In a bit of a quandary. I took my new frame in to the nice guys at the local independent bike shop to have the BB threads chased-through pre-build. Standard practice.
Seems the sides were slightly out of line and they've stripped the non-drive side...
They can get a BB which screws together, but they're expensive (my cost implied) and I've a new one at home that is now not needed. And a new frame that is now permanently damaged (although potentially was a QC fail at the factory? Who knows)
I don't wish to fall out with the shop, but what do I do?
Ta
They've written the frame off haven't they? Id expect a new frame.
This is what they (should) have liability insurance for. I’d be well peaved and would want the frame replacing.
Some half-cock bottom bracket is going to cost you more whilever you own the frame.
They ****ed it, they fix it. There were already threads cut into the frame, so it’s been proven that it can be done.
I’m struggling to get my head around how they’ve managed to strip threads when they were supposed to be cutting them
I'd expect a replacement frame. Even if they'd shell out (pun intended) themselves for a screw together bottom bracket, that'd make any future replacements really annoying and possibly limit crankset choices. Also I'd find it heartbreaking to live with a brand new frame that had a bodge to start with.
It should be replaced at their cost. If they're even slightly hesitant at that it would be the last time id use that place as I can't even work out how they'd strip the threads when chasing them.
A well known frame builders damaged my frame after respraying it. It was an Alloy Colnago with fluted tubing, and they managed to crush the top tube fluting slightly.
I got a new frame from them.
as I can’t even work out how they’d strip the threads when chasing them.
I can, especially if they have a high quality(sharp) tap and duff threads to start.
Hmm unlikely I'll get a new frame as it's a nukeproof...and yes it will feel a bit bodged (although the Enduro bearings version would be ok possibly) which is gutting long-term.
I don't want to fall out with the shop, and hate conflict/bad feelings. The irony is that I've spent the past 7yrs on a bike with pressfit BB and not had any bother at all...and that's with me fitting them.
Cheers for the support, let's see what happens. I've just applied the invisiframe stuff too🤦🏼
I don’t want to fall out with the shop
Um, because of the wonderful service they give you where they ruin a new frame and then expect you to pay for a workaround for the problem?
Yeah sod that. They will have liability insurance, if they're professional it doesn't need to be an unpleasant discussion. They should want to keep you as a customer. If they can't get a new frame they should pay you the value of the frame. Even that is a bit rubbish as I guess you got the nukeproof at a massive discount in the firesale so you'd not be able to get an equivalent. If they mess about this is what small claims court is good for.
I’d expect the shop to put you right - if the solution is an expensive screw-together BB, then they can supply and install one at their cost. If they don’t agree, then they can supply you with a replacement frame at their cost.
if the solution is an expensive screw-together BB, then they can supply and install one at their cost.
If I were willing to entertain a screw together bottom bracket, I'd want that, and some compensation on top.
Just replaced a Miche BB with a Shimano in my alloy Dolan. I cannot tell you how many times I checked the alignment of the NDS before ramping up the torque. Even slightly amis and those threads are toast. If you don’t love the frame, I’d take their fix. But resale the frame is now worthless. Of course the same is true of the manufacturer.
nukeproof
Could be replaceable if its one of the ones that's on the cheap list that the ex crc chap is selling as per this thread?
https://singletrackworld.com/forum/topic/possible-demise-of-crc-wiggle/page/45/
(Skip to page 45)
They can't be that nice if they're not sorting something out for you.
All may not be lost, I've salvaged BB threads that others (including manufacturers) have ****ed with a pair of these:
Clean out any bits off sticking out tube that may get in the way with a grinder. Check the faces are perpendicular and parallel, and correct with a file. Then insert the tool and proceed slowly and carefully checking with a set square as you go.
I there's not enough metal left add braze which obviously will end up with a partial repaint.
But if it's new and they've ****ed it they should replace it.
There are only two lbs around here and I've had bad experiences with them both. The positive has been that it made me get (almost) all the tools and experience I need to fix my own bikes over the years.
I'm like you op, hate conflict and try to avoid it all all costs but even I wouldn't be happy with them damaging a frame and expecting you to bail them out.
Id be pressing them to make good the damage at their cost as a minimum and never go back to them again. Not due to the damage as such (these things can happen) but trying to shift the cost onto you. That's not on and id never give them my money again.
Hope you get it resolved either way mate 👍
All may not be lost, I’ve salvaged BB threads that others (including manufacturers) have **** with a pair of these
Telling us what they're called might help us google for them
Depending on the amount & type of material around the bb shell they might be able to ream & sleeve it.
Scroll down to thread repairs.
https://argoscycles.com/resprays-refurb/price-lists/
Tarauds de boiter de pédalier Eldi. 😉
Which I Googled and got this:
The pair are probably more than our OP's frame cost.
I'm trying to work out how they're better than a normal tap set. Does the extended section centre it better in the shell?
anderzz
Free Member
Sorry what is this you had done?Every bike I’ve built I’ve just took the frame out of the box and screwed a bottom bracket into it. (or pressed if push fit).
Surely they are shipped ready to be built?
Me too but I know that a lot of people consider it good practice to have this done before a build. Different strokes and all that...
Yeah, I've never had to chase the threads of a brand new frame - or even most used frames. Maybe it was unnecessary, but it's still the shops fault.
Praxis works BB that screws together inside the BB shell is a very good bit of kit.
i ran one in a surly trucker with a stripped BB shell, for about 4 years, no problem.
Do they not have a BB tap tool? If you're in or around Exeter then I know at least one place that can help.
Is that tool not exactly what the shop used in the first place?
Given it's a a taper tap . It should be - if they were following machining principals
Often though the shop will be too cheap to buy a taper tap set and will buy a considerably cheaper thread chaser which doesn't have the lead in of a taper tap -which is fine for 90% of these kinds of jobs a shop will see - it's meant for cleaning out swarf/corrosion/paint /nipped threads in a good thread form. If the threads misformed high chance you'll only make it worse with a chaser
Does the extended section centre it better in the shell?
Yes.
Surely they are shipped ready to be built?
Some manufacturers send out perfect frames and some do not. I've never had to reach for taps when building up Look, Specialised, Giant, Lapierre... But some manufacturers send out frames that require work before they can be built up. And some manufacturers build up complete bikes with cross-threaded BBs among other horrors. The latest I've put right was a Brompton of my own. When I came to replace the BB I took the plastic cupped BB out (with difficulty) and found the aluminium-cupped BBUN72 wouldn't go in because the drive side thread wasn't in line. The above tool allowed me to correct it.
I had a policy of if it was fixable I fixed it before sale and only sent stuff back to distributors/manufacturers if it obviously wasn't going to be fixable or the fix would degrade the product. It was easier, cheaper and faster than sending stuff back.
In the case of the OPs frame it could have been Nukeproof who cut duff threads or the lbs that buggered perfectly good threads trying to chase them.
Do they not have a BB tap tool?
I mean, that's presumably what they've used to chase the threads. I can't think of another way a bike shop would do it. If you've somehow managed to completely misalign the tap, and then hamfistedly proceeded to crossthread it in, I think those threads are beyond saving.
Thanks for all the comments.
Yes I always have BBs chased through on new frames as a precaution to problems down the line with poor alignment...and seems to have caught me out at the start which is a first for me. Usually have them faced too but on this occasion it wasn't needed.
I'm not naming the shop as I genuinely believe this to be poor thread alignment and a frame made of chod. They have been apologetic and generally deal with high end kit and elite riders, so isn't from lack of experience. Doesn't give me much confidence in the rest of the frame though...
I don't think I want another Nukeproof even if one was available, so the option is a praxis or equivalent BB, or try and find another Enduro frame that will fit the shock and the pile of new parts I've accumulated...
I'll know more in the week, but does look like I'll be riding on the old bike tomorrow (thank goodness I've still got it!)
Cheers
An example of a badly alligned thread it was impossible to screw a metal-cupped BBUN72 into:
I reckoned it could be corrected with the above tap without loss of strength so did so, it's fine now.
Without too much loss of metal.
You seem to be quick to assume the frame was the issue and the shop less so. But you’ve zero proof the frame was in way the problem.
Doesn’t need be a fall out with shop. Just have the chat with them making clear it was a brand new frame which they’ve responsibility for. Unless they can prove you or frame at fault (can’t see how they could) it’s their responsibility. No need to argue your only question is how are they going to sort you out.
Unless they can prove you or frame at fault (can’t see how they could) it’s their responsibility.
If it was me, and it was a brand new frame, I'd be really dubious if there was any resistance at all putting the taps in. I'd stop and check after a couple of threads, not just keep on forcing it through.
Yes, Aidy. It's obvious really quickly if there's something amiss. It's then a question of how amiss and whether there will be enough thread left if you continue. If in doubt send it back rather than try and fail.
If you're putting in a Shimano or sram crank, does it actually matter if the BB can be done up tight (assuming there's no play when it's mounted with the cranks)? The crank will stop it coming undone anyway.
The shop that caused the damage is under obligation to make good on their incompetence. Because even if they fit a push fit BB, the damage is still there and you'll always be reminded of it.
Tell them straight to replace the frame or its small claims court.
You are owed a frame but it's impossible to say who did the damage. In a normal situation the shop would point you in the direction of pursuing a warranty, but it doesn't sound like this in an option.
The thing is.....if a bottom bracket is in perfect condition, I don't know how a BB chasing tool can wreck a frame due to the way the tool locks together. They are pretty idiot proof unless one puts the tool in the wrong way around! Some are not labelled so you have to look carefully at the threads (which is really dumb). The tool is also only really designed to clean the threads and get rid of small imperfections, not magically make a wrecked BB shell perfect again.
So if the frame was dead from the factory, the tool could potentially make it more dead than a Monty Python Parrot. Which sucks for the shop who innocently took on the job. Maybe the mechanic was too gung-ho and thought by forcing the tool, it would make everything right. Doesn't change the fact that the frame was probably faulty and not fit for use in the first place.
I'd be going after 'Nukeproof' more than the shop but I'm guessing that you can't.
The shop has messed up.
Why force the cut when meeting resistance. Always go slow at first when chasing threads.
Sorry that you're going through this matey but the shop needs to make good.
Not your fault
People seem very keen to blame the shop rather than Nuke proof. BB shells are cast, pressed or machined then brazed into the frame. That's when the first errors occur:
Check whether you chainrings are perfectly parallel to the top, down and seat tubes. Some of you may be disappointed, some may be so bad you realise you're pedalling at an angle and your chain line is shit.
Next the frame builder puts the frame on a flat surface and starts measuring and finds something isn't right. So they start "cold setting" which just means hauling on the thing to get everything in line and where it should be. During this exercise the weakest points yield, sometimes that's the BB shell which means the shell is no longer a tube with parallel walls.
Next comes cleaning up with a file and threading the BB which if the shell is already distorted isn't going to be easy or satisfactory. The tapping set will be of varying quality and rigidity, and with varying amounts of play between the parts. Add the competance of the frame builder to the equation. Some frame builders screw up due to incompetance and/or crap tools.
Duff BB allignment and/or threading was the most common frame defect I saw. Others included fork blades not parallel to the steerer, head and seat tubes not parallel, dropouts needing a file to centre the wheels...
I checked everything as I went through builds correcting minor issues as I went and rejecting anything too far out to correct. When the bike was finished I eyed up the bike from front, back and above to check everything was visually OK then took it for a spin to check it pedalled and rode straight hands off.
I like carbon bike frames. 😉
I'd say the shop should have started the job cautiously and the moment it looked like the frame was not right (assuming the frame had a fault) stopped and contacted you before proceeding.
No help now but I'd say the whole thing was unnecessary. 20 odd years ago (maybe more now) when external BBs were first a thing it was perceived they needed improved tolerances and frames manufactured for older internal BBs might not be manufactured to high enough tolerances. Particularly facing. So the habit grew in getting them done again locally prior to first building up though in reality I'm not sure it made much odds. I'd say for the last 15 years or more if you've been getting this done it's largely been an exercise is subsidising your LBS. And as said above - if it's not broken, don't fix it. LBS "mechanics" are not engineers - the **** up to success ratio is way too average to give them more work to do than absolutely necessary. Would I trust a lbs monkey over a manufacture facility - nope. And I'm cytech trained myself. To be honest I'd rather trust the lads I teach who do a day release to do an engineering apprenticeship to do the job over a bike shop mechanic. And given the other 4 days a week I rarely trust them to tie their own shoe laces I think that something about my thoughts on Cytech standards.....
