to larger, easier cogs are completely unaffected.

I've tried peeling back the brake hood and giving the mechanism a good blast of penetrating lubricant but to no avail.

Is this likely to be a shifter only problem and what if anything can I do to rectify it?

Check the following:

If you remove the cable tension, do you get the right number of clicks for the shifter? If not, you may have a broken pawl or gummed up pawl. If blasting with wd-40 doesn't work, you need to get a new shifter, cause taking apart a brifter and putting it back again is hard.
Is the derailleur bent? It isn't possible to adjust a bent derailleur satisfactorially. To unbend it properly, you need a special tool.
Is the chain worn? If so, get a new chain. Check with a gauge.
Is the cassette worn? If so, get a new cassette. And probably a new chain, for good measure. See this link on chain + cassette wear.
Is the derailleur adjusted properly? The cables do slip over time, and you may need to readjust them. Follow the directions here.
Is the cable slipping or have excess friction or under too much or too little tension? You can clamp down the cable and/or replace it. You can also get weird things if your frame flexes enough to pull the cable, e.g. if you have under-bottom bracket shift cable routing.


What inner tube size to get for my road bike? I want to get some spare inner tubes for my new road bike, but I'm unsure what size to get. On my tire it says the size is 700 x 25c and I know that 25 is the max width of the inner tube. So should I get 700x20-25c or 700x25-32c? I'm guessing 700x20-25c would be the safer option, correct?

As long as it is in the range you are good.  You can even cheat outside the stated range a bit.  Too big and you can fold.  Too small and you stretch.  If it is spare you are going to carry on the bike then the smaller.


Pedal on exercise bike fell off, not going back on My pedal came off my exercise bike/cross trainer. I have tried putting it back on, but the big screw will only go in so far.  It is turning twice then getting stuck. Can anyone tell me what I need to fix this. I don't know the names of the certain parts etc to search myself.

Which side pedal came off? This answer might help, pedals don't both screw in the same way.

If not, can you attach a photo? If you don't know the names we can help figure it out for you.


What can I add to a chain cleaning bottle to get between the links? Every so often I take off my chain to give it its most thorough cleaning - the shake it up in a plastic drinks bottle with a bit of degreaser method. This works pretty well, and I've added some bits of cut up plastic scouring pad in there to help, but there are always lumps of gunk left on the insides of the link plates even after the most vigorous of shakings. I generally get those off manually, but end up redistributing some of it back into the chain no doubt.
I've been thinking that if I was to add some little balls of perhaps 2mm diameter, they would work through between the link plates and knock off a lot of trapped gunk during the shake. Question is what to use: steel bearings might be too hard and potentially leave fragment of rustable steel behind. Ceramic balls? Sugar balls!? A dense plastic? If it's something that breaks up, obviously it mustn't leave anything behind. Do I need something with a lower Moh hardness value than steel? Anybody doing anything similar of have any suggestions?

I am not sure that any of the additives that you mentioned are necessary. You already have fluid flushing through the open spaces of the chain. I'd recommend just changing your degreasing solution and shaking the chain again, several times if necessary.
In addition, dirt between the link plates may not matter as much. Most friction is generated between the rollers and pins. If you were looking to totally optimize your performance and chain life, you'd need to get the dirt and old lubricant flushed out of that area, not just between the link plates. Repeated washing in a bottle appears to be sufficient to remove most of the contaminants from between the rollers and pins (demonstrated below), and it should suffice to get dirt out from between the plates.

Parts of a chain

The image above is courtesy of the blog Bike Gremlin.

chain link
inner plates
roller
pin
outer plates

As I mentioned, the majority of chain friction occurs between the rollers (#3) and pins (#4). Also, our chains wear as dirt gets between these items. In conjunction with lubricant, this forms a grinding paste that erodes the rollers. Thus, you ultimately want to minimize the contaminants that get between the pins and rollers if possible.
Cleaning your chain
It is not necessary to remove your chain to clean it. Per this Cyclingtips article, most riders should find it sufficient to a) wipe their chains with a rag after each ride and b) periodically use either degreaser and brushes or an on-bike chain cleaner as described by @Mr_Thyroid in comments.
If you are determined to clean your chain more thoroughly than this, I'd recommend watching this video by Josh Poertner of Silca. He does demonstrate why a degreaser and brushes is inferior to shaking the chain in a bottle of degreaser. In his demonstration, he showed that 4 solvent changes in a bottle produced a very clean chain, which he described as nearly equal to an ultrasonic cleaner. Again, if you are determined to use a bottle and solvent, simply change the solvent as often as you feel necessary.
NB: He created this video as part of an instructional series for Silca's wax-based chain lube, which requires every bit of petroleum-based lubricant to be removed from the chain before application. You don't need to buy his wax lubricant. You should merely take his broader point about chain cleaning. My read of the video is that he didn't consider an ultrasonic cleaner vital for the purposes of applying wax lube. That implies that for general purpose cycling, multiple agitated solvent baths should be a very good solution.
Now, if you are deathly determined to extract every last bit of gunk out of the chain, by all means, consider buying an ultrasonic cleaner and finishing your chain cleaning in there. Remember that this is not necessary for almost all cyclists.

Some miscellaneous comments: new chains come in a cosmoline-like substance to protect them from corrosion. Some argue that this substance is an excellent lubricant, and should not be removed. Others argue that the factory lubricant is high-friction and is excellent at absorbing dirt from the environment. It strikes me that allowing the chain to soak for a few minutes could help dissolve the grease, if any is left on your chain. However, beware that many citrus-based solvents can cause embrittlement of the metal, as discussed toward the end of Poertner's video. Basically, do not soak your chain overnight in a citrus-based solvent.
Also, you may be aware than many quick links are not rated as reusable. Consider how much force you have to exert to close many 11s quick links. While many riders including myself have re-used our links without apparent issue, it is best practice not to do this if the link isn't designed for it. I would expect that the link gets weakened with each use. The more you clean your chain off the bike, the greater the likelihood of an unexpected failure.
To my knowledge, Yaban (YBN) rates their links as re-usable for 5 times, and Connex has no specific upper limit. Some KMC links are reusable, but some are not; check the package. I have personal experience with 11s Yaban and 10s Connex links, and I believe either would be a good purchase if you are set on frequent agitated solvent cleans.


Are there any downsides to cheaper biodegradable degreasers? I’m after a cheaper (than the bike-specific brands) biodegradable degreaser for cleaning my bike chain.

I have found a few which are apparently biodegradable, however, I’m wondering if there is anything about non-bike-specific degreasers that could cause any damage to the bike?

I use a generic citrus degreaser from Home Depot (largest home improvement stores) that costs $2.99 a bottle. Works fine, does not damage the bike.


What's the better option to buy? I am about to get myself a hybrid bike, but being tight on budget (~ 200USD). I didn't really have many options to choose from. I'd initially thought of buying this particular bike, Mach City Munich after reading good reviews about it online, but it's been unavailable for the past month, without any surety about when it will be.
So, the shopkeepers suggested I get myself another bike, named Montra Downtown.
I live in a city where roads have potholes and bumpers more frequent than lighting poles, (but not the kind that'd require an MTB).
The bike will primarily be used for commute (~15 kilometres, 6 days a week), but I'm also thinking of taking it out for long rides (about a hundred kilometres or so) on weekends.
Both of them have a triple chain ring system.
Downtown has an alloy (6061) body with a steel fork whereas Munich has both the body and fork made of steel.
Both of them have a 21 speed system with triple chain ring system.
Downtown has Shimano TY300 whereas Munich has TZ40 rear derailleur.
Munich has Shimano TX 50 where Downtown has Shimano TX 500 front derailleur.
Both have Shimano easy fire shifters with integrated brake levers, with Munich having a three finger braking, and Downtown having a two-finger.
The brakes, however, on Downtown are disc brakes, whereas on Munich are V brakes.
The cassettes on both are the same too.
Downtown mentions BB Cartridge-Sealed Bearing-Cold Forged Boron Axle, Plastic cups, Steel Body for the bottom bracket whereas nothing is Mentioned for Munich.
I've never ridden a bike with gears as of yet, this will be my first time.
I'm confused between which one to buy for a multitude of reasons. I've been told that a steel body has a give, it flexes, which allows for a more comfortable ride in a place that has roads that aren't very smooth, which does not happen with an aluminum (alloy) frame.
I've heard that disc brakes are harder, require a lot of maintenance and are more expensive to maintain compared to V brakes too.
Downtown has alloy rims, double walled. Munich previously had "double walled rims" specified but currently their website only says that the rims have an ED black finish so I'm not sure if they still have double walled rims.
The bike will most likely be stored about two storeys high, where it'd need to be picked up and carried through the staircase.
And last, but not the least, the cost of Downtown is about 20% higher than Munich. (both are in the budget nevertheless).
If I buy Munich, is it a good idea to swap components and use? For example, the rear derailleur?
Moreover, since I've chosen to buy a rigid bike (because my limited scope of knowledge tells me that a suspension frame with such a low price tag will only be a pain), is adding a suspension seat post a good idea?

Ultimately, you're comparing two entry level bikes.  The differences are small and mostly irrelevant.  The one thing that really matters is how they fit you - ride both and figure which one is more comfortable to you.  So bare minimum is to get a leg over each one and ride it around.
Most bike shops will let you pedal around, which is enough to rank them in immediate comfort.  If you're buying online, then you're stuck and have to make the best guess you can.  This is one reason for buying from a real LBS and not a boxmover.

This question is pure shopping and is off-topic for Stackexchange, because there's virtually no chance of this question being useful to anyone else.  For example, neither of these bike brands exist in my area.
The transmissions are Tourney grade, which is shimano's second bottom groupset in terms of cost or quality.  It will work fine, but comparing variants is like comparing pebbles in a stream - in detail there are differences but up close, they're all much the same.
And no, if you were asking about expensive top-end bike comparisons, that would still be off-topic.


Giant Road Bicycle, Comfortable Seat Anyone know of a comfortable seat that is compatible with Giant Bikes?  I took my seatpost to walmart to try and fit the seatpost with the bell gel seatpost with shock absorbers, Had high hopes for this one but the two rails did not line up with the bracket on my bike.  Trying to cut down on the impact from bumpy roads..and I already have biking underwear.

Almost all seats and seat posts use a standard width and size rail.  Unless you have a very high end setup, it will be compatible.  Since the one that you described didn't fit, I agree with the previous posters that the LBS has got it wrong somehow.

Note that padding is not the only way to reduce saddle pain: getting a saddle that fits is much more effective.  If the saddle is too narrow for your sit-bones, or too wide, then no amount of padding will make you feel comfortable on it.  That's got nothing to do with the size of your .... um ... ass  ... rather, the saddle width has to match the bones of your pelvis.  Some bike stores have a little gel ruler that you sit on and it measures the distance, thus allowing you to choose a saddle with the correct width.


Shifter with stuck barrel adjuster I've been looking for a solution on this but couldn't find anything online. I have an Alfine 8 speed internal gear hub and it started skipping recently. I tried to use the barrel adjuster on the shifter to adjust, but the barrel adjuster got stuck and it won't turn in any direction anymore. Is there a way to fix this? I can still pull the barrel adjuster slightly (as if I am about to make an adjustment), and can turn in both directions a couple of millimetres, but it does not go forward more than that. Can I solve it by any means or should I just replace the shifter? This is the shifter by the way:

http://www.amazon.com/SHIMANO-SHIFTER-SL-S503-ALFINE-2100mmCABLE/dp/B00KV9SJ2Q/ref=sr_1_16?s=sporting-goods&ie=UTF8&qid=1460402799&sr=1-16&keywords=alfine+shifter

Thanks!

You can install an inline cable adjuster. There are several companies that make them.


Vintage Sealed Hub Maintenance Questions Trying to do hub service for the first time...

I have removed the locknuts on both sides. I'm checking to see if I should be able to hammer the axle out because it's firm.
Is there supposed to be a seal on the drive side? Because there was none.
The seal on the non drive side can be safely removed how?

First, don't hammer anything, yet.

Non-drive side looks like a sealed cartridge bearing. On the drive side you have a freewheel unit that screws on. You'll need to get that off before proceeding further I believe. The drive side bearing is located at the inboard side of the freewheel, which is why you are not seeing a seal.

Park Tool has a pretty good video on freewheel removal that helps you find the right tool for your particular freewheel.

Next steps depends on what you want to do, either re-grease or replace the bearings. Either way you can find YouTube video how-tos. Try this and this from Global Cycling Network.

If you you want to remove the seals on the cartridge bearings to re-grease, the seal can be very carefully prised off with a thin sharp object such as a box cutter blade.


Shimano Nexus 3 (SG-3C41) 2 and 3 gear problem - Ring Gear Unit Repair I have this internal gear hub and i try to fix it. 1st gear is ok. On 2nd and 3rd gear, especially when I run faster, the hub is not engaging properly, missing engagement sometimes. It is not problem with chain and/or with sprockets.

I`m pretty sure that the problem also does not stem from shifting mechanism.
I removed clickbox and operate pushing rod manually. I understand how it works internally because of numerous disassembling and greasing similar hubs. I pushed rod till the indent on it to engage 2nd gear and till the end to engate 3rd gear and especially at 3 i feel that gear is alternating between  1 and 3, making some noise.

This bike was heavily used and i suppose that Ring Gear Unit (no. 5. here), namely,  cogs that are "opened" by the driver are worn out and/or circular blade has malfunction and does not support and "lock" that cogs properly.

My question is how to assure that only Ring Gear Unit need to be replaced and how to check if hub exterior is ok.
I`m not sure how to check that Carrier Unit (no 4) is ok. It is used by 1st gear, and that gear works properly, so it suggest that this 4 small gears are ok - they look fine.  Not sure if it "as designed" - they can be pushed towards centre of unit, when whole unit is off the hub - fell like holes in them are broader than rods that rods that secures them in the unit. This unit also engaged in 3rd gear and that gear works noticeably worse than 2nd (ie loses engagement more often than 2nd).

My last idea is to "fix" rods of unit 5 by "sharpening" them a bit with a file. Is it a good idea?

UPDATE photos & experiments

Cogs looks like that:

Hub housing from inside (a bit of damage can be seen):

for test I reassembeld hub as follows: I've removed part no 2, 3 and 4 and put the rest into the hub. I got 1st as free gear and 2nd and 3td, both equal to original 2nd gear. I got the same behaviour as described before - mis-engaging at higer speed. Former photos suggests, that part no 5 needs to be replaced. My question is: is it worth to replace it without replacing hub housing (photos show minor wear of internal structure)? Is it possible to get just two cogs, without whole Ring Gear Unit (I mean new one, not second-hand). Last question - which surface of the cog(interior or exterior) would you suggest to file off to try to make it working properly? (since it`s rubbish, i can try :) )

UPDATE -I've added my solution as answer.

The question - is it possible to buy cogs separately and what shimano say about: "when to replace stuff" is still open.

After a bit of thinking I filed off cogs from the outside. So far so good, hub presents good enegagement at all gears. After few weeks it still runs good. Left is "fixed", right shown for comparison. I fixed (filed) both. Be careful to make them equal shape and that sharp border is not too thin and ortogonal to the side surface


How to make old bike's seatpost slide smoothly when it needs adjustment again? I've several old bikes with a common problem, the seatpost is a bit too much hard to slide just to adjust the height (sometimes the frame scratch the seatpost), which might be ok on a road bike, but not so much on MTB or folding bike, when you need to put the bike in a car for example. I thought about sanding both the seatpost and the inside of the bike, but is that a good idea? Of course I grease the seatpost to avoid galvanic corrosion and let it became stuck over time, but it slighty improve, doesn't solve the problem.

There are different things that can cause this problem and different tools and techniques that can be used to fix it, depending on the cause and severity.
Frame material cannot be left out of the conversation. Between steel, aluminum, and carbon, the problems and acceptable solutions are all different. Carbon should usually be approached with elbow grease and appropriate chemicals only, aluminum may need that plus material removal methods, and steel may need any of the above plus the full range of more metalworking/manipulation type fixes.
The problems that can potentially exist, from least to most severe, are:

A seatpost that's either out of tolerance or the wrong size.
Corrosion.
Burrs and other slight high spots in a frame that's never received basic honing.
More serious dimensional/distortion type problems left over from manufacture.
Acquired damage, the most common situations being seatpost binder "ears" that have become distorted inward from being forced to clamp an undersized post, or that have folded out and/or rippled from a post being ridden with inadequate insertion. (This one is mostly exclusive to steel frames. Aluminum will tend to either crack or break instead of taking a set if abused in this manner, and carbon will only crack or break.)

Of these maladies:

If it's the seatpost's fault, which isn't common but does happen, it should probably just be replaced if it can't be lived with. If you use a hone or reamer to enlarge the bore to accommodate a post with bad tolerances, you could run into problems getting any future replacements to hold right. That said, there are times when the advantages of doing the quick and dirty fix might win.

Corrosion needs to be cleaned up, ideally with something that won't mechanically enlarge the seattube bore, or at least not in any appreciable way. Doing it chemically or with light sanding is fine, as is appropriate for the frame material. (For the most part, don't sand or abrade a carbon seattube bore unless you really know what you're doing, and likely not even then.) Most shop mechanics would start with a flex-hone (see below) if confronted with a nasty looking bore on a steel or aluminum bike. They are capable of removing material, but won't instantly take a snug fit to a loose one.

Metal frames really should be hit with a flex hone at least once in their lives to take down any burrs or minor tight spots leftover from manufacture. Shops have these tools. Barring access to one, sanding around the seat cluster wherever your fingers can find potential sharp edges is acceptable as well. In some cases using tiny files to create a bevel at the slit/binder area is needed. Removing the binder bolt, sliding in sandpaper, and doing a shoe-shine motion can work too. The nice thing about flex hones is they deal with burrs and high spots it can be troublesome to otherwise see or get to, like from seatstay vent holes. Unless something weird happens, all of this is only necessary once in a bike's life, and will not be any kind of acquired problem. The default is to assume carbon frames need none of this, although in practice they sometimes do in a very targeted and judicious fashion, but only by hand.

A flex-hone

In some instances, on metal bikes only, a seat tube reamer can be an appropriate tool to solve this problem, but it's not the go-to and is a seldom-used tool even in most shops. Reamers are cutting tools that clear a seatpost-sized path down the bore. They remove material relatively freely and in contemporary times are primarily used by framebuilders to correct heat distortion, or in shops to address distortion left by the factory. Sometimes they have a role in fixing acquired damage to the bore, but usually this is limited to smoothing things out after other manipulation has been done to deal with most of the interference. Even then, assuming cold work only, the ideal goal of this kind of repair is to finesse the fit close enough that a hone does all the smoothing needed, i.e. you've gotten things so the post slides in but with some minor roughness. If you go to the reamer, you're making judgment calls about how much material the frame can lose safely and how much you'll be taking, neither of which you know. Reamers are not to be understood as a one-stop fix for reforming the bore after damage. Reamers are also capable of completely destroying the seatpost fit, and of getting damaged themselves if used inappropriately, so it's important to be judicious with them. Reamers can leave sharp edges, especially when their use was warranted in the first place, and should usually be followed by honing.

An adjustable seattube reamer

On steel bikes, sometimes the seattube bore acquires damage that can be fixed with metalworking tools and techniques. How to address this and what's appropriate for different frames/designs could be its own question. One would take different approaches on a thick-walled beater where you're willing to damage the paint and wind up with surface irregularities versus a vintage road bike restoration, for example. But, for the common situations of either crushed in or folded/rippled out openings on a utilitarian sort of bike, it usually comes down to working it back into shape with some combination of dummy posts, soft hammers, etc, with honing and possibly reaming as a final step. There are more framebuilder-level type approaches that would be appropriate on lightweight tubes or if you wanted a better looking result, and repainting would be involved then.

Before any kind of heavy cleaning, sanding, or cutting is done on the seattube bore, it's good to put a rag or paper towel down below where you'll be working to catch debris so it doesn't get in the bottom bracket area. Fish it out afterward with a spoke or small parts grabber.


Chainring bolt stuck in 105 FC 5800 chainring See my update at the bottom of the question
When installing my 4 bolt Shimano 105 FC 5800 chainrings on a modified FSA Gossammer Crank (TEAM ZWATT ZPIDER)  I first test fitted the chainrings with some chainring bolts I thought were compatible (they fit just fine into the threads, but theyre a little bit too short in hindsight).
I need to mention that the chainring bolts thread into the outer chainring directly.
I then put the chainrings on and screwed the chainring bolts into the chainring, not very tight but "hand tight".
The bolts were left there over night and aftering the correct ones this morning, I cannot get the bolts out.
I stripped two bolts trying to get them out but they just wouldnt budge, so now I'm left with a crank with two stripped bolts.
Now: the chainrings are somewhat disposable (I can order new ones but) but the crank is not, so I played with the thought of just sanding/drilling the chainrings out of the crank and this time mount correct parts. But do I have any other options at this point ?

Update:
I have sanded down the securing part of the chainring bolt using a dremel, at the cost of scratching and ruining the inner chainring.
Since the bolts were not per se stuck but have rather dug themselves into the inner chainring they sat quite loose in the outer chainring and could be undone by hand.
But in case they were stuck I believe the protruding part of the screw can be grabbed with a pair of pliers and be used to remove the rest of the screw from the outer chainring.
The cost of the whole operation was one set of chainring bolts and the inner chainring.

The bolts are sacrificed - they'll be for the bin once you get them out.
Since they're only finger tight it could be crossed thread, or possibly bad tolerances.  Could also be brand new threads somewhere with poor cleanup leading to galling, so some assembly paste might have helped.

Start with simple things before breaking out the leverage bar.

Warm the chainring/spider/bolts area with a hairdryer (ie warm not hot) or leave it in bright warm sunlight for a couple hours.
Put down a drop cloth then add some penetrating oil around the bolts.  Leave it for 8-12 hours and repeat for a couple of days.
Now try your tool and see if they come loose easier.

Since the fitment is stripped, you may find another tool fits better.  An old flathead screwdriver can sometimes be used as a chisel to force a slot.  Same goes for Torx/star drivers - they are excellent at cutting a channel with some hammer blows.   Expect to break/damage the torx bit.

Another option is to use a Dremel and a cutoff wheel to cut a slot into the chainring bolts.  Then the big flathead screwdriver has something to fit into.  Risk of damaging other parts.

If the shoulders of the bolt head are visible, you might be able to get some pliers on the sides and undo them that way.

Sometimes two clean dry fingers/thumbs will work - one either side pushing together may rotate them.

Getting more brutal, you could purchase an "easy out" screw extractor kit.  To use these you need to drill a hole into the bolt and then reverse an extractor into the hole which will eventually bite and unscrew the bolt.   https://en.wikipedia.org/wiki/Screw_extractor

Nasty time - you may be able to weld a bolt into the stripped bolt to give you something to grab.  Personally I've never had success doing this.

Last resort might be to put a chain on the bike and then pedal about the yard, not a road.  Stay firmly seated!  Ideally this will produce enough rocking motion to back out the bolts, at least enough to slot or to grab with pliers.


How can you find parts for a discontinued bike - in this case, a 2004 Specialized mountain bike I'm looking for the rear shock link for a 2004 Specialized FSR XC. Specialized doesn't have them; and so far I haven't been able to find that link anywhere!

Can anyone guide me in the right direction in finding parts for discontinued bicycles? Where should I be looking for parts?

First, try looking for a "scrap" FSR to salvage the linkage from.

Second, BETD have produced aftermarket suspension components for various Specialized, GT, Kona etc designs. They might not have the item you need in stock, but they should still have the files and machinery necessary to make one for you, at a price. http://www.mountainbikecomponents.co.uk/specialized-fsr-04-06-linkage

If you can find some engineering workshop near you, they might be able to copy your damaged linkage. A basic non-adjustable linkage should be achievable using any 3-axis mill.


Can this frame be saved? I had a little accident and went over the handlebars.

I'm okay, I was able to ride the bike home, but it is obviously bent. Everything else on the bike seems to be fine, the wheels are true and rides is straight still.

Where can I take this to get it fixed?

The frame is 100% trash.  Do not attempt to use it at all.

What you can do is to carefully remove everything from the frame.  Discard the frame, and now you have a whole bunch of valuable parts.  You can either buy a new (possibly second hand) frame, or just sell the parts to finance the purchase of another bike.

There are a few parts you won't be able to easily remove, such as the headset and the bottom bracket, but these are not very valuable anyway, so don't worry about buying the special tools for those.


24" MTB Crankset Truvativ E300 3.0, 42/32/22 Right arm replacement? I just got a Marin 24" MtB the right crank arm is about 1/2 stripped from the pedal not being fully tightened before riding.
I tried doing an internet search and I only see left crank arms.  is it possible to use a left side on the right drive side?
Not sure what the numbers mean  42/32/22 ?
I think the arm lenght is 165
I was hoping that 1256A1 would be a good part number to find the right crank arm.  I am pretty sure this is a 3 piece crank.  not definate as this is new to me.
I saw some videos on retapping the threads .. i have a tap and die set i borrowed from tool library but the videos suggest special "bike crank" taps.  I dont have a vise either at this point in my apartment.
is there a safe way to get the crank arms off without a puller?    when I was young  bikes didnt need all these special tools.   wow! things change
thanks

Fitting a helicoil or thread-replacement is the correct fix, or the whole crankset needs replacing.  From your photo, the right-side crank arm and spider are one part, and it may be rivetted onto the chainrings.
Sadly, thanks to some poor historical choices, the thread of a pedal is a weird combination of 9/16" diameter, and 20 TPI, where the common industry standard is 18 TPI.  Thus, the taps and coils are specialist to the bicycle industry and are therefore very expensive.   And additionally, the left-side pedal is left-hand thread, so the tap and inserts are all duplicated.
I'd bet that your tool library tap set won't have the required items unless its a specialist bike set.
Even having the 20TPI parts isn't enough - making the pedal thread bore at right angles to the bike is also critical, and the accuracy required is too much for a bench vise and a hand drill.  You'd need a vertical mill ideally, or at the very least a rigid pillar drill/drill press.

Your cheapest option might be to look for a donor bike.


How to ensure all muscles are engaged when pedaling Forgive me if this is too subjective, however, I've been doing some mtb riding and noticed that it's always my glutes that fatigue first especially on climbs, talked over with my friends and they tell me it's the last thing to go.
I'm wondering am I spinning too low a gear or perhaps pushing instead of making circles. How can one ensure they are engaging all muscles through the pedalstroke?

Striving for an objective answer, I would avoid venturing into the "get fitter hurr durr" types of answer.
Muscle engagement on the bike is very much dictated by various parameters including seat height, saddle fore/aft, crank length etc. You would find that lowering/heightening your saddle by an exaggerated amount engages different muscles and consequently causes pain.


Is it practical to wear motorcycle half helmet for road cycling? I am considering buying a motorcycle half helmet for cycling. I ride road bike for leisure. I would ride alongside with traffics quite often.

First of all, I am looking for more protection. I am not sure can ordinary bicycle helmet provides enough protection for lateral shock if I hit the ground.

Secondly, I really like the retractable shield. I wish to protect my eyes from UV and dirt. However, I cannot wear googles as I am shortsighted. Bicycle helmets with shield are even more expensive then such motorcycle helmet.

Is it practical to wear such helmet for road cycling? For example, are there heat, comfortability or sight blocking issues?

Firstly, to answer you question - no, it's not practical for me.

Since this is a question of personal safety, no-one can make your decision for you. So in the rest of this answer I will try to set out the issues. It's fair to say that the issue of cycling helmets has been contentious in the past, so I'll give a recap of that. I say in the past because most Western countries have laws requiring cyclists to wear helmets. The contention now comes from small numbers of die-hards (pun intended).

Legality

Firstly, you would need to find out if it's legal to wear a motor-bike helmet on a bicycle. Most (western) countries Australia and New Zealand have laws requiring cyclists to wear helmets that are approved for that use (thanks to @7thGalaxy for the correction). The approval process usually involves the local national standards and testing bodies. Before a helmet can be sold as a cycling helmet is has to go through an approval process.

I would expect that a motor-bike helmet would not have been approved for use as a cycling helmet.

Protection

The purpose of a helmet is to provide head and brain protection in the event of impact. Bicycle helmets are designed with a harder outer shell and a softer crushable liner. The outer shell protects the crushable liner from the wear and tear of regular use, and resists abrasion should your head be sliding along the bitumen pavement. Without the shell the liner would quickly wear through, exposing your head to the road. Some very cheap helmets omit the outer shell.

The crushable liner has been calibrated absorb the shock of impact at cyclist speeds. It absorbs the impact by deforming; the peak forces are absorbed and are not transmitted to your skull and brain. This is why helmets must be replaced after a crash.

The motor-bike helmet protection system will be calibrated for higher impact speeds, and so will give little brain protection at cyclist speeds.

Safety

There are two sides to safety. Firstly, is the product safe to use?

Safe to use primarily means not impairing the cyclists vision or hearing. From your image it is not clear how the motor-bike helmet performs here. But it will certainly be heavier than a bike helmet, making it harder to turn your head frequently.

The lack of ventilation also means that your head and brain could be subject to higher than normal temperatures. The evidence is clear that when the human brain is too hot it does not function as well, especially in decision making. My recollection is that it leads to riskier decisions.

Now we get to the main point of contention. The research is clear that if we provide people with safety equipment then on average they take more risks. It is very politically incorrect, but there is good evidence to suggest that helmets have done nothing to improve cyclist safety. Proponents of this view argue that any improvements in safety is due to better roads, better laws, better driver education.

That argument means that if you feel safer in the motor-bike helmet, then you are more likely to do more dangerous things. The road is dangerous enough as it is; don't add to your own danger.

Comfort

The helmet pictured is black and has no vents. It will be hot and uncomfortable to wear.

Style

None. But that could be an attraction to some :-)

Conclusion

On every perspective I can think of, my advice is don't do it.

But you have to decide.


How can a recumbent tadpole trike brake three wheels with only two levers? So this is probably a terrible idea, but I was looking at recumbent tadpoles recently and it just clicked. I would have two brake levers but three wheels. I would need to have to...

1.) Calibrate the two front brakes off of a single lever which I suspect would be maddening

2.) Only brake using the back wheel and one front wheel (turning when braking sounds like a bad idea)

3.) Forgo braking on the rear wheel since on bikes the front wheel does most braking. I suspect this is similar for trikes. I would instead be able to actuate the brakes on the left wheel with the left lever, right wheel with the right lever etc...

So, the question is, what is the general brake setup for tadpole trikes?

Most are set up with one lever that works two brakes at the same time. There are lots of different styles, such as this one for example.

You can see that it has 2 ferrules instead of 1, most commonly used on dual disc brakes. There are other models that differ somewhat visually but the idea is the same. Many Trike levers also have a push button locking mechanism that functions like a parking brake so that it cant roll while engaged.


Mechanic and top rider's bike on right side of team car - why? During the 2017 TdF one of the commentators said the that a teams GC contender or their best rider always has their spare bike carried on the right side of the team car, on the roof, above the team mechanic.

This was surprising and I'm wondering why the top rider's bike has a special place.  Is it just because it's fastest to grab a bike thats directly above oneself in the case of a mechanical failure or are there other reasons as well?

Yes, the idea is to have the quickest bike change possible for the person it matters most for.

With the bike attached on the same side as the mechanic's, he just opens his door, turns, and grabs the bike. For any other bike, he either has to go around the car, or even remove another bike before getting to the one he needs.

As for the obvious followup question (why is the mechanic on the right-hand side of the car?):

In case of mechanical trouble, riders and their support cars should stop on the right side of the road. That makes it easier for the rest of the race and other vehicles to avoid the obstacle. (This was actually part of the problem for Richie Porte and his controversial wheel change at the 2015 Giro d'Italia.) Of course, if there is a crash, the support cars will stop behind the crashed rider(s) to protect them from traffic.


Sore/inflamed fingers after cycling I consistently get soreness/inflammation in the knuckles of my right hand the day after even short rides (e.g. 16km yesterday, with a ~2h break in the middle). Bike is a Scott Speedster with Tiagra 4500 STI levers.
Applying some mechanistic reasoning (and from the feeling in my fingers when I'm foolish enough to ride with them still slightly inflamed), it's likely to be from shifting to the larger cogs in the back. I realize that modern levers are supposed to be lighter to shift and therefore older ones require more force and this could be a contributing factor, but I literally cannot find a single other complaint like mine online. All I'm able to come up with is complaints about hands/fingers tingling/going numb. At this point I figure it's either bad technique or bad equipment, am I missing other possibilities? How do I tell which one the problem is?

Sounds like you are shifting at a bad/uncomfortable angle, need too much force or your hands are just not used to the work. Are you sure it’s not from braking or your hand position in general?
I had problems shifting after I injured my middle finger while climbing. What helped most was using as many fingers as possible for shifting (in both directions).
When you are on the big chainring you generally need more force to shift on the rear derailleur. So I’d try shifting to the small chainring earlier (which also means less work for the right hand).
You could install new, good cables and cable housing to reduce friction. In my experience good, properly routed cables make much more difference for quality and ease of shifting than the price/tier of the groupset.
As a last resort you could change to a different type of shifters. Either twist-grip shifters, bar-end shifters or electronic STI shifting (Shimano Di2, SRAM eTap), though it’s very expensive.