16

Saddle height for new bike setup purposes should always be set relative to the pedal, not the BB center or any other reference point. So yes, crank length makes a difference. Using the ground or BB center as a reference point is convenient for re-establishing a given height after the post has been moved, but not for setting up one bike to have the same leg ...


16

I started getting seriously into bike work circa 2002 and was lucky enough to come across Jobst Brandt's view of the topic around that time. Since then, most of which time I've spent working as a mechanic, I've observed that the Brandtian observations of the mechanical dynamics at hand are wholly correct, but I don't agree with him on what to do about it. He ...


11

Many two wheel drive mountain bikes exist. Here's one article advertising a new one: There’s been no shortage of attempts to build a workable two wheel drive bicycle over the years, but this latest effort from Double of Japan looks like one of the most compelling yet. https://www.bikeradar.com/news/this-is-a-two-wheel-drive-bike-done-right-sort-of/ They do ...


10

There is little research on the impact of crank length on power output in cycling. There are some lab studies, and they seem to show that even for crank lengths significantly shorter or longer than the norm, the metabolic cost to maintain a specified speed or power output in the lab doesn't change. Importantly, some of these studies included lengths ranging ...


10

You are undertightening the crank bolts on initial installation. 44Nm or 33 ft-lb work well as generic values for square taper cranks. A basic large beam-type torque wrench works well for crank bolts. If you aren't able to get one, it's safe for basic square taper cranks to reef like mad with something like a 12" ratchet or breaker bar. You'll be ...


9

We can't tell you what upgrades you should make, because we are not you. We don't know what your preferences or priorities are, what kind of rider you are or what riding you want to do (apart from knowing you have a long distance goal in mind). Go ride the bike. Make a training plan for your long distance ride. Go ride the bike more. Figure out what works ...


8

You could replace the crank with any Shimano 2x9 crank for a square taper cartridge bottom bracket (with the same chainring sizes are crank arm length or course). If the bike is equipped with an Altus groupset then an Altus 2x9 crank would be a reasonable choice. There is a bit of an annoying wrinkle to this, different square taper crank models require ...


7

This is "older" advise that used to be gospel but these days has been engineered to be less of an issue. The chainrings and cassettes are constructed in opposite directions. That is the big chainring is on the outside, and the big cog in the rear cassette is on the inside nearest the midline of the bike. Upshot, when your chain is on "big-big" meaning the ...


7

You stated that your frame is a Wilier Imperiale. I'm not certain what year this applies to, but it is very likely to have a proprietary bottom bracket standard known as the BB94 or BB93 standard. Per the Cyclingtips link: Wilier designed its BB94 (later re-named BB93) around Campagolo’s Ultra-Torque cranks. Seats for the bearings were moulded into the ...


7

It depends. For most gravel bikes it will be an easy, yet expensive, swap. A couple of gravel bikes frames are built in a way that makes shipping a front derailleur as good as impossible. There may not be enough room for the chain stays to clear a second chain ring. What is more, some frames lack mounting positions and the shape or material of the seat tube ...


6

Shimano Hollowtech II cranks use two pinch bolts to secure the crank to the axle. From your picture it looks like you have those. You are missing the plastic end cap, and you may possibly be missing a washer that sits between the crank and the frame. There is no spacer, the play is probably because the crank arm is not fully on the spindle. To install the ...


6

Nothing is missing. To adjust these you loosen the pinch bolts on the left crank with a 5mm wrench, use the same 5mm wrench to gently tighten down the large black preload adjusting bolt that's found on the outside of the left crank, and then re-torque the pinch bolts. This bike appears to be in pretty rusty/unkempt shape. It would be a good idea to at ...


6

If your bike was previously set up with three chainrings, then the new single ring should be placed in the middle chainring location (i.e., on the inside of the four mounting points of the crank). Assuming that this is a somewhat ordinary mountain bike, the previous middle chainring was likely a 32t, so the new 34t single ring should fit with sufficient ...


6

Shimano might not say it's okay, but you can use any 130BCD chainrings that you can find with that crankset1. You'll get the best shifting performance if you pick a matched set of chainrings from a single vendor. The one thing to avoid is any chainrings that say Narrow/wide in the description, these are 1x specific and won't work well on a double crankset. ...


6

Nope, it won't hurt anything. It's unlikely, but the worst case is that you might knock the cable crimp (the cap on the end of that cable) off eventually, which could then cause the cable to fray, which would then eventually need to be replaced. I would try to bend the cable so that it is tucked away behind a piece of the bike frame or the front derailleur ...


6

You've broken your bottom bracket's axle. There is no way to safely reattach, so you're up for a replacement bottom bracket. Ideally you'd install a cartridge BB that duplicates what you have. The crank arm (in your hand) is probably okay to reuse, though have a good clean and a close inspection before doing so. Dings are fine, chips maybe, and cracks are ...


6

It might be possible to make a new thread using helicoil. It is a job for a good bike-shop but should be cheaper than a good pair of cranks.


5

regarding the amount of teeth on the sprockets/crankset: The ratio between the amount of teeth on the rear sprocket and crankset determines the gear ratio of the bike. Even though you have a gear hub the ratio between the sprockets will still determine your gear ratio. The smaller the sprocket in the back/the bigger in the front the higher your top speed is,...


5

There's a few factors that can lead to this problem and range from tool and crank material quality to user error. If you have a tool made from a weak metal or is manufactured badly (ie diameter is wrong), the threads on the tool can easily be ripped off. Similarly, if the cranks are made from a weak metal, then the threads on the arm can strip off. User ...


5

The Park tool will work. A 14mm socket and a ratchet will also work. If the crankarm has been loose for some time there is a chance the movement has ruined the crankarm by distorting the square hole. I would attempt to tighten the bolt then see if the arm still wiggles on the crank axle. If there is no movement, ride for a few days then recheck the bolt ...


5

Locktite blue (also known as 243), or other similar thread lock liquids may eliminate the bottom bracket threads coming loose. Another method to stop creaks between the BB and the frame is to use plumbers teflon tape. Just one or two wraps on the BB threads before installation will keep the bottom bracket from backing out and fill voids to eliminate ...


5

I think what is going on here is that you were running a 47.5mm chainline (standard for MTB triples, see here) with the FY301 crank, but the M361 crank gets you a chainline of 50mm. When switching out three-piece cranks you have to pay attention to the chainline and you also have to look at cartridge bottom bracket axle lengths and potentially replace the ...


5

If you just want to go with something basic that's close to what you have, it's easy to get a replacement repair type crankset for this sort of bike. Check your tooth count, but it's probably 42/32/22, and then check the length, which is usually stamped on the inside of the arms. It will probably be either 170mm or 175mm. The other distinguishing factor is ...


5

SunRace spec sheets show the crank bolts should be M8x1.0. The bolt diameter is 8mm and there is 1mm betwween thread peaks. This size is by far the most common. However there are other standards. Truvativ seems to have the most variations using M8, M12, M15 plus some self extracting bolts. If the bolts starts but binds it is likely the right diameter but the ...


5

What you need to do is look up the total capacity specifications of both your front and rear derailleurs. For a front derailleur the total capacity is just the largest difference between the largest and smallest chainring tooth counts the derailleur can handle. The total capacity is for a rear derailleur is the largest (difference between the largest and ...


5

Everything looks right. Whenever using a crank puller but especially when it's taking a lot of force, it's very important to have the tool installed into the crank arm with some real torque, not just finger tight and never loose. You can grease the threads if there's roughness. Here with the nutted spindle it's a good idea to start with the puller either in ...


5

Probably ISIS splined. That’s the only one with splines of that length with the smooth end. https://www.sheldonbrown.com/bbsize.html


5

It looks like you have a crankset with non-removable chainrings. The 'bolts' you are measuring the geometry of are just screws holding the chainguard on. The chainrings appear to be pressed steel and attached at the crank axle. It's much more likely the pressed steel rings are bent than the bottom bracket axle, so replacing the entire crank is possibly all ...


5

gshenk's post is excellent general answer, here's the specific answer for the setup on the Digger Comp. The Digger comes with an RX-600 40t crank, RD-RX812 derailleur and CS-M7000 11-42 cassette. The RD-812 derailleur is compatible with wide-range mountain bike 11 speed cassettes (which have different spacing that 11 speed road cassettes). It's not designed ...


5

There have been front drive designs, but all variations I've seen are either impractical, structurally inferior, or both. There is no real benefit to having both wheels deliver power, and that would add a gigantic amount of weight and likely be quite problematic. Imagine needing two separate drive trains that involve separate chains, cassettes, derailleurs, ...


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