How do I know I need a new chain?

[ec1 eex]

When I had my bike MOT'd last year, the guys there told me that I'd be needing a new chain very soon. I asked them how much life was left in the one I've got and they told me maybe 1,000 miles. My bike (Bandit 600) is now 1,000 miles later at 8,000 miles on the clock (3.5 years old) and I'm thinking "do I really need a new chain or were they just looking for some additional work to tack onto the bill?"

Obviously the last thing I'd ever want is for the chain to snap, and I appreciate the 8,000 miles may be a lower mileage than many would expect to change a chain at. Nearly all of those miles have been in central London where I'm always accelerating or braking with very little maintaing speed. Admitedly I am crap at oiling the chain, but it does get oiled now and again (maybe every 3 months).

Also I remember reading that if you're getting a new chain, you should also be getting new sprockets. Is that true?

Thanks, Phil

[randlemarcus]

Personal experience from this last week is that you know you need a new chain when the slack reappears too fast. Got back from LeMans, and had just over 3/4 inch slack, so booked it in for a new chain and sprockets as I'd had it adjusted before I left (might just have been working it quite hard over in France)

Riding it into the shop on Monday, lose all motive power, and bingo - the chain has snapped. Bu99er. One AA ride and a few days late, we have the bike back, new chain, new sprockets front and back, but the engine is now missing a small rim of metal used to hold a plastic sprocket cover on. Not essential, but could just have easily been the petrol tank or the crankcase. You do NOT want the chain snapping at any speed - I was doing about 10mph at the time.

The sprocket thing is purely and simply preventative maintenance - it makes sense to change the lot at once, to ensure that a new chain isnt knackered by uneven teeth on an old sprocket and vice versa.

[Vitesse39]

Firstly if you run out of adjustment room on the swing arm will tell you.
If you have a Haynes or workshop manual it will tell you how to measure if the chain has streched more than manufacturers spec in any one place
you dangle a weight (dunno how much weight) on the bottom of the chain, and measure 'X many' links on the top. Do this in a number of places, longest/worst measurment is the one to concern yourself with.

Chain lubing - personally I lube my chain every week (350 miles), this maybe OTT but it does sound much quieter after the lube each week

Defo change sprockets and chain together, an old sprocket can knacker a new chain in no time.

[dern]

ec1 eex said:

When I had my bike MOT'd last year, the guys there told me that I'd be needing a new chain very soon. I asked them how much life was left in the one I've got and they told me maybe 1,000 miles. My bike (Bandit 600) is now 1,000 miles later at 8,000 miles on the clock (3.5 years old) and I'm thinking "do I really need a new chain or were they just looking for some additional work to tack onto the bill?"

Get your haynes manual or workshop manual out and adjust the chain so the slack is correct and then see if the marks on the swing arm take you outside the service length of the chain.

You should be doing this on a regular basis and not relying on mots and services to do it.

[crankedup]

If oiling your chain is a pain in the bum get a Scottoiler fitted and extend your chain life (and sprockets) at least x3. From personal experience they are brilliant bits of kit.

[ec1 eex]

Thanks for the advice all. I'd actually forgotten I had a Haynes manual (last looked at it 3 years ago)

What kind of bill should I expect for chain & sprockets should it turn out I do need a new chain?

[Vitesse39]

For an Xring chain and Sprockets about £100 plus an hours labour maybe only 0.5 hour labour as it's naked, £150 total at worst i would think

[crankedup]

Use paraffin to clean up the chain before using the chain lube, beats the pants off all those fancy cleaners IMHO.

[Vitesse39]

Parafin worked a treat for me too

[EvoBarry]

An quick check for a prematurely knacked chain, apart from the having to adjust it more often obviously, is to get hold of a link with your fingers (on the back sprocket) and try to pull it away from the back of sprocket - if it can be pulled away signifcantly then its knacked.

[chrissarjeant]

Even if your not sure if its at the point of having to change it I would change it anyway I learn't the hard way when my chain snapped causing broken hugger,undertray,sprocket cover lower engine casing and denting the swing arm ,Also it nearly took my mates head off as he was riding behind.But I still think I was lucky as it could have got wrapped around the wheel and thrown me off.

[MrsMiggins]

You should change the sprockets when you change the chain. Have a look at the sprockets on the bike now, you'll probably find that the teeth have developed a hooked appearance as they've worn. If you just replace the chain the worn sprockets will cause it to wear more quickly.

I second the Scottoiler idea. I've got a touring one fitted on my bike and it's the biz!

[iguana]

On a bandit ignore the swing arm marks & measure with a ruler, far more accurate.

With a scottoiler & additional occasional can lube yr chain will- even if bike is ridden v v hard, last an easy double amount longer than 8k miles too.