Forum menu
Thinking about it, the times that I've found it loose on the bolt it is highly likely that is is because I've hit my derailleur on something. That's definitely happening more often now that I'm on a bigger, faster bike.
Same with my mate to be honest, he tends to smash through things.
It's a reason that I'll upgrade to Transmission for my next drive train.
You note on this thread its those who use torque wrenches have bolts coming loose.
I'm thankful for having a mate who's an aircraft engineer. He checks my torque wrenches on his fancy calibration device in his work hanger.
Brand new X-tools one a few years ago was way off out the box. Thus far my Halfords ones have served me well.
Not quite bits falling off but recently bought an ebike with gx axs gears, of 12 only about 5 were indexed properly, the rest were all over the place. I was going to take it back but thought it was something that would be handy to know so watched a few vids on YouTube and got it sorted myself, then refused the offer of a free six week check up by the shop where I bought it
I'd expect everything to be built correctly. I wouldn't trust everything to be built correctly. I've had this happen to friends numerous times (and me). Things do come loose but some shops just aren't very good at what they do. Not everyone gets a bike back from a shop and checks it over, why would they, they've just paid someone to sort it?
If you say something never happens, it only takes one counter example to prove you wrong.
What he actually said was:-
Properly specced. prepped and tightened bolts just do not come loose.
Which is absolutely true, as long as you expand it to include the things being bolted together.
The number of people on here (and everywhere TBH) who will swear blind that they "did it up properly" despite the thing falling off after three rides is indicative of the number of people who have no idea what "done up properly" actually is. And that includes a lot of shops, and scarily enough, a handful of manufacturers.
Only time i have things fall off my bike is when i've rushed and not done it properly. Or had a shop work on something.
The mechs on my DH bikes come loose frequently. I can tell as the shifting goes to garbage when the bolt is loose.
Torqued and locktighted.
They do come loose if ride hard.
Just remembered - the tiny bolts that hold the dropouts to the frame on my Shand did come loose. However I had not checked them and have since removed them, cleaned them and loctited them. Not come loose again. I assume undertightened when the bike was built up and there was no loctite on them
How are you buying from a physical shop if they are sending the bike to you? That's still mail order from somewhere you can't visit easily.
If I buy from an online shop I always PDI it myself. From a physical LBS probably wouldn't but then Id only use the LBS after building a relationship with them and trusting their work. Any shop worth it's salt would give the bike a check over a few rides after purchase just to check for things like this.
Buying online because it's cheaper means you need to take some responsibility for the checking of the bike imo. The reason it's more expensive from a walk in shop covers this valuable service.
Am I at fault, or poor PDI, bearing in mind nothing was correctly torqued when I got the bike? Thoughts?
And
Once you noticed the caliper bolts were loose, checking everything would have been sensible.
Is, I think, the start and finish of this particular tale of woe. Hope it's not trashed and you get the mech working again.
I never use locktite either.
The service instructions on my Bike Yoke dropper require it's use.
I never use locktite either
Erm, dropout bolts?
I just every so often do a quick is it tight check. Same as a garage telling you to check car wheel nuts after 30miles or so. In fact I've had a quick check and continental suggest this after a tyre change.
And both Shimano and SRAM rotor bolts are pre-loctited
i’d be inclined to say that the bike wasn’t PDI’d. a month seems like an unreasonably short time for a correctly fitted mech to work itself loose.
all you can do is raise it with the shop. do you still have the paperwork that confirms that a PDI was undertaken?
nickc - hence my correction 🙂 I don't buy either shimano or sram rotors and use copaslip on the bolts when reusing old ones
OP, you did say something like "I've never seen a mech come loose" but in fairness that's not how a nut and bolt check should work, it should be "is this a nut or a bolt? Yes? Then I will check it". If you're only checking faults you've seen before you're always going to be leaving yourself wide open.
It does sound like it might not have been done well by the factory/shop though.
of 12 only about 5 were indexed properly, the rest were all over the place
On my GX AXS when you micro adjust one gear it’s the same adjustment for all of them. It just shifts the derailleur by 0.5mm each time electronically. It doesn’t do a different adjustment for each gear. You basically, put it in the noisiest gear and dial out the noise.
I never use locktite either.
However I had not checked them and have since removed them, cleaned them and loctited them. Not come loose again. I assume undertightened when the bike was built up and there was no loctite on them
The case for the prosecution rests, Your Honour
Hence my correction
When the mech hanger has one of those tiny bolts to the side, they can often come loose and need the blue.
After 2 years with a Marin SQ3 I am on mech hanger number 3. I eventually started taking a spare out on rides just in case. If it comes loose, the rear mech B screw grinds a hole through the hanger.
Really bad design. Got a couple of frames here with the SRAM UDH hanger, they're nice and sturdy, functional design, so likely won't have the same issue.
Mail order bikes need to be checked as if they’ve not been PDI’d, then take it to your LBS for a check over after a couple of months or less if it’s been used a lot.
One of my mates had the rear brake caliper fall off (and obvs lose the 2 bolts) part way down the 1st decent on the 1st ride of his new shiny SC Bronson. Forced him to check the front before going steadily back to the car ... front was loose too. Unbelievable from a bricks and mortar shop.
I ALWAYS check everything myself. As per another poster - even the Shand when it arrived (no problems there !!)
Hence my correction
I don’t understand why you have loctite if you never use loctite except when you use it?
sometimes I wonder if you argue the point for the sake of being contrary.
And yes I’ve had a rear mech come loose a few times. Probably because I didn’t tighten it enough. I use loctite sometimes, depends if I can be bothered to find it in my mess. But I only work on my bikes.
Sometimes?
I was feeling charitable 🤣
Must have shifted like an absolute dog if the mech was that close to coming off
^^That was my first thought, if it was a day or two after you took it home maybe, but a month after?
I do think there's a need for users to develop a bit more mechanical sympathy and sensitivity to when something doesn't feel/sound/work right and just stop and check.
I've been out riding with mates who were oblivious to loose cranks, headsets and even wheels!
TBH such people are potential show stoppers for themselves and anyone they ride with and I'm not keen to go riding with someone so unprepared.
After a month of use I'd say all bets are off on bolts remaining done up, and if you only tighten odd things when you happen to notice they're loose then you will miss something else, spot one thing do the lot.
There's a lesson for Junior in all of this and it's not about LBS liability.
If the bike is important to him and he doesn't want his rides and finances ruined by catastrophic sudden disassembly then he needs to get in the habit of checking all of the fixings on his bike for himself on a regular basis.
Modern mechs still shift surprisingly well even if they're half hanging off.
So, reply from the bike shop pretty much as expected.
- all nuts and bolts must be checked prior to each and every ride,
- and if you did not do that, its your fault.
- it's a cheapo mech on the bike (Deore) so you should have expected it to rattle itself off
- and this is the funny one which is utter rubbish- "you will also find pre-set torque settings are for an ideal environment at ideal conditions. Generally in real world testing the rider will adjust correctly if components are coming loose"
So, in short, a PDI is a waste of everybody's time if the onus is on the buyer to check everything. Just imagine if you had to quickly nip round every nut and bolt on your car after you drove over a cobbled road to prevent the car from falling apart!
Teaching mechanical sympathy to a 14 year old is a great idea, however not fair to place the burden on somebody of that age - I'll put myself in the camp of checking our fleet of bikes prior to most outings, especially safety critical items, but when Jnr nips out for a quick lap of the local woods with a pal, that's not always going to happen. And, no I didn't check the mech as I've never had one come loose, shall add that to the list though.
My advice to me is to buy from an online retailer, where my guard is up more and not go to an LBS, who in this case shipped the bike to me post PDI, to save a trip during a busy work week. Fortunately no significant harm done, and I used the opportunity to teach Jnr how to split and replace a chain, how to setup a new mech, how to use a torque wrench and where to apply loctite blue (and not to ever the loctite 638 I have on the shelf).
in their defence (just a little bit) when our Trek Session arrives tomorrow even though they've been brilliant on discussions, emails, etc, i will still check each and every bolt before i send the lad out on it.
Jeepers guys. I bought the loctite for that job. Its not that difficult to imagine
At that i would name and shame the shop. We all know their pdi was crap and that response is crap.
Yes they have no legal obligation but something like a free or at cost mech and free labour on a wheelbuild would have been a nice goodwill gesture at very little cost to them
Instead of gaining a loyal customer they lose one
Despite agreeing that it is probably advisable to check a bike over before using unless it comes from someone you trust, that would be one LBS I wouldn’t be using again. At the very least I would expect a goodwill gesture, perhaps a new mech and chain at cost price or a low value voucher - 20 quid or something. It’s a competitive world out there and it ain’t the pandemic anymore - customers no longer grow on trees….
Edit - lol snap Tj
So, in short, a PDI is a waste of everybody’s time if the onus is on the buyer to check everything.
I've never not gone over a bike with a torque wrench at least every couple of months and I do a version of the M check before every ride, and TBH (although its an extreme example) I've held a 40mm stem that was twisted by a pro DH rider . So I'm willing to bet that their torque settings for things like levers and stem bolts are probs a wee bit more than mine need to be.
I had a problem with the shock on my new bike in the shop (a very respectable chain), asked in the shop, was told "They're all like that mate" and believed them.
Turned out that there was a problem, also with the fork. But by the time I confirmed it, I'd already ridden the bike for almost a year, and so (shrug) there's not a lot I can do about it.
But it grates.
Ive never trusted bike shops when it comes to new bikes, I will always check them over when I get home.
Unfortunately I think OP should have told LBS that the bike was a mess when they first got it, or checked every single bolt on the whole bike.
At least he knows now not to trust the LBS again.
Ive never used a torque wrench or had anything come loose or stripped / damaged a part. Come close to it on a USE seat post, but thats their crap design rather than my skilz.
If you say something never happens, it only takes one counter example to prove you wrong.
Are you new here?
BTW I know the torque I'm using isn't that accurate, but at the very least it's going to be more consistent than me. Which is mostly why I use it. And if I need to; at least if a manufacturer asks me "Did you torque it to spec" I can honestly answer "yes" to that.
I bought a Nukeproof from a major online retailer, after 6 or 8 rides the rear chainstay bearing bolt had come loose. Maybe a Nukeproof issue?
It’s obviously wrong that a bike shop could provide something so shoddily built. Especially as there really isn’t any comeback - except shouting their name loudly all over social media and telling as many people as possible how crap they are. (maybe it won’t damage their reputation, but maybe it will remind people to check bikes they’ve had built for them!)
Usually have built my own bikes, but recently purchased off the internet from Leisure Lakes and they did a great job of setting up the bike.
Halfords are the only shop I’ve had a really bad job done by, that was a long time ago, and I know they do decent bike prep courses for staff these days (my son works for em).
Must have shifted like an absolute dog if the mech was that close to coming off
i dunno, I’ve had a mech work loose, so much so that I thought something had snapped off.
but it still shifted perfectly.
so I wouldn’t use shifting as a guide.
Deore 6100 rear mech? I've had mine come loose despite correct torquing. I suspect the thread isnt quite right on them
I never use a torque wrench on my bicycle.
I’m with you on this.
“It came lose and fell off”
“Was it done up tight enough?”
“I borrowed an old torque wrench from a friend that he got in a sale a decade ago and tightened it to spec”
“Did you try and tighten it with a multi tool?”
“No, it was tightened to the correct setting … it just came loose and fell of a mile down the road”
“So it wasn’t tight then?”
“The numbers don’t lie”
“The hand doesn’t lie”
Well if Deore is so cheap and low end surely it wouldn't cost them much to give you another?
use copaslip on the bolts when reusing old ones
😬
Copper grease is an excellent conductor and a great way to encourage galvanic corrosion. You also have to apply anti-seize correctly ie. to all contact surfaces including under the head.
Tin or zinc is seemingly better where aluminium is concerned.
Copper grease is an excellent conductor and a great way to encourage galvanic corrosion.
I have heard this before and it would seem to make sense - but I have never had a seized bolt that has been coppaslipped. I thank the great god coppaslip every time I undo one. 🙂