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
00:10cycling enthusiasts and pros alike.
00:14Very often we look at the components instead of the frame when we're looking for a solution
00:19and that might well be an error.
00:21Bottom brackets, disc brake mounts were designed to be seated in frames that are up to the
00:25job and unfortunately that isn't always the case straight from the factory.
00:30And that's where facing comes in.
00:32This is the process of removing excess material to ensure that holes that are meant to be
00:36round are in fact round and surfaces that are meant to be flat are flat.
00:41We're here at Velo Italia up in Warwick to face this frame and see what a difference
00:45that extra step of TLC can make.
00:54Co-owner at Velo Italia, Lee Prescott, has been designing and manufacturing frames for
00:5937 years.
01:01He designs and manufactures his own Meteorworks metal frames as well as working with partners
01:05creating carbon frames such as Fesca and Open and also servicing frames from a great many
01:12brands using lots of different frame materials.
01:14Now he tells me that he never builds a frame up without first checking the tolerances and
01:19then facing, reaming and tapping if it needs it.
01:23Now tell me why that is.
01:24We wouldn't even dream of not facing and reaming and tapping all the interfaces on the frame
01:31because it simply makes the build easier and more efficient and it means that all the parts
01:36will last longer and just work more efficiently.
01:38Okay so you've got a brand new frame that's just come in or it's a frame that's come in
01:42for a really high level service and you've stripped it all off and you're going to check
01:46each of the elements of the frame to prep it before building it.
01:49Just 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
01:59is making sure that they are both parallel to each other and also creating a face that
02:05is perpendicular to the disc rotor so that the pads hit it squarely.
02:11Then with the bottom bracket what we're doing is ensuring if it's threaded that all the
02:16threads are free and clear and round so that the threaded bottom bracket will go in nice
02:22and easily without damaging any threads.
02:25But most importantly we're making sure that the faces on each side are both parallel to
02:31each other and straight and flat so that any cup that's biting into it is pushing in level
02:37and maintaining a level of parallelism.
02:40With the headset we're facing the surface that the bearing is going to mate to so whether
02:45that's an external headset, a zero stack headset or an internal headset we're braiding
02:51those faces so that they are parallel to each other and ensuring that they're round as well.
02:57That way the bearings sit in alignment and prevent any excess wearing of the bearing.
03:09Facing, reaming and tapping are generally associated with metal frames and less so carbon
03:15frames which are made in a mould and in theory should be up to spec and shouldn't really need it.
03:22Why might you need to face, ream or tap a carbon frame and is it something we should perhaps see more of?
03:29So you're right, it's much more prevalent on metal frames because on a metal frame you
03:33have to overcome any warping or distortion that's happened during the welding process.
03:39On a carbon frame, as you say, they come out of very expensive moulds that are built to
03:43very high tolerances. So most of the time, providing all has gone well with the build,
03:49the layup is in the right place, the shrinkage has happened at the appropriate rate, the humidity
03:54they were built at, you know, all these factors that need to be controlled and are controlled
03:58in good quality factories should mean that the frame comes out in a pretty good state
04:04and then any final fine finishing can be done at the factory just to polish up areas that need
04:10a higher tolerance. So it's less required typically on carbon frames but where the issue
04:16arises 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
04:36and that's when you get bearings that are not concentric and parallel and that's what
04:41leads to excess wear and the dreaded squeaking and creaking. And one way to deal with that
04:47might be facing it in terms of the bottom bracket. There are probably more cost-effective
04:52options available, right? Yeah, absolutely. Unless it's wildly out, in which case it's a manufacturing
04:58defect and should be under warranty anyway, you can normally get around a lot of these problems
05:03by the use of a good quality bottom bracket that's connected in some way. So, you know,
05:08something like this that screws together with a very fine thread that maintains the concentricity
05:14and parallelism of the bearings so that reduces any issues you're going to get with misalignment.
05:19Whereas at the back end with the bosses that is something that often you might get just that
05:25little bit of paint or something it can really could be beneficial with a carbon frame. It's
05:29not quite so expensive? No, well the tooling exists for facing carbon disc brake mounts so
05:37actually facing a carbon frame in that area is no more time-consuming or expensive than doing a
05:43metal frame and it's something that most frames could benefit from even if it's just to remove
05:48excess paint that's slightly misaligning the caliper. The key thing is just creating a
05:55perpendicular surface to the disc so that when you're clamping that brake caliper to it
06:00it's parallel so at least your pads are hitting the rotor squarely.
06:10So if you've had a bike that's come into your workshop, it's perhaps not had the best QC,
06:14it's not maybe the best frame and the components haven't been running in it very smoothly,
06:19what are the very common symptoms that you would see as a result?
06:22So I guess starting from the rear and moving forwards, obviously disc brake bosses that are
06:28not parallel and perpendicular to the disc, you get the rubbing that we all have heard from time
06:34to time, it's maybe slightly spongy action on the brake regardless of how well bled it is,
06:41disc 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
06:56misaligned bearing will destroy the crank axle so things to look for are when you remove the
07:02crank arm, check in the axle to see if there are small scores or uneven wear patterns, you know
07:09really your crank arm axle shouldn't be sliding inside the bearing, the bearing should be rotating
07:17if then the bearings are misaligned then it prevents free rotation which means you'll start
07:24to get more sliding which as soon as metal slides over metal you're going to start wearing it away
07:29so you know if you've got a very expensive power crank that's an expensive mistake and then for
07:36headsets if the bearings in headsets are misaligned you'll either feel kind of tight spots
07:43so your steering won't be free and even, that can obviously lead on to the actual bearings
07:50pitting the races and then you get kind of indexed steering and there's no need for it, you know a
07:55nice flat parallel bearing surface means that your headset should last for as long as you want to keep
08:02it, you know I have a Chris King headset that's over 20 years old and it's swapped from a bike to
08:08bike and it's still running as good now as almost the day I bought it. You mentioned to me earlier
08:13while we were preparing the last frame that it might be a process that people do if they're
08:18going to hold on to a bike for much longer, is it fair to say that it would take some time to notice
08:23that a bike actually was presenting with these problems? Yeah potentially, I mean you know most
08:28brand new bikes with brand new components are going to work and work fairly well and not creak
08:34straight off the production line. So for a bottom bracket for instance, wearing of the bearings due
08:39to misalignment is going to take a little time. I would say you know if you're really unlucky
08:45and you've got a slightly non-concentric bottom bracket with separate cups that were misaligned
08:53when they were pressed in, I mean you'll feel it straight away because the crank won't want to
08:59move freely, it might have tight spots in its rotation and if that's the case you're going to
09:06wear the bearings out really quickly within months. Most problems are not that bad, you know that's
09:11worst case scenario and if you ever come across that, actually that's a manufacturing issue and
09:18a warranty issue. So you know you shouldn't be coming to people like us to pay to get it sorted,
09:24you 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
09:39and it will be good just to define that and also to understand, I mean our videographer earlier,
09:44I'm sure you won't mind me mentioning, was asking what he was looking for when he was
09:48filming the bosses and the kind of numbers that we're talking about are not viewable to the eye
09:55Not really no, no, I mean 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 hard cup or properly aligned bearings. And I mean tolerance is
10:27something that the manufacturer would look at as part of their quality control or QC process
10:33but there are actually two sides to that, the other being consistency. Yeah, with anything
10:38that the higher tolerance you want something the more laborious that process becomes and hence the
10:43more expensive. Also checking it, the finer the tolerance accurately measuring that becomes more
10:50difficult and hence costs more as well. With most manufacturing processes the two things are
10:57to what tolerance and also a level of consistency because you always want as much as possible to
11:04have them all the same at the defined tolerance. So initially actually wrote a feature about this
11:09before I came to speak to you and I spoke to several bike shops in that process, it was probably
11:14about six, and it was almost a 50-50 split between those that said yes, frames out of tolerance that
11:22need facing is a huge problem we have to do it all the time and those that said I don't know what
11:26you're talking about this isn't a problem at all. I mean the cynic could suggest that it could just
11:32be down to their attention to detail, it could also be down to the brands that they're stocking.
11:37What other reasons might you give or are those the only available reasons? I think both of those
11:42reasons are potentially valid. I also think you know it's something that these days with
11:48mass-produced carbon frames it's not so prevalent so there's a lot of shops that may not have the
11:54experience to be able to offer that or might just may not you know want to invest in the appropriate
12:00tooling to do metal work in in-house. Everything that we've accumulated through the years if you
12:07went to buy it all today would probably cost you in the region of six to eight grand. And we've
12:13talked an awful lot about tolerances, there's also an element of consistency in there as well
12:20and 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
12:34might have more stringent QC than others? It's all about having a defined level of consistency
12:40and having bikes built within a certain tolerance. So the more consistent and the higher or tighter
12:49the tolerance that you want the more you're going to pay because that requires more checks,
12:55more consistent checking. And you know how that is done within each independent factory again
13:03depends on the price. So you know how you want it reported, how you want the testing done, how you
13:09want the calibration of the equipment done. The more stringent you want to be the higher that
13:14cost is going to be. So you know if you're trying to put out a £1,000 complete carbon road frame
13:21or road bike even you're not going to be able to physically afford to have the highest levels
13:27of quality control. It would make it not a commercially viable option and it means that
13:33all those people that have now got £1,000 road bikes that are exploring the sport and getting
13:38into things wouldn't have had that opportunity. So you know there's a place for all levels of
13:43quality control. You shouldn't always just be right at the very highest because none of us
13:49would afford to buy a bike. I mean there must be a how much is a reasonable amount of quality
13:54control actually adding to the cost of a bike? Is it possible to put a number on that?
14:00It could be anything up to 10% to 15% of the price of a bike is going towards quality control
14:09procedures at the higher level. But yeah I mean I think you have to look at it as a proportion
14:14which is probably the way you would normally work out how much you can afford to spend on your QC
14:20process. And we can talk about what happens in the factory until the cows come home but
14:24it might not help a rider at home that's got a bike that's creaking or not running smoothly.
14:30If someone is watching this video and they think actually I think my bike isn't quite right
14:36what should they do? So I think the key thing really is you just need to go if you don't already
14:42find yourself a good experienced local mechanic and chat to them about the issue and see what
14:49they can do for you. There's lots of good experienced mechanics out there so you just
14:55find one that's going to help you out. So there you have it. Hopefully you're riding along in
15:01blissful silence and if so good for you. If not then know that it might well be worth having your
15:07frame tolerances checked and the good news is that fixing the problem might not be as expensive as
15:12you think. So I hope you enjoyed this video. If you did then do hit the like button. Let us know
15:18what you thought in the comments and subscribe if you'd like to see more of our videos.