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10

You need one of four things: An eccentric bottom bracket. Like these An eccentric hub. Like these Horizontal dropouts. Like these A chain tensioner. There are a number of different types. You only need one of the four, but these are the only ways to get the chain tension correct on a single speed. (I should say "almost only." Blind luck works every so ...


9

Your crank arm is trashed. With the crank bolt removed, gently ride around a few miles, it should work itself loose enough that you can yank it off. Otherwise many shops have basically a slightly larger crank puller for addressing this issue, where they chase out a larger set of threads, then use the larger puller to get it off. The crank arm typically ...


9

Like you said, they are cottered, what makes them aligned is that pin through a hole, which at the same time tightens the crank arm around the axle. If you google "cottered crank", you can see the spindle, which has a slot in each side. My hypothesis would be: or the cottering bold got deformed, or the spindle slot itself got deformed, or both. A bolder ...


8

External bottom brackets allow you to have both large bearings and a large, hollow bottom bracket spindle. A large hollow spindle can be designed to be as stiff as a small solid spindle for less weight. Smaller bearings reduce the longevity of a bottom bracket, so the typical bottom bracket design allows a narrow range of suitable spindle sizes and bearing ...


8

You're right, you want to space it between the shell and cup. You can put spacers on either side to get the chainline right. Most cranksets come with spacers (2.5 mm is probably the most useful size for you) but if yours didn't any LBS should have a few to sell you. Something like this: http://wheelsmfg.com/bottom-bracket-spacer.html (I don't know if ...


8

Possible causes: There is "play" in the bottom bracket bearings, this could also explain the clicks. Usually this is quite noticeable, and you can check it by grabbing the crank-arm and trying to move it sideways. Usually this is not the cause for variable chain tension on singles; The chainring is "eccentric", either because of haveing been tightened ...


7

There are many possible causes of creaking. But Deemar has the most likely reason in this case - the cranks are loose on the axle. Think about how a creak is produced. It's one item sliding over another. But instead of sliding it's repeatedly sticking then jumping. The amount of movement might only be a fraction of a millimetre. The OP would have noticed if ...


7

This is a very subjective opinion. A standard like "change your oil every 3000 miles" doesn't exist as far as I know, although here is a suggested one. I ride about 3,000-4,000 miles a year and my rule of thumb is to do the hubs every 300 - 500 miles or so, and the bottom bracket twice a year. Works out to a hub overhaul about every other month. Both of ...


7

If it's only 2 months old, they have to replace the broken part in guarantee for free. Isn't it? Anyways I checked the specs, this bike has Truvativ Firex GXP crankset. It has integrated bearing, so it should not move side to side. The clicking noise usually means loose or damaged bottom bracket. First I would try to reinstall the crankset with correct ...


7

You probably didn't remove material when you cross-threaded the bottom bracket shell in. If it's a steel frame, you can cut new (correct) threads with the correct taps. The taps are quite expensive, (they have to line up, and one is upside down, find a shop or local framebuilder who has one. Baring that you should chase the threads : grab old steel bb ...


7

It's hard to tell from your picture because they're out of focus, but they look a bit like grease nipples: i.e. like the ones in the top left of the picture. Do they have the little ball bearing in the middle?


6

Looking at the spec of your bike it says the BB is a cartridge unit. This probably isn't serviceable -- it's designed to be replaced when worn out, so just keep riding it until it grinds or gets excessively sloppy. The hubs might be serviceable. If you ride a lot in nasty conditions, or you're aggressive with the degreaser you might want to service them. ...


6

if you are positive it's coming form the bottom bracket, and you have already R&R'd them, try using Teflon tape instead (plumber’s tape), wrap it around the cups and reinstall them - this should fix any squeaks in the BB.


6

There are several possible causes of noises you can get from your bottom bracket. Bad bottom-bracket bearings Bad pedal bearings Loose crank arms Loose bottom-bracket cartridge Loose chainrings Of these the loose crank arm (which may be silent or may be accompanied by a creak on each stroke) is probably the one needing the most immediate attention, since ...


6

From Trek's archives and Bikepedia, it looks like that bike has an FSA Vero compact crankset (no mention of the bottom bracket (BB)). From the Amazon page for the FSA Vero Compact it appears the crank is compatible with a JIS square taper bottom bracket. JIS square taper bottom bracket is a common type of cotterless bottom bracket, available from many ...


6

It's a bottom bracket cup. There are specialty tools you can use to remove it such as the HCW-11 on this page, or if it isn't rusted in, you can probably accomplish the same with an adjustable crescent wrench. Under there are some ball bearings, so make sure you don't lose any when you open it up. The bearings should be in a cage, which would stop you from ...


5

Are you sure the creak is coming from your cranks? It could be the rear hub, it could be the pedals themselves, it could be some combination of things which when you put your weight on them causes a creak. Are you putting extra weight on the bars when you get the creak. I've had creaks from: the seatpost, the headset, the rear hub, the front hub, the ...


5

I've had some problems with the nuts that hold the chainring onto the crank coming loose, so I'm wondering whether that's the source of the noise. It is very likely. It often requires a special tool to tighten firmly, but tightening it will either eliminate a "creak candidate" ... or the noise itself :)


5

It sounds like the cranks are loose on the spindle - hence the creak every pedal stroke / 180 degrees. If the cranks have been loose for a while, then the action of riding the bike will have usually rounded either the square taper on the spindle, or the hole on the cranks. If this has happened, then you will never be able to tighten that set of cranks up ...


5

Pull your cranks laterally. Do they move? Give your cranks a good spin, preferably without the chain. Hear any unusual grinding noise or little clicks ? If you answered no to both questions, keep pedalling. You're still fine. It would be nice if the BB was always smooth as butter, but a little rough doesn't mean it's broken.


5

If you are talking about the things that look like thin, wide plastic washers that go on the outer part of both sides of the bottom bracket, they are called bearing seals. Assuming that you are saying that the bearing seals were not installed, then I would absolutely remove the cranks and install them. They are designed to keep most of the road gunk out of ...


5

The external bottom bracket uses the same thread size and shell width as an older internal BB. They were specifically designed to allow use in a standardized frame without redesign. They do require a new crank set, and depending on the model, and what is on your current bike, that may mean the purchase of extra components in order to be compatible with the ...


5

I think it's impossible for it to be coming from the bottom bracket while the pedals are not turning. More likely it's coming from the rear hub. I'd first check whether the spoke guard (if you have one) has come loose and is rubbing against the cluster. And inspect the area behind the cluster for any piece of trash that has gotten in there. Failing that, ...


5

Take the shell off of each side of that bottom bracket and grease each one up, along with the spindle. When you tighten that bottom bracket back on, don't over torque it or under torque it, if you over torque or under torque that bad boy is going to squeak. If you aren't sure of the torque or you don't have a torque wrench, visit your local shop. Take the ...


5

Sram apex is a double chainring crankset which uses a GXP (aka Giga-X-Pipe) bottom bracket which is an external bearing bottom bracket. I think External Bearing or Outboard bottom bracket are both commonly accepted terms, however there are several different incompatible types of external bottom brackets such as hollowtech, GXP, and Ultra Tourque.


5

By "non-drive" I assume you mean the left side. This is more apt to come loose than the right because of "precession" -- most crank bolts are right-hand thread on both sides, but the motion of the crank arm relative to the shaft tends to loosen the bolt on the left side, whereas it tends to tighten the bolt on the right side. But if this is occurring it's ...


5

This type of bearing is not serviceable. The plastic piece is the seal that retains the grease and keeps water and dirt out. The crank needs to be pressed out to remove the bearings. Try to tap the crank with a soft faced hammer. the bearing on the opposite side should be pushed out by the crank. Installing the new bearings will require some care. I have had ...


5

As this is an older octalink crankset/BB you will require a: Crank Extractor like this to remove the cranks. Bottom Bracket tool like this to remove the bottom bracket. Dust cap removal tool (if it has these) like this 8 or 10mm hex wrench for crank bolts. This is likely to require a lot of effort to free up after 12 years so I'd recommend a repair ...


5

in my experience. BB height affects stability of your ride, but mostly while standing on the pedals since you weight is then directly on the BB. but raising it 7mm may or may not make a difference in your ride. however, raising it ABOVE the axle height will make a dramatic difference in stability. BMX bikes are incredibly nimble (aka unstable) due to them ...



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