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So many things you could pick up on. Never mind its a second hand frame and there's nothing wrong with the ewings bearings design. Or the fact he didn't actually machine it properly.
The guy speaks shit to sell his products. That's it.
So many things to pick on?
Please explain how being second hand is relevant to the design flaw of leaving the BB face flush with the iscg mounts, which is very well explained by earlier posters on page 1.
He also explains why it is quite tough to machine a completed bike frame. Not sure why he didn't just machine the whole face of the plate flat though. Maybe you'd like to explain how you'd have done it.
He also quite reasonably explains how the 30mm axle in a standard shell leads to a compromise on either the bearing size or the cup walls. Didn't seem like he slams them for it.
Elsewhere on the forum right now is a thread about a new frame that arrived with chipped paint at the dropout (something that would probably happen the first time the wheel is fitted). That thread has received generally supportive feedback and hand wringing that it should have arrived in such a condition.
Yet here is a frame that has been badly designed (the ISG tabs are too close to the face of the bb shell to allow for proper facing post-welding), badly manufactured (said ISG mount is not parallel to the bb shell face) and difficult to rectify once made. And this thread has been met with outrage that the manufacturer is being somehow unfairly held to aerospace standards of engineering. Really?
Cost is not an issue here. Good design costs nothing. And at any price a parallel faced bb shell (or at least the ability to face it yourself) is not a big ask.
The thin walls of the 30mm internal BB do make the problem worse, but if the bb shell wasn’t so poorly finished it wouldn’t be an issue. The fault lies with the frame, not the bb.
Hambini is an engineer and clearly doesn’t know (or profess to know) so much about bicycles. What he does know is road biased. He is quite open about that. His delivery is deliberately unrefined and childish. He’s a shock-jock. He gets people talking. That’s the point. If you check out the videos he did a while back on GCN, he clearly knows his stuff when it’s delivered in an adult way. But let’s not let that detract from the fact that this particular frame falls short of basic manufacturing and design standards.
He's definitely an acquired taste. I think part of the reason he takes issue with Kingdom, Open, Cervelo etc is that they present the image that you ARE buying something made with a high level of engineering skill and knowledge behind it when the reality is that they are passing it off to the cheapest possible manufacturer then whacking a massive profit margin on top for themselves. As for QC, I imagine that they rely on the manufacturer doing it and throw them out the door when they land here.
but he’s certainly showing up alot of the big premium bike brands for a bunch of amateur chumps
Nope, he’s just applying un-necessarily high standards in most instances.
What he sees as catastrophic failures are, in the vast majority of cases, good enough for the intended use within a budget.
…exactly.
Really? Good enough for a £2000+ premium frame which feature in most of his video's? Is that what you'd expect and accept? So how many hours would it take if you were to trawl through the millions of lines of STW threads on bearing issues, cracked frames, warranty issues (the fact people see warranty as a bonus and selling point is telling right there). No. Wrong. Not impossibly high and unnecessary standards, just the expectation of the application of THE most basic of engineering design and manufacturing principles when you're spending upto £3500 on a plastic frame or upto £2k fancy pants metal one. Hambini has exposed that the £3500 frames have all the same basic school boy error problems than a sub £100 supermarket bike frame has. We're being ripped off by these manufacturers.
This is the problem when keen cyclists start messing about with engineering. Fine if you're a qualified and experienced engineer like Cy from Cotic is, but there is more to engineering a bike than welding a few tubes together, or laying a few CF prepreg sheets together in the shape of a bike frame.
So many things you could pick up on. Never mind its a second hand frame and there’s nothing wrong with the ewings bearings design. Or the fact he didn’t actually machine it properly.
The guy speaks shit to sell his products. That’s it.
No Alex is right. No issue with the crank and that wasn't the claim made by Hambini (did you actually watch the video??) and he says you will have 'got away with it' if you had a smaller diameter crank like a Shimano crank, that would have accommodated a stiffer BB shell. But it would just be covering up the root cause which is a crap design and crap manufacturing of the BB shell. Hambini is not speaking shit...he's exposing the scandal of the industry and he sees the same issue with all the big brands.
He is selling his products...that he has engineered to solve the problems the big manufacturers are building into their frames through shoddy engineering. It's a market created by the bike brands by their shoddy products that Hambini is exploiting. What would you do if you'd spent £3500 on a fancy pants carbon frame that requires 50w of power to turn the crank in fresh air due to a miss aligned BB shell due to shoddy manufacturing that eats bearing every 3 months. What would you do once you've been fobbed off by their warranty department and you're left with the frame and a couple of bearing that have been turned to dust? Chuck the frame or buy a Hambini BB that addresses the issue and gets you out and about with a properly performing BB and crank (other similar BB's are available of course so he's not the only person on this issue).
Hambini is a bit of a Pratt no doubt, but look beyond the crass exterior to what he's actually saying and he's bang on. I know it's very unlike STW to look beyond the person to the meat and veg of what's being said - the pitch forks have already been sharpened and thrust long before anybody actually listens to what's being said being the usual STW approach...but if you can bring yourself to actually listen and comprehend what he's saying you'll learn something from him. You wont like him any more, but you'll be better informed.
I've never watched this chap before.
I dislike his presentation style and potty mouth. For that I won't watch again.
He did however seem to make a few valid points. IANAE.
I agree with some of his points.
the point i was making with it being second hand is you dont know how many times that isg tab has been smacked and possibly bent or the bb shell dragged across rocks etc etc.
The point about the bb was that he had to machine a spacer for it and that CC had made it difficult for people to replace the bearings. No they havent. Its just sounding like they are trying to pull a fast one.
Id stick it on an adjustable table I agree its difficult to fix.
At the end of the day most frames are fabricated in some way or have a potential for error due to the way they are produced. These errors are actually quite large.
Im not saying we should accept crap and its good that someone is able to ague the side of the customer but i do think its over the top and unrealistic in many circumstances.
Once upon a time i bought an Ibis frame. After 3 years the headset cups broke away from the frame itself. The clearnce hole was double the tolerance it should have been. Thats why it failed.
2 pure offered go bond the old cups back in. I declined, made my own cups at work that adressed the route cause of failure and had them bonded back in by a professional.
High end frame QC is shit. Hambini is highlighting this and rightly so. If youre spending 3k on a frame you want the design spec to be at least in the ballpark.
I watched one of his vids where he had a carbon road frame with a push fit bb that 0.1 out of tolerance. Thats just awful. Id be fuming if i bought that.
These aren't ridiculous tolerances.. theyre bog standard. There's wriggle room but thats taking the piss out of the customer imo.
Hambini fan or not For someone working out of his garage in his spare time, he has fixed some rather shonky frames with well engineered solutions. And by shonky they are millimeters out not microns/thou out.
that is true.
though saying that, he's a classic example of survivor/selection bias with QC in the bike industry.
I watched one of his vids where he had a carbon road frame with a push fit bb that 0.1 out of tolerance. Thats just awful. Id be fuming if i bought that.
Genuine question, 0.1mm out of tolerance or 0.1mm from the stated size. A pf92 bb is +0.1mm - 0.0mm tolerances so entirely possible that 0.1mm was acceptable. But I digress.
No issue with the crank and that wasn’t the claim made by Hambini (did you actually watch the video??) and he says you will have ‘got away with it’ if you had a smaller diameter crank like a Shimano crank, that would have accommodated a stiffer BB shell. But it would just be covering up the root cause which is a crap design and crap manufacturing of the BB shell.
There is the bigger problem, the machining on this particular frame could have been wonky but well within spec, with a normal bb that wouldn't be an issue. The design (and therefore tolerances) of that threaded shell are donkey's years old, it predates external bb and certainly 30mm external bb. Those newer designs don't allow for wide variations in production. They cram more and more into the same space and remove the room for error so a BSA30 bb doesn't actually fit a threaded shell at the upper limits of spec. That's not a problem with the shell that's a BB problem, that's designing product a to work only with good examples of product bb.
Yes the frame might be badly built, it might be absolutely at the widest end of the design spec for the bb, seat tube, shatner's bassoon but if it's in spec and the kit bolted to it doesn't work because it requires a more stringent spec that's not a problem with the frame, it's a problem of incompatible parts, in this case through poor design of the BB not accounting for the acceptable tolerance of the established design its supposed to fit.
Hambini has an acquired taste, he's a lot more restrained than he used to be, its about time someone publicly called out the piss poor level of engineering and manufacturing in the cycling industry.
Nope, he’s just applying un-necessarily high standards in most instances.
Bearings have tolerances in order to work correctly, its not for the end user to choose, its stipulated for them. I've had a few frames where the bearings were being pinched by the frame, causing premature wear.
There are too many "Standards" (Shit ways of doing things) in the cycling industry, how can the 3rd party manufacturers keep up and deploy these effectively? There needs to be a cull of the shit ones, pick the best and go forward, improve on them if needed. Superboost and DUB spring to mind!
https://www.bikeradar.com/features/opinion/bike-industry-mtb-standards/
Once upon a time i bought an Ibis frame. After 3 years the headset cups broke away from the frame itself. The clearnce hole was double the tolerance it should have been. Thats why it failed.
I replaced the bearings on a ibis headset, quite surprised they'd used brass self tappers to hold the headtube badge on, it had made a bit of a mess of the inside of the headtube where they'd punched through. Wonder if they'd put the screws in the FEA model, highly unlikely, they've probably never had a headtube failure, but it looks shonky.
Swearing is rarely pointless. Enjoyed that. What a rubbish frame.
There is the bigger problem, the machining on this particular frame could have been wonky but well within spec, with a normal bb that wouldn’t be an issue. The design (and therefore tolerances) of that threaded shell are donkey’s years old, it predates external bb and certainly 30mm external bb. Those newer designs don’t allow for wide variations in production. They cram more and more into the same space and remove the room for error so a BSA30 bb doesn’t actually fit a threaded shell at the upper limits of spec. That’s not a problem with the shell that’s a BB problem, that’s designing product a to work only with good examples of product bb.
Yes the frame might be badly built, it might be absolutely at the widest end of the design spec for the bb, seat tube, shatner’s bassoon but if it’s in spec and the kit bolted to it doesn’t work because it requires a more stringent spec that’s not a problem with the frame, it’s a problem of incompatible parts, in this case through poor design of the BB not accounting for the acceptable tolerance of the established design its supposed to fit.
No, you've fundamentally misunderstood the issue with this frame. If the bb faces are not parallel to the centreline of the bike and cannot be made parallel with standard bb facing tools you have failed to design and properly construct a bicycle frame at a very basic level.
If you want to design and produce frames that cannot be faced later you need to make sure they leave the factory pretty close to bang on and have sufficient quality control to ensure they all are within acceptable tolerance. It is far better to ensure that the BB face is proud of all obstructions so it can faced later with relatively simple and widely available handtools if required.
But thats half the point. It could well have left the factory "bang on"
I don't see damage in use as a likely cause of this defect. It would take a fairly massive force to bend the BB shell and plate about a mm over a relatively short distance and there's no evidence of any damage to the ISCG tabs or the shell, or indeed to the rest of the bike. You wouldn't just see it on the face.
Of course, if you leave the face proud you could easily rectify that little aspect of the problems you'd when the frame is run over by a truck 🙂
have sufficient quality control to ensure they all are within acceptable tolerance.
According to one of the posts back there Kingdom said it is in acceptable tolerance so it doesn't need post manufacturing machining to get within that.
That's my whole point.
It needs machining not to get within tolerance but in order to work with parts designed for smaller tolerances.
If you want to design and produce frames that cannot be faced later you need to make sure they leave the factory pretty close to bang on
you’ve fundamentally misunderstood the issue with tolerance, they're established, they're part of the design, they're standardised. You don't need to be "pretty much bang on" you need to be within tolerance. If that's (for argument sake) 200mm +10mm and -0.0mm a part at 208mm is "pretty much bang on" a part at 199.9mm is not.
There will be an acceptable range of alignment from 0 degrees for that bb threading, if it's within that range but doesn't work there may be a design issue with the bike* but not a QC issue.
*(I'd be absolutely amazed if that's not specified in the design of the bb)
There needs to be a cull of the shit ones
yeah, good luck with that
A BB shell's faces need to be parallel to about .01mm (= bang on, if you like). That one is at least 1mm out.
First time I've seen any of his vids- might well be the last.....
He makes some good points, the fact that Ti is pain to work with you would have thought that tolerances etc. would be more stringent as rectifying after the fact (like an ali or steel frame) is extremely difficult. The location of those ISG tabs is shocking.
All valid points too about how thin the walls of the thread on the cup had to be, and I'll echo some of the comments above - I don't think he was having a pop at CC (other than the spacer behind the bearing) as they can only work with what we all have as a BB shell.
How many of us actually chase/face a BB shell when we get a new frame?
I've never done it in anger, only time has been on my Cytech Level 2.
He claims to be well respected in Aero and Auto engineering on his website (and also autistic) - wonder how he presents himself in those environments.....
But thats half the point. It could well have left the factory “bang on”
Not bang on but perhaps "in tolerance".
It can't be "bang on " because of the poor process design. You can't weld Ti and it not deform ... just hope it doesn't deform out of tolerance and if it does scrap/recycle or what???
The fact it is out in sphericity, alignment and facing strongly suggests it left the factory that way.
How many of us actually chase/face a BB shell when we get a new frame?
As Ben pointed out we shouldn't have to.
I can't imagine him letting one out that needed facing or then claiming "it's within tolerance"
I think the interesting thing from a lot of his videos has been the relative praise for some less expensive direct from factory frames Hong Fu/Deng Fu I totally get his despair that marketing/Branding are being used to justify poorer quality from what are perceived as higher quality manufacturers.
If your paying sale £3k for a carbon frame I'd say you've got a level of expectation that the QC you're getting is better than one that comes direct from a factory for a fraction of the price.
If you're not paying for quality and only branding/marketing I'd argue something is very wrong.
There was a great article I read a few years ago from I think Chris Cocalis at Pivot who talked about the premium you apparently got with big brands was QC at varying stage of the manufacturing life cycle.
If that isn't happening there's a problem I guess?
I always chase and face, ever since forever.
But I am old and can remember when road frames were steel and chromed and absolutely needed facing.
I don’t see damage in use as a likely cause of this defect. It would take a fairly massive force to bend the BB shell and plate about a mm over a relatively short distance and there’s no evidence of any damage to the ISCG tabs or the shell, or indeed to the rest of the bike. You wouldn’t just see it on the face.
I've knocked a BB out of true after landing on the bashguard (a steel one) on an old hardtail. Thought I'd bent the cranks until the bike shop put a ruler against the seat tube and showed it twisted. No obvious cracks in the paint to show it had bent but it was definitely not right! This was back in the days of square taper BB's and the bashguard being clamped in place by the BB so not as strong as the ISCG mounts, wrote off the frame.
That's why they call them Chain Guide mounts
Bash guards have a habit of knackering frames.
You really shouldn't (need to) face a BB shell. They should be faced post welding or painting (depending on the material/finish) to the specific width +- not a lot, and left as it is. Facing will remove material that is meant to be there - not all cranks play nice with undersized BB shells. It should be obvious whether a BB face is faced or not. It will have a totally different finish (usually raw but could be finished with something else) if its a painted frame, or if unpainted you'd expect an obvious ground/milled area.
Whether you spend £300 or £3000 on a frame this should all be done before you get it - if its not, send it back!
If its a carbon frame then you're subject to a different set of finishes, even for alu shells in carbon, it's not so obvious if its been or even needs refinishing.
I see that the ISCG tab placement has been poorly designed and executed, is he saying that the consequent inability of the drive side BB to be fully inserted is causing premature bearing wear? Made worse by the BB design in this case.
I think I see the problem, but am struggling to see the justificatiion for CNC milling time.
Unless it was noisy, then I'd have to smash it to bits with a hammer
I see that the ISCG tab placement has been poorly designed and executed
Not if you want your ISCG perfectly aligned to your BB its not.
Its all swings and roundabouts.
The design allows you to mill the face of the BB and ISCG all in one, giving you perfect alignment of BB, Chainring and chain guide. If thats done at the factory, you can move on as you're never going to touch it again and so it becomes moot whether you could face it again. Welding them on later set back might mean they're miss aligned, and all its allowing you to do is a job you should never need to do anyway. Machining them as a single unit is nice but costs way more.
Each has its advantages. For every solution there's usually a compromise somewhere else.
I got bored at 12 minutes having listened to his drivel about how hard it is to face the driveside bb and iscg mounts. He is clueless. It is very easy for any basic machine shop. This method works - I've done it.
You clamp a 3 jaw chuck flat to the miller table - Jaws facing up. Pick some Jaws that will go inside the bb shell.
Place frame on it nds down. Clamp bb bore using chuck. So you are directly gripping the bit you want to machine (so it is very rigid). It also holds it nice and flat / perpendicular (directly to the the datum he mentioned). You can then also support the other places he mentioned just to stop them twanging around (but the main clamp and alignment is already done).
Or just use a Shimano UNxx bb and have none of the sealing or alignment issues 🙂
I generally swear a lot and I find his videos excessive as a lot of his language appears to be more Tourette's than contextual.
His points in the this one though are interesting for me as my hardly ridden Ibis Ripmo has a similar issue with the drive side crank feeling like it clunks as it goes over TDC.
All brand new and only with a couple of hundred dry miles on at most. 30mm DUB with a Hope thin walled bottom bracket too, so I'll look at this alignment closely when I can finally undo the bloody crank arm.
DUB isn’t 30mm / it’s about 29mm bar a tiny .01 or something like that. Has the Hope bb got a spacer in it to take up that slack? If not that might be part of your clunk.
Yeh it’s there. Cost £15 iirc for the adaptor. Forgot it was 28.9mm not 30mm
Will be having a closer look next week, maybe even tomorrow if I can get my backside in gear.
The frame is clearly all to cock. But it did sort of amuse me that he installed the BB spacer on the non drive side, and didn't use anti-seize when installing the BB into a Ti frame...
The Shimano spacers are plastic so they deform and 'correct' tolerance issues like this. Granted they probably wouldn't correct this amount of muppetry. A couple of beers, a file and some sandpaper could probably result in a plastic spacer being roughly the right shape to work though.
https://road.cc/content/news/shockjock-vid-seeks-refute-sexism-claim-reinforces-it-272869
He’s a horrible little man and I won’t give him the time of day
Makes me wonder if there's a market for a set of go/no go gauges for various bottom brackets. Perhaps even make them deeper and then with an accurate bore and a ground shaft, see how well a pair of them line up.
If bottom brackets are as badly made as some of these, it would be nice to know before building up a frame.
If bottom brackets are as badly made as some of these, it would be nice to know before building up a frame.
In all the time you've been riding bikes how many do you personally know of where it's been a problem? I can't think of 1.
I can think of maybe high double figures on the internet but as a population sample that's like as not 0.
As a rider/owner I wouldn't buy your gauges for the same reason I've not got personal meteor or lighting strike insurance and any manufacturer should have one already
Not a fan of his approach (the zyklon B comment was uncalled for, and his fixation on MAB is cringy) but I like the engineering explanations and frame analysis.
The alignment on that BB is pretty shocking, and it should be correct. It shows a poor QA process from the manufacturer.
He’s a horrible little man and I won’t give him the time of day
Yep.
though saying that, he’s a classic example of survivor/selection bias with QC in the bike industry.
There is a bit to this, but it ultimately it shouldn't leave the factory, or should be rectified by the manufacturer (albeit I'm not sure they were given the chance in Kingdoms case)
The OPEN frame was an interesting example. Assuming that there isn't some lying going on with OPENS response, and regardless of how Hambini approached it, OPEN look foolish by saying 'we don't build to a standard for the BB' - i.e. we don't really care if your BB will perform correctly.
Having spoken to composites NDT specialists about assessing carbon frames in the past, I do query his NDT analysis - you need a benchmark to assess against.
Erm, he might be right about the frame and a good engineer but is he someone I would want to promote or give money to?
Not really based on why was reported by a female journalist.
https://ridewriterepeat.com/2020/06/05/six-bloopers-of-being-a-woman-in-the-cycling-industry/
Makes me wonder if there’s a market for a set of go/no go gauges for various bottom brackets. Perhaps even make them deeper and then with an accurate bore and a ground shaft, see how well a pair of them line up.
If bottom brackets are as badly made as some of these, it would be nice to know before building up a frame
If the frame is bad enough to cause a problem, I think you would notice it during installation...
I'd like to think I'd notice during building, but clearly some people haven't. And if it's true that some manufacturers are trying to claim a wider tolerance, perhaps a shop doing a lot of custom builds might like to know before getting too far into the build.
Having said that, I've only ever owned one bike (well, two frames of the same bike) with a pressfit carbon bottom bracket and the bottom bracket was about the only part that wasn't out of spec or poorly made.
But thats half the point. It could well have left the factory “bang on”
In this case the NDS was out as well - the thread bore isn't parallel with the shell (or not faced correctly on both sides). You can't cause that through damage.
It is a sample size of 1 for Kingdom, so they need right of response (although he said he contacted them weeks ago...?) and bad BBs will float towards Hambini for obvious reasons. However, the fact that he seems to have any sort business in selling BBs to repair the symptoms of this sort of problem indicates that poor QA is an issue in the bike industry.
If I buy a frame that has an X BB, I should be able to buy an X BB and it will fit as designed. If it doesn't (and presuming the BB isn't at fault) then the frame is defective and the manufacturer should repair, replace or refund.
I’d like to think I’d notice during building, but clearly some people haven’t. And if it’s true that some manufacturers are trying to claim a wider tolerance, perhaps a shop doing a lot of custom builds might like to know before getting too far into the build.
To be fair thats true. I think a shop should have to think about something like this otherwise it's harder to identify faults. Misalignment isn't very easy to do though.
If a product requires home QA it identifies a serious issue across the industry.