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15

The bottom bracket is not damaged, the left hand crank arm is. You have a 'two piece' crank where the right side crank is permanently attached to a steel axle, and the left hand crank clamps onto the axle with two pinch bolts. The axle has small splines cut into it where the crank clamps on and the crank has corresponding splines cut into it. for the crank ...


9

On the Sora R3000 (and many modern cranksets) the axle, right hand crank arm and chainring spider are all one piece. The left hand crank arm fits on the splines on the axle, and is held in place by two pinch bolts. The thread you see in the hollow axle is for a plastic cap that is finger tightened to provide slight pre-load of the bottom bracket bearings. ...


8

What tools do I need to remove the bracket? There's a plastic cap on the sides of the crank that you can pop off or unscrew, and inside there will be a Hex socket of about 6~8 mm , or a 6 sided nut to remove with a suitable socket. A spanner will not work. Then you need a crank puller to remove the crank arms from each side of the BB axle. This tool ...


7

Ideally you do it with a press type tool, one cup at a time, with stepped bushings that mate snugly with the cups and the BB shell. For the first cup, one of the bushings is interfaced with the frame to act as a pilot so that the cup stays square and goes in straight, and then for the second cup the other bushing is doing the same while contacting the first ...


7

The crankset is a BB30 FSA Gossamer with a 30mm spindle. There are four bottom brackets that will fit this crankset which might be in your bike. Thes are BB30(68/42), BB30a(73/42), PF30(68/46) and PF30a(73/46). To determine which one you need, there are two things to measure. First measure the inner shell diameter. 42mm is BB30/BB30a, while 46mm is PF30/...


7

When I fixed up my old bike it had a typical BB with fixed and adjustable cups. I planned on replacing with a cartridge BB so I didn't want to get the special tools just for a removal operation. Though I did get the special toothed socket needed to install the new BB (a cheap version online since I'll only use it a few times). Using a slot screwdriver, or ...


6

No, it's because the colors are not a universal indicator of what grade/type a particular compound is across brands. Loctite/Henkel products do use their color scheme to communicate strength level, but even there it's more complicated than that because there are different compounds that are the same color and might differ in other attributes like gap ...


6

There's two parts to this - the circular lockring around the outside and the cup. I'm a bad and lazy mechanic and I use a pair of sliding lockjaw adjustable pliers to remove the lockring (assuming its not just hand-tight in the first place). This tends to marr the outer edge of the lockring, but on an old beater bike that's not important. You can use a rag ...


6

Three-hooked spanner is not necessary, but it would improve the engagement and decrease chance of stripping a notch on the BB lockring. Parktool makes the HCW-5 spanner, which combines both a three-hook and a single hook. Here's a relevant quote: One side is a single hook, the other is a hook spanner with 3 notches for better engagement in the ...


5

BSA refers to the diameter and thread pitch of the threaded bottom bracket shell in the frame. Square Taper and ISIS refer to the crank interfaces on the ends of the axle of cartridge bottom brackets (that fit in BSA threader shells). See this Sheldon Brown page for info on cartridge bottom brackets (pictures near the bottom). A quick look at the Cyclone ...


5

You are correct that you may run into clearance problems if you just put on a road crank. You should get a narrow-wide ring no matter what. There's no reason to use anything else for a 1x. To get the kind of gearing you want (44t and higher on a mountain 1x crank), the main way of doing it from scratch is get a 1x crank arm set and BB of the sort ...


5

Bicycle blue book says the 850 came with a BB-Lp26 bottom bracket, which was 68mm wide, 110mm spindle length, square taper. There are some new (old stock) on ebay, but I don't see why a newer BB-UN26 couldn't also be used (or any other standard ISO bottom bracket made for a 68mm wide shell, with a 110mm spindle). I'd measure the BB shell and spindle width, ...


5

Because I feel that I'm stretching a little too forward, causing my back to ache, I've decided I would decrease my stem from 110 to 90. You can help this by also moving your saddle forward. If you combine that with raising your handlebars some by changing the stem angle, you'll shift your torso to be more upright, too. That will also shift your weight ...


5

I'd reuse that spindle. The tips bear the smallest load. A nick near the center of the spindle would be more significant


5

The percentage of the total area of the tapers that is damaged is very small, so you should be able to re-use the bottom bracket. However, cartridge bottom brackets are quite cheap, so if the bearings are showing wear I'd just replace it. IF you do re-use it, you'll need to carefully file down any burrs raised by the angle grinder, those will prevent a new ...


5

With respect to replacing the bottom bracket with a cartridge unit: You almost certainly have a square taper axle an corresponding square holes on the crank. I don't think the loose ball bearing types were ever made with Octalink, ISIS or any other axle type. Square taper cartridge bottom brackets come in a variety of axle lengths that work with different ...


5

Possibly yes it could be the bottom bracket making periodic noises. Can also be pedals, chain sticky links, bent chainring, damaged teeth on chainring, alignment of front mech. Crack in frame, damaged seat, damaged seatpost clamp, or damaged saddle rails clamp. One elimination technique is to figure out if the noise is timed with crank rotations, or with ...


4

Does whether the bike folds have anything at all to do with this compatibility between BB and crank? Executive summary: NO! Longer answer: Here's the Sheldon Brown link: https://www.sheldonbrown.com/bbtaper.html Even though both ISO and JIS have the same taper angle, ISO spindles are narrower than JIS spindles, so an ISO crank won't go all the way onto ...


4

I'm going to offer the contrary answer - why not fix it properly? Summary: Your spindle/crank interface is damaged, so the crank has been forced onto the spindle and is now at a high state of torque. Its confirmed that the spindle is damaged and likely that the crank arm is now damaged as a result. And the rest of the bike is OK. So the worst case is ...


4

The spindle length depends on crank and chainline (distance from center of top tube to chainrings). In road bikes the chainline is almost always around 43 mm (exception being boost spacing), so the safest bet is to pick the same spindle length as on the bike where the cranks came from. Different cranks may have different chainline on the same spindle. If ...


4

Old-fashioned cup and cone type bottom brackets have one adjustable cup, with a lockring. The adjustable cup lets you set the bearing tightness, too loose and there is play, too tight and the spindle won’t turn. With a cartridge B.B., the bearings are self-contained and the cups are installed to a given torque which is normally pretty high as bike parts ...


4

Here are some examples of tools made for that kind of cup, which doesn't really have a universally understood name or type that I've ever heard of. The Hozan one pictured has a guide/holder bit that wouldn't be used with a cottered spindle like the one you have.


4

That's a Shimano Hollowtech II crankset and bottom bracket. Your bottom bracket isn't causing that problem - that's something seriously wrong with your crankset. The only thing I can conceive of causing that problem is the two pinch bolts on the non-drive side are loose. (your first photograph - the side without the chainrings) There are two bolts that ...


4

Maybe there is a problem with the bottom bracket, maybe you re-assembled something incorrectly, maybe there is something else loose that is rattling. Check the bike for rattles and loose components by holding it by 10-15cm above the ground and dropping in onto its tires. Check the bottom bracket is re-assembled correctly. Turn the cranks by hand. They ...


4

You have a sealed cartridge type bottom bracket. You can take it out but you can't disassemble it, clean or service the bearings. If the bearings are running smoothly without excessive resistance leave it alone. If you do need to replace it new units are not particularly expensive. The cranks fit on square taper or spined interfaces on the axle. The bolt in ...


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 ...


3

The bolt in the cranks means you have a 3-piece crank (separate left and right crank arms and cartridge bottom bracket, with a square taper or splined axle-crank interface). No power meters come in this type of crank because it's old technology that only appears on inexpensive bikes these days. However 3-piece cranks use a threaded bottom bracket shell, ...


3

No. It seems that you have already done your homework and know why you don't want to fix things properly or why WD-40 doesn't really work. But you had to ask, didn't you.


3

A 2018 bike with have an R3000 Sora 9 speed groupset. The problem here is that you have a 9 speed chain that probably won't shift well on an 11 speed crank. As 10 and 11 (and now 12) speed systems were created, the cassette sprockets needed to be more closely spaced, which required the outside width of chains to be decreased. The distance between crank ...


3

The trek archive is a bit light on B.B. detail but mentions an FSA Vero crankset. Googling FSA Vero shows me images of a square taper which is pretty straightforward and means that the bottom bracket is going to be threaded. Most likely it is 68mm across the B.B. shell, which you should measure. If it’s 68mm and you’re getting Shimano 105 cranks, just ...


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