How To Fix Your Squeaky Bicycle Bracket
How to fix a creaky frame can be something we ask ourselves quite often as cyclists. Often we look towards changing bearings and adding excess amounts of grease to areas that may not even need it. Sometimes the problem can run even deeper. This is why facing, reaming and tapping frames is essential. This ensures that components interface correctly with the frame. Tech editor Michelle went to Velo Atelier to find out more.
Transcript
00:00 (upbeat music)
00:02 Creaky bottom brackets and rubbing disc brakes
00:07 are two extremely common complaints
00:10 among cycling enthusiasts and pros alike.
00:13 Very often, we look at the components instead of the frame
00:17 when we're looking for a solution,
00:19 and that might well be an error.
00:20 Bottom brackets, disc brake mounts
00:22 were designed to be seated in frames that are up to the job,
00:25 and unfortunately, that isn't always the case
00:28 straight from the factory,
00:30 and that's where facing comes in.
00:32 This is the process of removing excess material
00:34 to ensure that holes that are meant to be round
00:36 are in fact round,
00:37 and surfaces that are meant to be flat are flat.
00:40 We're here at Velo Atelier up in Warwick
00:43 to face this frame and see what a difference
00:45 that extra step of TLC can make.
00:48 (upbeat music)
00:50 Co-owner at Velo Atelier, Lee Prescott,
00:56 has been designing and manufacturing frames for 37 years.
01:00 He designs and manufactures
01:01 his own Meteorworks metal frames,
01:03 as well as working with partners,
01:05 creating carbon frames such as Fesca and Open,
01:08 and also servicing frames from a great many brands
01:12 using lots of different frame materials.
01:14 Now, he tells me that he never builds a frame up
01:17 without first checking the tolerances
01:18 and then facing, reaming, and tapping if it needs it.
01:22 Now, tell me why that is.
01:24 - We wouldn't even dream of not facing
01:27 and reaming and tapping all the interfaces on the frame,
01:31 'cause it simply makes the build easier and more efficient,
01:35 and it means that all the parts will last longer
01:37 and just work more efficiently.
01:39 - Okay, so you've got a brand new frame that's just come in,
01:41 or it's a frame that's come in
01:42 for a really high-level service,
01:44 and you've stripped it all off,
01:45 and you're gonna check each of the elements of the frame
01:48 to prep it before building it.
01:49 Just run me through what exactly you're gonna be doing
01:51 with each area of the frame.
01:53 - So, starting with the disc brake bosses
01:56 on the frame and the fork,
01:58 what we're doing there is making sure
02:00 that they are both parallel to each other
02:02 and also creating a face that is perpendicular
02:06 to the disc rotor so that the pads hit it squarely.
02:11 Then, with the bottom bracket,
02:13 what we're doing is ensuring, if it's threaded,
02:16 that all the threads are free and clear and round
02:20 so that the threaded bottom bracket
02:21 will go in nice and easily without damaging any threads.
02:25 But most importantly, we're making sure
02:27 that the faces on each side are both parallel to each other
02:31 and straight and flat so that any cup
02:34 that's biting into it is pushing in level
02:37 and maintaining a level of parallelism.
02:39 With the headset, we're facing the surface
02:43 that the bearing is gonna mate to.
02:45 So, whether that's an external headset,
02:47 a zero-stack headset, or an internal headset,
02:50 we're braiding those faces
02:52 so that they are parallel to each other
02:54 and ensuring that they're round as well.
02:57 That way, the bearings sit in alignment
03:00 and prevent any excess wearing of the bearing.
03:03 - Facing, reaming, and tapping are generally associated
03:12 with metal frames and less so carbon frames
03:15 which are made in a mold and, in theory,
03:18 should be up to spec and shouldn't really need it.
03:22 Why might you need to face, ream, or tap a carbon frame?
03:25 And is it something we should perhaps see more of?
03:28 - So, you're right.
03:29 It's much more prevalent on metal frames
03:32 'cause on a metal frame, you have to overcome
03:34 any warping or distortion that's happened
03:37 during the welding process.
03:39 On a carbon frame, as you say,
03:41 they come out of very expensive molds
03:43 that are built to very high tolerances.
03:45 So, most of the time,
03:47 providing all has gone well with the build,
03:49 the layup is in the right place,
03:50 the shrinkage has happened at the appropriate rate,
03:53 the humidity that were built,
03:55 all these factors that need to be controlled
03:57 and are controlled in good quality factories
04:00 should mean that the frame comes out
04:02 in a pretty good state
04:04 and then any final fine finishing can be done at the factory
04:07 just to polish up areas that need a higher tolerance.
04:11 So, it's less required, typically, on carbon frames,
04:15 but where the issue arises is when you get certain designs
04:20 that have separate cups and then if you're fitting,
04:23 for instance, at the bottom bracket end,
04:26 bottom brackets are two separate cups that aren't joined
04:29 and the faces are not parallel, for instance.
04:32 When you press them in, they can then deform slightly
04:35 and that's when you get bearings
04:37 that are not concentric and parallel.
04:40 And that's what leads to excess wear
04:43 and the dreaded squeaking and creaking.
04:45 - And one way to deal with that might be facing it
04:48 in terms of the bottom bracket.
04:49 There are probably more cost-effective options available,
04:52 right?
04:53 - Yeah, absolutely.
04:54 Unless it's wildly out, in which case,
04:58 it's a manufacturing defect
04:59 and should be under warranty anyway.
05:01 You can normally get around a lot of these problems
05:03 by the use of a good quality bottom bracket
05:05 that's connected in some way.
05:07 So, something like this that screws together
05:10 with a very fine thread,
05:12 that maintains the concentricity
05:14 and parallelism of the bearings.
05:16 So, that reduces any issues
05:17 you're gonna get with misalignment.
05:19 - Whereas at the back end with the bosses,
05:22 that is something that often you might get
05:24 just that little bit of paint or something.
05:26 It can really could be beneficial with a carbon frame.
05:29 It's not quite so expensive.
05:30 - No, well, the tooling exists
05:32 for facing carbon disc brake mounts.
05:36 So, actually facing a carbon frame in that area
05:39 is no more time-consuming or expensive
05:42 than doing a metal frame.
05:44 And it's something that most frames could benefit from,
05:47 even if it's just to remove excess paint
05:49 that's slightly misaligning the caliper.
05:51 And the key thing is just creating
05:54 a perpendicular surface to the disc,
05:57 so that when you're clamping that brake caliper to it,
06:00 it's parallel.
06:01 So, at least your pads are hitting the rotor squarely.
06:05 (upbeat music)
06:08 - So, if you've had a bike that's come into your workshop,
06:12 it's perhaps not had the best QC,
06:14 it's not maybe the best frame,
06:16 and the components haven't been running in it very smoothly,
06:19 what are the very common symptoms
06:20 that you would see as a result?
06:22 - So, I guess starting from the rear and moving forwards,
06:25 obviously disc brake bosses
06:27 that are not parallel and perpendicular to the disc,
06:31 you get the rubbing that we all have heard
06:33 from time to time.
06:35 It's maybe slightly spongy action on the brake,
06:38 regardless of how well bled it is.
06:40 Disc pad wear being very uneven is a real common symptom.
06:46 And then coming forward to bottom brackets,
06:48 creaks that can't be defined.
06:52 When you remove the crank arm,
06:54 in the worst case scenarios,
06:56 misaligned bearing will destroy the crank axle.
06:59 So, things to look for are,
07:01 when you remove the crank arm,
07:03 check in the axle to see if there are small scores
07:06 or uneven wear patterns.
07:08 Now, really, your crank arm axle
07:12 shouldn't be sliding inside the bearing.
07:15 The bearing should be rotating.
07:17 If the bearings are misaligned,
07:20 then it prevents free rotation,
07:23 which means you'll start to get more sliding,
07:25 which as soon as metal slides over metal,
07:27 you're gonna start wearing it away.
07:29 So, if you've got a very expensive power crank,
07:33 that's an expensive mistake.
07:35 And then for headsets,
07:37 if the bearings in headsets are misaligned,
07:40 you'll either feel kind of tight spots,
07:42 so your steering won't be free and even.
07:45 That can obviously lead onto the actual bearings
07:50 pitting the races,
07:51 and then you get kind of indexed steering.
07:54 And there's no need for it.
07:55 You know, a nice flat parallel bearing surface
07:58 means that your headset should last
08:01 for as long as you wanna keep it.
08:02 You know, I have a Chris King headset
08:04 that's over 20 years old,
08:06 and it's swapped from a bike to bike,
08:08 and it's still running as good now
08:09 as almost the day I bought it, so.
08:11 - You mentioned to me earlier
08:13 while we were preparing the last frame
08:15 that it might be a process that people do
08:17 if they're gonna hold onto a bike for much longer.
08:20 Is it fair to say that it would take some time
08:22 to notice that a bike actually
08:24 was presenting with these problems?
08:26 - Yeah, potentially.
08:27 I mean, you know, most brand new bikes
08:28 with brand new components are gonna work,
08:31 and work fairly well,
08:33 and not creep straight off the production line.
08:35 So for a bottom bracket, for instance,
08:37 wearing of the bearings due to misalignment
08:40 is going to take a little time.
08:42 I would say, you know, if you're really unlucky,
08:45 and you've got a slightly non-concentric bottom bracket
08:49 with separate cups that were misaligned
08:53 when they were pressed in,
08:55 I mean, you'll feel it straight away
08:56 because the crank won't want to move freely.
09:00 It might have tight spots in its rotation.
09:03 And if that's the case,
09:05 you're gonna wear the bearings out really quickly,
09:07 within months.
09:09 Most problems are not that bad.
09:10 You know, that's worst case scenario.
09:13 And if you ever come across that,
09:15 actually that's a manufacturing issue,
09:18 and a warranty issue.
09:20 So, you know, you shouldn't be coming to people like us
09:22 to pay to get it sorted.
09:24 You should be speaking to the manufacturer,
09:27 and having that problem resolved.
09:28 (upbeat music)
09:31 - We've talked a lot about,
09:36 well, we have talked,
09:37 and we will talk a lot about tolerance.
09:39 It will be good just to define that,
09:41 and also to understand,
09:42 I mean, our videographer earlier,
09:44 I'm sure you won't mind me mentioning,
09:45 was asking what he was looking for
09:47 when he was filming the bosses.
09:49 And the kind of numbers that we're talking about
09:52 are not viewable to the eye, right?
09:54 - Not really, no.
09:55 No, I mean, we're talking about fractions of a millimetre.
09:58 Tolerance essentially refers to
10:00 the amount above and below the optimum size
10:04 something can be,
10:05 and it still work properly.
10:06 Certain areas don't really require a high tolerance,
10:10 or a very small tolerance, should I say.
10:13 Other areas do need to be toleranced much more accurately
10:17 to work correctly.
10:19 So, such as an interference fit
10:21 with a hard cup,
10:23 or properly aligned bearings.
10:26 - And I mean, tolerance is something
10:28 that the manufacturer would look at
10:30 as part of their quality control, or QC process.
10:33 But there are actually two sides to that,
10:35 the other being consistency.
10:37 - Yeah. - Yeah.
10:38 - With anything, the higher tolerance you want something,
10:40 the more laborious that process becomes,
10:43 and hence, the more expensive.
10:44 Also, checking it,
10:46 the finer the tolerance,
10:48 accurately measuring that becomes more difficult,
10:50 and hence, costs more as well.
10:53 With most manufacturing processes,
10:55 the two things are, to what tolerance,
10:58 and also a level of consistency.
11:01 Because you always want, as much as possible,
11:04 to have them all the same at the defined tolerance.
11:07 - So initially, I actually wrote a feature about this
11:09 before I came to speak to you.
11:10 And I spoke to several bike shops in that process,
11:13 it was probably about six.
11:15 And it was almost a 50/50 split
11:18 between those that said,
11:20 yes, frames out of tolerance that need facing
11:22 is a huge problem, we have to do it all the time,
11:25 and those that said,
11:26 I don't know what you're talking about,
11:27 this isn't a problem at all.
11:29 I mean, the cynic could suggest that
11:31 it could just be down to their attention to detail.
11:34 It could also be down to the brands that they're stocking.
11:37 What other reasons might you give,
11:39 or are those the only available reasons?
11:41 - I think both of those reasons are potentially valid.
11:44 I also think, you know, it's something that these days,
11:48 with mass-produced carbon frames, it's not so prevalent.
11:51 So there's a lot of shops that may not have the experience
11:54 to be able to offer that,
11:56 or just may not want to invest in the appropriate tooling
12:00 to do metal work in-house.
12:04 Everything that we've accumulated through the years,
12:06 if you went to buy it all today,
12:08 would probably cost you in the region of six to eight grand.
12:13 - And we've talked an awful lot about tolerances.
12:17 There's also an element of consistency in there as well.
12:20 And all of that comes under quality control, or QC.
12:25 Now explain to me what happens,
12:27 you've worked as a consultant for brands,
12:29 what happens in a factory,
12:31 and why is it that some of them
12:33 might have more stringent QC than others?
12:37 - It's all about having a defined level of consistency
12:40 and having bikes built within a certain tolerance.
12:45 So the more consistent and the higher,
12:48 or tighter the tolerance that you want,
12:51 the more you're gonna pay,
12:52 because that requires more checks, more consistent checking.
12:57 And how that is done within each independent factory,
13:02 again, depends on the price.
13:04 So how you want it reported,
13:06 how you want the testing done,
13:09 how you want the calibration of the equipment done.
13:11 The more stringent you want to be,
13:13 the higher that cost is going to be.
13:15 So if you're trying to put out a £1,000 complete
13:20 carbon road frame, or road bike even,
13:23 you're not gonna be able to physically afford
13:26 to have the highest levels of quality control.
13:29 It would make it not a commercially viable option.
13:31 And it means that all those people
13:34 that have now got £1,000 road bikes
13:36 that are exploring the sport and getting into things
13:39 wouldn't have had that opportunity.
13:40 So there's a place for all levels of quality control.
13:44 You shouldn't always just be right at the very highest,
13:47 because none of us would afford to buy a bike.
13:50 - I mean, there must be a,
13:51 how much is a reasonable amount of quality control
13:54 actually adding to the cost of a bike?
13:57 Is it possible to put a number on that?
13:59 - It could be anything up to 10 to 15%
14:04 of the price of a bike is going towards
14:09 quality control procedures at the higher level.
14:11 But yeah, I mean, I think you have to look at it
14:13 as a proportion, which is probably the way
14:16 you would normally work out how much you can afford to spend
14:19 on your QC process.
14:21 - And we can talk about what happens in the factory
14:23 until the cows come home, but it might not help
14:25 a rider at home that's got a bike
14:28 that's creaking or not running smoothly.
14:30 If someone is watching this video and they think,
14:33 actually, I think my bike isn't quite right,
14:36 what should they do?
14:37 - So I think the key thing really is,
14:40 you just need to go, if you don't already,
14:42 find yourself a good, experienced local mechanic
14:46 and chat to them about the issue
14:48 and see what they can do for you.
14:50 There's lots of good, experienced mechanics out there.
14:54 So you just find one that's gonna help you out.
14:56 - So there you have it.
14:59 Hopefully you're riding along in blissful silence,
15:02 and if so, good for you.
15:04 If not, then know that it might well be worth
15:06 having your frame tolerances checked.
15:08 And the good news is that fixing the problem
15:10 might not be as expensive as you think.
15:13 So I hope you enjoyed this video.
15:14 If you did, then do hit the like button.
15:17 Let us know what you thought in the comments
15:19 and subscribe if you'd like to see more of our videos.
15:21 [MUSIC PLAYING]