17

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

Judging from your videos, it appears that the chainrings and crank are no longer connected. It appears that you have something called a one-piece crankset. If you are confident that you can learn how to disassemble it, I’d say you’re up for the repair. Once you have the crank off the bike, you’ll be able to see how the chainrings and crank arm are connected. ...


9

Carbon is the dominant frame material in performance bicycles. You can't thread carbon. There are two ways to get bottom bracket cups into a carbon frame: bond (industrial-strength glue) an alloy sleeve into the shell, or use a press-fit system. You are potentially adding several manufacturing steps by adding a threaded sleeve to a carbon frame, and the ...


9

Threadless cartridge BBs have their place, and that place is where the threads are destroyed. Thankfully you're not there yet. They are a compromise because they tend to have creak issues sooner or later no matter what. You should take the frame to a shop with a proper piloted BB tap set. One side of your shell looks fine. The fix is to install the pilot ...


8

Some mechanic might have put a liberal amount of grease in the BB shell and also in the head-tube prior to assembly. Then copiously greased the seat-post as well. Grease has a tendency to migrate, especially in hot weather and move to the strangest places, the bike may have been stored upside down, head or tail-up. Think of it as a gift from whoever put it ...


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

Looks like what is known as an 'adjustable cup and cone' bottom bracket. That means the bracket can be disassembled, and the axle and ball bearings will come out; also the clearance between the cups and cones (the surfaces the ball bearings run on) can be adjusted. This differs from a 'cartridge' unit that is pressed together and cannot be disassembled or ...


7

You're going to need to replace the entire BB. The drive side cup is reverse threaded. (This isn't true of older bikes of certain nationality, but the nylon cable guide suggests yours is new enough for this not to be a concern.) To answer your questions: The squareness of the cups is very important for the BB to function. To get the cup out without ...


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

While we don't have your bike in hand, or at least a video of the issue, it sounds more like your freewheel or your freehub has failed. I suspect that new cyclists might say the gears have failed. Edit: This answer actually mis-diagnosed the problem (albeit I'd argue for good reason - it was given before videos were provided!). I'm leaving it up for general ...


6

The sleeve provides a tiny amount of extra protection for the bearings and is not structural in this instance. They are often fiddly to fit on these "boutique" bottom brackets and even people who deal with them frequently can cock up the tube alignment from time to time. You may be able to break it up with a screwdriver, if it's brittle enough, to ...


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

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

In light of some recent questions, I'm going to focus this answer solely on bottom brackets. The OP’s frame has a British threaded bottom bracket(aka BSA standard). These were by far the most common standard on most bikes in the 2000s. Some frames, mainly Italian ones, used the similar Italian threaded standard. The BSA shell is 35mm in diameter. The Italian ...


5

Yes, you should be able to run the current range of groupsets. All the mount points are the same as 20 years ago, except for 11/12 speed freehub body, so you might need to change the rear hub or wheel. Your BB shell is a regular threaded 68mm, should be absolutely no trouble to find suitable BB cups.


5

Nathan's answer covers it all, but to expand on the last point... That cup is dead. Your last resort is to cut the cup out - I've done it once. In my case the bearings had failed, and the rider was rubbing the BB axle on the cup directly, slowly eroding through the casting. The cup would not turn even using the correct BB cup wrench a park HCW-4 You ...


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

Once you get the bearing and cup off the spindle, you can assess the state of the bearings a little. Turn them with your fingers while pushing hard in both the radial and lateral directions. This kind of test isn't perfect because the loads applied in use are so much higher, but sometimes it can reveal notchiness or roughness that lets you know you'd be ...


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

This looks like a standard British bottom bracket with a fixed cup and adjustable cup. This article gives a good overview of how to service. It looks like your lockring is missing. Also, it doesn't look like you'll be able to use a pin spanner on the adjustable cup. Not clear from the photo what kind of wrenching affordance the cup has, but it should have ...


5

Park Tool Repair says greasing the spindle is 'an option', but says it is to prevent corrosion, rather than having any effect on how the crank goes on the spindle. Slathering grease on is seems like a waste as most is going to get pushed out of the joint.


4

Your question is a little ambiguous but I think you are proposing to replace the Apex non-drive side crank arm with a Shimano 105 arm with a 4iii power meter built in. That will not work, the SRAM and Shimano cranks use a completely different attachment method. 4iii do not seem to offer power meters pre-installed in a new SRAM crank arm, but they do seem to ...


4

There is an item Shimano calls a crank Plate Pin, which is that black plastic plate visible on your crank, and circled in the diagram below (4). It has a little pin which should stop the crank coming off in this situation, yours must have been damaged if the crank came off and it should be replaced. Many internet commenters scorn them but has worked for me ...


4

I think this is fine, especially if you are using the outer sprockets most of the time.


4

If it is an M30 Thru BSA, then the cups will say 'M30 THRU'. As they say M30 and only M30 then they are the M30 BSA version. The latter suits crank spindles which are 30mm drive side, 28mm non-drive side, as the Zayante crank is. If they say anything else (like press fit) then (future readers) can match that to other models on the Praxis website before ...


4

It's set by the crank, and is like this because GRX is targeted at 135mm/142mm rear ends. GRX takes the same BB as any HT2 road crank. It's enough to matter, but chainstay length is the other piece of how much it matters. Doing this kind of thing on super short chainstay bikes can yield pretty compromised results in terms of number of rough combinations, ...


4

You cannot fit a threaded bottom bracket into a press-fit shell frame. A threaded Hollowtech II BB for road cranks will only fit in ISO threaded bottom bracket shell of width 68mm. GXP is a crank axle standard not a BB standard, so that does not tell us what the press fit cups in the shell are. What you need to do is measure the cup diameter and shell with. ...


4

Of course, but be aware that there are patents (for the design) and trademarks (for the name Hollotech 2) applicable and the compatibity might be in two separate aspects. The first aspect is the compatibility of the cranks and the bottom bracket. Here it is enough that the crank spindle of the correct 24 mm diameter and the right length. FSA Megaexo 24mm ...


4

Money. Threading holes is a process that has to happen during manufacturing. Both sides have to be concentric and parallel, and the taps used to make the threads have to be pretty good, so they wear fast. By comparison, the bottom bracket holes on a carbon fibre frame can be made in the layup process, and (in theory) should come out the right size ...


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