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.
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00:00Creaky bottom brackets and rubbing disc brakes are two extremely common complaints among cycling
00:11enthusiasts and pros alike. Very often we look at the components instead of the frame when we're
00:17looking for a solution and that might well be an error. Bottom brackets disc brake mounts were
00:22designed to be seated in frames that are up to the job and unfortunately that isn't always the
00:28case straight from the factory and that's where facing comes in. This is the process of removing
00:33excess material to ensure that holes that are meant to be round are in fact round and surfaces
00:38that are meant to be flat are flat. We're here at Velo Atelier up in Warwick to face this frame and
00:44see what a difference that extra step of TLC can make. Co-owner at Velo Atelier, Lee Prescott has been
00:57designing and manufacturing frames for 37 years. He designs and manufactures own Meteor Works metal
01:03frames as well as working with partners creating carbon frames such as Fesca and Open and also
01:09servicing frames from a great many brands using lots of different frame materials. Now he tells
01:15me that he never builds a frame up without first checking the tolerances and then facing, reaming
01:20and tapping if it needs it. Now tell me why that is. We wouldn't even dream of not facing and reaming
01:28and tapping all the interfaces on the frame because it simply makes the build easier and more efficient
01:34and it means that all the parts will last longer and just work more efficiently. Okay so you've got a
01:40brand new frame that's just come in or it's a frame that's come in for a really high level service and
01:44you've stripped it all off and you're going to check each of the elements of the frame to prep it before
01:49building it. Just run me through what exactly you're going to be doing with each area of the frame.
01:53So starting with the disc brake bosses on the frame and the fork what we're doing there is making sure
02:00that they are both parallel to each other and also creating a face that is perpendicular to the disc rotor
02:08so that the pads hit it squarely. Then with the bottom bracket what we're doing is ensuring if it's
02:15threaded that all the threads are free and clear and round so that the threaded bottom bracket will
02:22go in nice and easily without damaging any threads but most importantly we're making sure that the
02:28faces on each side are both parallel to each other and straight and flat so that any cup that's biting
02:35into it is pushing in level and maintaining a level of parallelism. With the headset we're facing the surface
02:43that the bearing is going to mate to so whether that's an external headset a zero stack headset or an
02:48internal headset we're braiding those faces so that they are parallel to each other and ensuring that
02:55they're round as well that way the bearings sit in alignment and prevent any excess wearing of the bearing.
03:03Facing reaming and tapping are generally associated with metal frames and less so carbon frames which
03:16are made in a mould and in theory should be up to spec and shouldn't really need it. Why might you need to
03:23face ream or tap a carbon frame and is it something we should perhaps see more of? So you're right it's
03:29it's much more prevalent on metal frames because on a metal frame you have to overcome any warping
03:36or distortion that's happened during the welding process. On a carbon frame as you say you know
03:41they come out of very expensive moulds that are built to very high tolerances so most of the time
03:47providing all has gone well with the build the layup is in the right place the shrinkage has happened
03:51at the appropriate rate the humidity that were built you know all these factors that need to be
03:56controlled and are controlled in good quality factories should mean that the frame comes out
04:02in a in a pretty good state and then any final fine finishing can be done at the factory just to
04:08polish up areas that need a higher tolerance. So it's it's less required typically on carbon frames but
04:15where the issue arises is when you get certain designs that have separate cups and then if you're fitting
04:23for instance at the bottom bracket end bottom brackets are two separate cups that aren't joined
04:29and the faces are not parallel for instance when you press them in they can then deform slightly and
04:36that's when you get bearings that are not concentric and parallel and that's what leads to excess wear
04:43and the dreaded squeaking and creaking. And one way to deal with that might be facing it
04:48in terms of the bottom bracket there are probably more cost effective options available right?
04:53Yeah absolutely unless it's wildly out in which case it's a manufacturing defect and should be under
05:00warranty anyway you can normally get around a lot of these problems by the use of a good quality bottom
05:05bracket that's connected in some way so you know something like this that screws together with a very
05:10fine thread that maintains the concentricity and parallelism of the bearings so that reduces any issues you're
05:18going to get with misalignment. Whereas at the back end with the bosses that is something that often you
05:24might get just that little bit of paint or something it can really could be beneficial with a carbon frame
05:29it's not quite so expensive? No well the tooling exists for facing carbon disc brake mounts so actually
05:37facing a carbon frame in that area is no more time consuming or expensive than doing a metal frame
05:44and it's something that most frames could benefit from even if it's just to remove excess paint that's
05:49slightly misaligning the caliper and it's the the key thing is just creating a perpendicular surface to
05:56the disc so that when you're clamping that brake caliper to it it's parallel so at least your pads are hitting
06:03the rotor squarely.
06:04So if you've had a bike that's come into your workshop it's perhaps not had the best QC it's not
06:15maybe the best frame and the components haven't been running in it very smoothly what are the very
06:19common symptoms that you would see as a result? So I guess starting from the rear moving forwards
06:25obviously disc brake bosses that are not parallel and perpendicular to the disc you get the rubbing that we
06:32all have heard from time to time it's maybe slightly spongy action on the brake regardless of how well bled
06:39it is disk pad wear being very uneven is a real common symptom and then coming forward to bottom brackets
06:49creaks that can't be defined when you remove the crank arm you know in the worst case scenarios it misaligned
06:57bearing will destroy the crank axle so things to look for are when you remove the crank arm check in
07:04the axle to see if there are small scores or uneven wear patterns you know really your crank arm axle
07:12shouldn't be sliding inside the bearing the bearing should be rotating if then the bearings are misaligned
07:20then it prevents free rotation which means you'll start to get more sliding which as soon as metal
07:27slides over metal you're going to start wearing it away so you know if you've got a very expensive
07:32power crank that's an expensive mistake and then for for headsets if if the bearings in headsets are
07:39misaligned you'll either feel kind of tight spots so your steering won't be free and even
07:45that can obviously lead on to the the actual bearings pitting the races and then you get kind of indexed
07:53steering and there's no need for it you know a nice flat parallel bearing surface means that your
07:59headset should last for as long as you want to keep it you know i have a chris king headset that's
08:05over 20 years old and it's swapped from a bike to bike and it's still running as good now as
08:10almost a day i bought it so you mentioned to me earlier while we were preparing the last frame
08:15that it might be a process that people do if they're going to hold on to a bike for much longer
08:20is it fair to say that it would take some time to notice that a bike actually was presenting with
08:25these problems yeah potentially i mean you know most brand new bikes with brand new components
08:30are going to work and work fairly well and not creak straight off the production line so for a bottom
08:36bracket for instance wearing of the bearings due to misalignment is going to take a little time i
08:43would say you know if you're really unlucky and you've got a slightly non-concentric bottom bracket with
08:51separate cups that were misaligned in when they were pressed in i mean you'll feel it straight away
08:57because the the crank won't want to move freely it might have tight spots in its rotation um and if
09:04that's the case you're going to wear the bearings out really quickly within months most problems are
09:09not that bad um you know that's worst case scenario and if you ever come across that actually that's a
09:16manufacturing issue and a warranty issue so you know you shouldn't be coming to people like us to
09:23pay to get it sorted you should be speaking to the manufacturer and having that problem resolved
09:35we've talked a lot about we have talked we will talk a lot about tolerance
09:39um it will be good just to define that and also to understand i mean our videographer earlier i'm
09:44sure you won't mind me mentioning was that was asking what he was looking for when he was filming
09:48the bosses and the kind of numbers that we're talking about are not viewable to the eye right
09:54not really no no and when we're talking about fractions of a millimeter tolerance essentially
09:59refers to the amount above and below the optimum size something can be and it still work properly
10:07certain areas don't really require a high tolerance or a very small tolerance should i say
10:13other areas do need to be toleranced much more accurately to work correctly so such as an
10:20interference fit with a with a hard cup or properly aligned bearings and i mean tolerance is something
10:28that the the manufacturer would look at as part of their quality control or qc process but there are
10:34actually two sides to that the other being consistency yeah yeah with anything that the higher tolerance you
10:40want something the more laborious that process becomes and hence the more expensive also checking
10:46gear the finer the tolerance accurately measuring that becomes more difficult and hence costs more as
10:52well with most manufacturing processes the two things are to what tolerance and also a level of
11:00consistency because you always want as much as possible to have them all the same at the defined tolerance
11:07so initially actually wrote a feature about this before i came to speak to you and i spoke to
11:11several bike shops in that process it was probably about six um and it was almost a 50 50 split between
11:18those that said yes uh frames out of tolerance that need facing is a huge problem we have to do it all the
11:25time and those that said i don't know what you're talking about this isn't a problem at all i mean the
11:29cynic could suggest that it could just be down to their attention to detail um it could also be down to the
11:36brands that they're stocking what other reasons might you give or are those the only available
11:41reasons i think both of those reasons are potentially valid um i also think you know it's something that
11:47these days with mass-produced carbon frames it's not so prevalent so there's a lot of shops that may
11:53not have the experience to be able to offer that or may just may not you know want to invest in the
11:59appropriate tooling to do um metal work in in-house everything that we've accumulated through the
12:06years if you went to buy it all today would probably cost you in the region of six to eight grand and
12:13we've talked an awful lot about um about tolerances uh there's also an element of consistency in there
12:20as well and all of that comes under quality control or qc now explain to me what happens that you've
12:28worked as a consultant for brands what happens in a factory and why is it that some of them might
12:34have more stringent qc than others it's all about having a defined level of consistency and having bikes
12:43built within a certain tolerance so the more consistent and the higher or tighter the tolerance
12:50that you want the more you're going to pay because that requires more checks more consistent checking
12:56and you know how that is done within each independent factory again depends on the price so you know
13:05how you want it reported how you want the testing done how you want the calibration of the equipment
13:11done the more stringent you want to be the higher that cost is going to be so you know if you're trying
13:16to put out a 1000 pound complete carbon road frame or road bike even you're not going to be able to
13:24physically afford to have the highest levels of quality control it would make it not a commercially
13:30viable option um and it means that all those people that have now got thousand pound road bikes that
13:36are exploring the sport and getting into things wouldn't have had that opportunity so um you know
13:42there's there's a place for all levels of quality control you shouldn't always just be right at the
13:46very highest because none of us would afford to buy a bike i mean there must be a how much
13:53is a reasonable amount of quality control actually adding to the cost of a bike is it possible to
13:58put a number on that it could be anything up to 10 to 15 percent of the price of the of a bike is going
14:07towards quality control procedures at the higher level but yeah i mean i think you have to look at
14:13it as a proportion which is probably the way you would normally work out how much you can afford to
14:19spend on on your qc process and we can talk about what happens in the factory until the cows come
14:24home but it might not help a rider at home that's got a bike that's creaking or not running smoothly
14:30if someone um is watching this video and they think actually i think my bike isn't quite right
14:36what should they do so i think i think the key thing really is um you just need to go if you don't
14:42already find yourself a good experienced local mechanic and and chat to them about the issue
14:48and see what they can do for you there's lots of good experienced mechanics out there
14:54so you just find one that's going to help you out
14:58so there you have it hopefully you're riding along in blissful silence and if so good for you
15:04if not then know that it might well be worth having your frame tolerances checked and the good news is
15:09that fixing the problem might not be as expensive as you think so i hope you enjoyed this video if
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