Chain noticeably looser after trackday

[f1nn]

Thinking about it, it's got to be normal but I thought I'd ask for opinions anyway.

So I put a D.I.D X ring chain on at the start of the year, and I've probably done around 1000 miles since, always kept a close eye on tension and it's never needed adjustment.

Done around 100 miles at an airfield riding day a couple of weeks ago, where there were mostly hard acceleration in 2nd and 3rd and every 90 seconds a straight where I was over 180mph most laps.

Just give the bike a once over not ridden it since the trackday, and the chain is noticeably looser, to a point where I will need to adjust it a little.

Now common sense tells me that this is the first time it has really had to "work hard"' so it's got warm and stretched a little, which is no big deal, All bolts, axle nuts, adjusters etc are fine, so it can't be anything else can it?

[obscene]

New chain stretching in would be my opinion. Just keep an eye on it as usual.

[WaferThinHam]

Chain stretching during a day of hard acceleration? Seems perfectly normal to me.

[battered]

Chains stretch as they wear, be it on a Honda Melody, a Raleigh SHopper or a GSXR 750. Some will wear faster than others. Fitting a ScottOiler will help. There will be a wear limit, until you get there just take up the slack with the adjusters.

Dunno about a motorbike but on my pushbike you measure 12 links. A new chain is 12.0", one that's getting ready for replacement 12 1/16" and a buggered one 12 1/8". Yes, even in 2015 bike chains are in inches. Not 25mm, but inches.

Best practice is to replace pushbike chains before they bugger the rest of the drivetrain, I suspect the same applies to one with a motor.

[WaferThinHam]

battered said:

Best practice is to replace pushbike chains before they bugger the rest of the drivetrain, I suspect the same applies to one with a motor.

Sounds like bks to me, given that the actual advice is to replace chain and sprockets as a matched set for motorcycles, as a new chain will munch worn sprockets, and vice a versa.

[tricky1962]

WaferThinHam said:

battered said:

Best practice is to replace pushbike chains before they bugger the rest of the drivetrain, I suspect the same applies to one with a motor.

Sounds like bks to me, given that the actual advice is to replace chain and sprockets as a matched set for motorcycles, as a new chain will munch worn sprockets, and vice a versa.

Everyone is entitled to their opinion, however, Battered is correct. Bicycle chains can be swapped without changing the rest of the chainset if done in time.

Sprockets unlimited don't comment on changing the sprockets at the same time but do give wear limits for the chain

Testing for wear
Chains do not stretch as such - they wear. The wear happens at the bearing surfaces between the pins and bushes and as the bushes become elongated the pins move excessively creating the effect of stretch over the length of the chain.
We are often asked how a chain can be tested for wear and as a rough guide wear of upto 1/4" per foot of chain length is acceptable and after this the chain should be replaced. Before carrying out the tests below, ideally, the chain has to be removed and washed eg. in parrafin, relubricated and laid on a flat surface. One end of the chain should be anchored and then tension can be applied at the other end by hand. A vernier gage is useful or a rigid rule can be laid next to the chain. If the chain is not removed from the bike, engage a low gear and rotate the back wheel so as to tension the upper strand of the chain and carry out the test on this tensioned upper strand of the chain.
With a new 5/8" pitch chain, 16 pitches will come to the 10" mark on a rule. The limit for wear measured over 16 pitches on a used chain of this size would measure 10.197 inches (10.098 inches for 'O' and 'X' ring chains).
In the case of a new 1/2" pitch chain, 23 pitches will measure 11.5 inches on a rule and the limit for wear over the same number of pitches would be 11.732 inches (11.650 inches for 'O' and 'X' ring chains).
For a 3/8" pitch chain, 24 pitches of a new chain will come to the 9 inch mark of the rule and the limit for wear would be 9.192 inches for 24 pitches.
It is a good idea to test several parts of the same chain because chains can wear unevenly, causing 'tight spots'. 'Tight spots' are often discovered when attempts are made to adjust a chain and as the back wheel is turned, the bottom strand of chain appears to be slack and then loose. This is an obvious indication that a chain should be replaced.

Taken from here

http://www.sprocketsunlimited.com/Chainmaintenance...

If it were me and this is what I do, get to the wear limit of the chain and the look at the sprockets to see if they are worn. If not, new chain and no more.

To answer the OP - No

[WaferThinHam]

So you'd be prepared to risk the life of your new 100 odd pound chain for the price of 20 odd pounds of sprockets?

To each their own, but everything I've ever seen and read suggests that you're meant to replace the lot together.....

Agree that bicycle chains can be changed alone, however they are dealing with slightly less power.

[battered]

The price comparison is the other way with a pushbike! An inexpensive 8spd SRAM chain or similar can come in at under £10, a rear cassette is £15-20+ and a chainset (the front end) more again, maybe £50 and considerably more for tasty stuff.

You can see why people swap out a chain at 12 1/16, I've had 2 or 3 chains per cassette like that, throwing them away every 2k miles or so. This keeps the chainset good for over 10k miles, provided it's not made of ally.

If a MC chain is £100 and sprockets £20 then like you I'd run the whole lot till it clapped then bin the lot.