Chain Slipping / Worth fixing up?

Moif

I've just been out on my 10+ year old Giant ATX 860 Hardtail. Didn't get very far though, as soon as I put any considerable weight down the chain slipped. I've recently replaced the chain as I neglected the bike for a while and it's been out in the rain gathering rust. But it's still in good nick bar the odd rust patch. Here's a pic of the chain on the rear cassette:



What have I done wrong? Chain too short? Not the right chain? Excuse the muck, need to give it a good clean.

I'm also wondering if it's worth fixing this bike up or accept it's had its day and buy a new one. The front wheel has a slight buckle in and the rear disc needs replacing as it's too thick plus other bits and pieces:

http://img193.imageshack.us/slideshow/w ... 1068mk.jpg

But gutted, was looking forward to a ride around town today.

Uli

Worn and dirty cassette.

Moif

Uli wrote:

Worn and dirty cassette.

That's what I thought. Looks like I should give it a bloody good clean and replace that cassette.

Chunkers1980

It won't be the dirt, it'll be the wear.

felix.london

check your jockey wheels too

Greer_

Moif wrote:

I'm also wondering if it's worth fixing this bike up or accept it's had its day and buy a new one. The front wheel has a slight buckle in and the rear disc needs replacing as it's too thick plus other bits and pieces:

You need to realign the pads - take the wheel out and push the pads back with something flat.

Moif

Nice one, cheers all.

Cassette + tools purchased. Will give the jockey wheels a look when I get underway.

mrmonkfinger

Greer_ wrote:

Moif wrote:

I'm also wondering if it's worth fixing this bike up or accept it's had its day and buy a new one. The front wheel has a slight buckle in and the rear disc needs replacing as it's too thick plus other bits and pieces:

You need to realign the pads - take the wheel out and push the pads back with something flat.

Don't push the pads.

Removed the pads first. Then push back the pistons.


This all assumes it is a hydraulic brake, not a cable brake. And, some hydraulic brakes have bite point adjustment that can be used to adjust pad clearance (so1e). Might be worth checking a manual for whatever brakes are fitted...

cooldad

I leave the pads in to push - cheaper than trashing the pistons if it goes wrong.

Moif

Hydraulics

felix.london

cooldad wrote:

I leave the pads in to push - cheaper than trashing the pistons if it goes wrong.

Especially with these new fangled ceramic ones I have now

dhobiwallah

Wheel buckle - spoke key for a few quid, a youtube video on wheel truing and 15min - 3 hrs depending how quickly you pick it up.
Basically get a water soluble whiteboard marker, and with it braced against the seat stay (or fork) slowly move it towards the rim of the spinning wheel.
It will mark the bit out of true closest to the pen.
See which spokes pull the wheel to that side of the hub and loosen half a turn, then tighten the ones either side pulling it away. (make sure you know which way to turn - I find it is the opposite way to what I feel it should be!)
Wipe the wheel clean and repeat till the pen mark is continuous.
Change sides regularly or you will end up with a perfectly straight wheel well to one side!

Brake disc won't have got thicker as it has been sat! As pads wear the pistons come further out. So if you put fresh pads in (with no wear) they need to be pushed back in. Simple way is to keep pads in, put flat bladed screwdriver between them and turn it. Will trash the pads though.

Other way is to take the pads out - use a ring spanner and lever the pistons back in; small but finite prob of trashing calipers if too heavy handed.

If bike has been sat for ages pistons might be sticky.
Without the wheel in place pump the lever till the pads come out - drop some brake fluid on the pistons - and poss clean round them with cotton bud (depends on the brake - shimano mineral oil and DOT 4 fluid most def not compatible!) and push back in.
Repeat till pistons come out freely.
If one side is jammed you may have to sacrifice a pad (on the good side) and wedge it into the caliper with something like a spanner till the hydraulic force pops the stuck pad further out and continue as above.

Can't see the pics as in China at the moment (images blocked) but if the chain was worn enough to warrant replacement the cassette may well have been too. Look at pics of a new one and compare the teeth. A worn one will have markedly lopsided teeth ('sharks tooth' or rolling wave effect)

Moif

Right well,

New cassette and it's still slipping. Not as much as before but it's still slipping. Could it be that I bought the wrong chain? Perhaps I removed too many links? It's a Clarks from Halfords if that makes any difference. Here's how things look now:









Thinking now it might be a job for the LBS but my mate has a Marin Palisades Trail he's flogging for £100 that I'm seriously considering.

I only want to get on my bike

dhobiwallah

Chain too short won't cause it to slip (but will cause other issues, such as snapping when you put it in a gear combo it now won't get round).
Chain too long might cause it to slip at the dérailleur can't take up the slack and it is flapping about.

Is it an issue in all gear combos, front and back?
Are your gears properly indexed? If they are not you may well be sat 'mid-shift' as it were and the chain will jump.
Could be a bent rear mech hanger.
Could be knackered old cables are not allowing the mech to fully return as the tension is released due excessive friction and this is causing the mech to sit 'between gears'

Knowing which gears are causing the issues will help diagnosis (ie which ring up front and which to the rear). It could be something as simple as it slipping in the small/small cogs as the chain is too long.
Does it only happen after you have shifted up the gears to a smaller rear cog?

And ref the chain, as long as it is rated for the correct number of gears at the rear (ie 9 speed) the make is irrelevant. \the difference is in the width of the chain due to the number of sprockets squeezed into different speed cassettes...

felix.london

Like I said at the beginning...check your jockey wheels :roll: From the (blury) photos they look like sharks teeth. Buy some new ones and your slippin will be stoppin

Moif

felix.london wrote:

Like I said at the beginning...check your jockey wheels :roll: From the (blury) photos they look like sharks teeth. Buy some new ones and your slippin will be stoppin

Ah yes. Sorry, missed that one.

Chunkers1980

They look fine to me.

felix.london

Sorry - this is the only picture I could find so not very clear but those jockey wheels were giving me the problems you are now having;



Spent £15 on a new set from CRC and everything working perfectly now

Moif

Ta,

Popping down to the LBS a little later on and might consider a new crank set as well as the jockeys.

Moif

Haha, problem solved. Well, problem found. Yet to go and buy replacement crank but check these out:







That'll teach me to take better care of my bike.

supersonic

They are supposed to be like that ;-)

Many teeth are shorter or profiled to help shifting. If they were worn, they'd all be worn the same amount. That said there is a little wear, but not too bad.

Moif

I have learnt this along with many other things over the past couple of weeks:

1. I am impatient. I cannot wait until payday - much to the missus's disapproval.
2. Use the right tool for the job. Especially when it comes to bottom brackets. I've spent about £50 tools over the past week or so. I see it as an investment.
3. Front derallieurs are a pain in the arse. I've f*cked up a new £26 Shimano last night by adjusting the H/L screws too much with the gear cable too tight, they barely make any difference at all now. Still, live and learn.
4. Read guides and watch Youtube. Parktools is the place to be.
5. If in doubt, ring the LBS. Evans + Halfords haven't a clue.

Got a long way to go yet: gears won't downshift to the smaller front chainwheel, I need a new rear mech, new brakes, new tyres but the bike is finally in a place where I can ride it out. to a degree

It's not like back in the day when I could build a chopper out of random bits. I can safely say I'm hooked though and I'm already thinking about build a bike from scratch. I think I'm going to find a bike workshop somewhere and take the time to learn basic bike mechanics first though

Moif

I have also learnt that exercise bikes make great MTB repair stands