the 'there's no such thing as a stupid question' bike maintenance thread

John Hutton

Folks, I fitted a new front derailleur and had to break my chain in order to do so. I then reconnected the chain with the same pin. Friend of mine said to me today that I'm just begging for it to break and should replace the pin with the special one Shimano give you or if I can't locate the pin in question get a new chain.

Chain is a ten speed Shimano.

Opinions? Am I ok doing what I did? I think my mate is overreacting.

magicbastarder

if you've not got a joining pin, you could use a quick link. should only be a few euro.

John Hutton

magicbastarder wrote: »

if you've not got a joining pin, you could use a quick link. should only be a few euro.

Well I've already put it back together with pin that I took out, I had a look at that chain and now can't tell which pin I had taken out.... Should I replace the chain?

Type 17

Sorry, but your mate isn't overreacting - on 10 & 11-speed chains (and some 9-speeds), the pins are stamped to spread the ends (note the dimple in the centre of each pin-end), to prevent the link-plates from slipping off the pins.

When you push out the pin with a chain tool, you tear off the spread end-part of the pin, making it vulnerable to slipping off under heavy load if it is re-closed.
If you can find the pin you opened/re-closed, you can replace the whole link (two pins and outer plates) with a speed link, but if you can't, a new chain might be a good idea because if it snaps, you will fall off, if you're lucky - if you're less lucky you might smack your privates off the stem or top tube :eek:

John Hutton

Type 17 wrote: »

Sorry, but your mate isn't overreacting - on 10 & 11-speed chains (and some 9-speeds), the pins are stamped to spread the ends (note the dimple in the centre of each pin-end), to prevent the link-plates from slipping off the pins.

When you push out the pin with a chain tool, you tear off the spread end-part of the pin, making it vulnerable to slipping off under heavy load if it is re-closed.
If you can find the pin you opened/re-closed, you can replace the whole link (two pins and outer plates) with a speed link, but if you can't, a new chain might be a good idea because if it snaps, you will fall off, if you're lucky - if you're less lucky you might smack your privates off the stem or top tube :eek:

It's a touring bike and I'll be hauling panniers so I'll have to replace it so...

Why do so many front derailers no longer unscrew so you can slip the chain on? Annoying.


Thanks folks.

Type 17

John Hutton wrote: »

Why do so many front derailers no longer unscrew so you can slip the chain on? Annoying.

The screws used to come loose over time, which led to a different set of problems.

Mark the outside side of the old chain that you remove, and keep it - one of the pins on the outside will be missing its edge, and you'll see it if you examine each one closely...

iwillhtfu

John Hutton wrote: »

It's a touring bike and I'll be hauling panniers so I'll have to replace it so...

Why do so many front derailers no longer unscrew so you can slip the chain on? Annoying.


Thanks folks.

Just buy a quick link and when it does let go stick in the quick link. Buy a couple while you're at it they're handy to have although they usually come in packs of 2.

TychoCaine

iwillhtfu wrote: »

....when it does let go....

Yeah, but a chain letting go will usually pitch you off the bike. I've had it happen once, and it didn't end well. Fit the quick link ASAP. And if you can't find the spot, change the entire chain.

doozerie

For anyone that finds themselves scratching their heads when switching between wheels and/or cassettes of varying make or spec, this article can take the guesswork out of getting the spacers on the freehub right: LINK

Here is the summary table from the article:

John Hutton

TychoCaine wrote: »

Yeah, but a chain letting go will usually pitch you off the bike. I've had it happen once, and it didn't end well. Fit the quick link ASAP. And if you can't find the spot, change the entire chain.

Have ordered a new chain ... Live and learn!

iwillhtfu

John Hutton wrote: »

Have ordered a new chain ... Live and learn!

Put the old one on a training/turbo bike. A bit of drama about pitching you over the bars :rolleyes:

Type 17

iwillhtfu wrote: »

A bit of drama about pitching you over the bars :rolleyes:

You haven't met the people in the LBS with the busted lip and carrying the chain in their hand...

iwillhtfu

Type 17 wrote: »

You haven't met the people in the LBS with the busted lip and carrying the chain in their hand...

You probably haven't either.

Anyways I digress good luck with the new chain no harm in something new and shiny

Type 17

iwillhtfu wrote: »

You probably haven't either.

I have worked on-and-off as a mechanic in bike shops since my teens (mid-eighties), and it has happened on about two or three occasions, with many more people arriving with snapped chains, but fortunately no injuries (two or three in the last few months alone)

doozerie

Of the various things that can go wrong on a bike, I consider a snapped chain to be at the upper end of the risk range. I've had chains snap on me, fortunately I've walked (well, limped) away with nothing more than bruises but i'd consider myself as extremely lucky in that I kept the bike upright each time (which counts for a lot when it happens while you have a moving car beside you).

Personally, I take every precaution that I can with chains. Not everyone will agree with the precautions I take, but they include:
* I don't use quick links except out of necessity (e.g. I carry one in case I snap a chain while far from home). I prefer to join chains with a pin.
* If I use a quick link I don't re-use it unless it's explicitly described as reusable.
* I don't exceed the max number of newly installed pins per chain (that's 3 for a Campag chain as far as I can remember, can't recall what it is for Shimano chains, I rarely use anything other than those two brands). Amongst other things, that means not removing the chain every time I need to clean it, and not rotating chains routinely.
* I use what I consider good quality chain tools.
* I use an 11sp chain tool for 11sp chains.
* I'm very careful when sizing a new chain that I'm installing.
* I make a conscious effort to not cross-chain while riding, though it happens the very odd time when racing.
* I clean and lube my chains regularly. Even my unloved commute bike chain gets attention now and again.

saccades

A strong chain is important but my record is 7 powerlinks and who can be bothered cleaning a bike?

Macy0161

A friend of mine put herself out of action for a few months with a knee injury when a chain snapped on her out of the saddle powering up an incline. I do use quick links, and would regularly lube my chain. I did think the manufacturer's had discounted cross chaining as having any real impact though?

Internet Friend

Front derailleur seems to have collapsed this morning. It's set to be in the large chainring but is sort of stuck in between the large and small but on the small ring with the chain grinding off the derailleur. Not sure what happened but I was pushing over the canal bridge on Sheriff St at the time.

Anyone recommend a bike shop or mobile repair van that would have a look at it today (possibly being ambitious here) around Dublin 1? Probably a bad idea to try cycle it home...

magicbastarder

cycle ways, bolton cycles? give them a buzz.
there's a place on dorset street too, i forget the name.

could be a slipped cable?

Internet Friend

Sydney Cycles on NCR or Shaka Co. opposite Connolly Station seem to be the closest. Seems like it could be a slipped cable alright.

magicbastarder

if you could get an allen key and slacken off the bolt, the derailleur should drop the lower ring, which at least should get you home.
assuming it's a partially slipped cable, that is.

Internet Friend

Will have a look at it shortly and see, try get a photo of it. Shaka Co seem to offer same day repairs, even if I drop it down at lunch (from the reviews on Google anyway)

cdaly_

Internet Friend wrote: »

Front derailleur seems to have collapsed this morning. It's set to be in the large chainring but is sort of stuck in between the large and small but on the small ring with the chain grinding off the derailleur.

I've had this sort of thing happen when a cable is getting ready to break. A couple of strands break and the cable starts to unravel so the derailleur goes out of adjustment. It's pretty obvious when you look at the cable clamp at the derailleur end. If it's unravelling in the shifter, you need to sort it promptly as a snapped cable can leave damaging debris in there.

Internet Friend

Looks like the cable slipped, will drop it down to the bike shop on lunch anyway just to be sure it's not unraveling.

Internet Friend

Ok so turns out the problem is being caused by a missing cap for the bottom bracket. Must have come loose (maybe previous owner had been working on it) at some point and fallen off without me noticing. BB is a FSA MegaExo so will check with the LBS and see if they have the spares. Shaka Co don't have the parts to fix it, but they tightened screws etc on the derailleur to keep it in place for now, free of charge so that was pretty sound of them.

May just bite the bullet and switch to 105 BB and crank, both chainsets are looking a little worn at this stage. Not sure about the 26km spin home now...

magicbastarder

you mean the bottom bracket cable guide was missing?

Internet Friend

Guy in the shop described it as a dust cap, I'll know more when I go down to pick it up.

I'm presuming it's the cap that secures the cranks to the BB

Edit: added cap link. Also just read that they've a history of coming loose.

CramCycle

That explains why it wasn't in the small ring after slipping

LollipopJimmy

Internet Friend wrote: »

Ok so turns out the problem is being caused by a missing cap for the bottom bracket. Must have come loose (maybe previous owner had been working on it) at some point and fallen off without me noticing. BB is a FSA MegaExo so will check with the LBS and see if they have the spares. Shaka Co don't have the parts to fix it, but they tightened screws etc on the derailleur to keep it in place for now, free of charge so that was pretty sound of them.

May just bite the bullet and switch to 105 BB and crank, both chainsets are looking a little worn at this stage. Not sure about the 26km spin home now...

I got my Di2 through them, sound lads and I've gone in a few spins with the owner, he's actually pretty new to cycling believe it or not, he bought the business a few months ago

Internet Friend

Yeah, he seems pretty sound alright, said he's only cycling 2 years. Wasn't comfortable cycling home in case it slipped out again.

Turns out the chainset is nearing its life anyway so may as well upgrade. So considering this as it is compatible and at a decent price. Unsure on the length I should get so any advice would be appreciated.