Chain skipping/banging under load

guvnor299

Hi,

Can anyone suggest a cure to my issue.

In short, I have just replaced both my 105 cassette and chain, first ride out today but when applying pressure under load in the big ring there appears to be chain slip/loud bang.

The chain and cassette had done 5,000km so perhaps should have been changed sooner.

I’m thinking that maybe my big ring is worn?

Thanks for any help

redvision

Did you measure the chain against the old one before you put it on?
If not then that's the issue - the chain is too long.

Chain rings should last longer than 5000km.

guvnor299

Yeh, I lined them up side by side, counting the number of links the old chain had (111) and split the new one to have the same 111.

guvnor299

I’m running 50/34 plus a 11-32 cassette

thecycleclinic

Those rings dont look too worn. The skipping can be a stiff link. I dont like guessing much. I am visual person.

lincolndave

Have you used a quick link on the chain?, if so is it on the right way

guvnor299

Yes, i have checked and it appears to be on correctly

guvnor299

upon closer inspection i see the 'shimano' name is upside down - does this suggest this plate needs to be on the other side of the chain?

pblakeney

It’ll be correct when rotated to the non drive lower section. 😉

This is actually the case with Connex. When on the lower section the curve should smile. If it frowns then it is the wrong way round. In summary, maybe.

bondurant

How many miles has the big ring done?

guvnor299

About 5,000km

guvnor299

I'll take it off, use a new one but this time on the correct side

pblakeney said:

It’ll be correct when rotated to the non drive lower section. 😉

This is actually the case with Connex. When on the lower section the curve should smile. If it frowns then it is the wrong way round. In summary, maybe.

Darius_Jedburgh

I'd say big ring is worn. It is ceratinly more worn than the new chain & cassette. I sh@gged the full drive train last winter in less then 3,000 miles riding through constant grit and other detritus. When riding in winter then they all wear at an alarming rate.

thecycleclinic

My wet bike has 20000km or more on the original rings. The rings dont look worn enough to go out and buy a new ring unless everything else has been eliminated.

guvnor299

Thanks, I was thinking similar that the chain set would last more than 5000km.

I’m going to take the chain off and replace the quick link this time ensuring it’s put on the correct way!

thecycleclinic said:

My wet bike has 20000km or more on the original rings. The rings dont look worn enough to go out and buy a new ring unless everything else has been eliminated.

david7m

Looks worn to me. How does the teeth profile compare to the smaller ring?

pilot_pete

Is the cassette tight? Did you re-adjust the rear derailleur after replacing the cassette? Is the B tension correct? Are you sure the hanger is completely straight (I mean check with the correct tool, not just eyeball it)? Does it ‘skip and bang’ in every gear or just certain gears? Does it do it ONLY when in the big ring in certain/ all rear combos, or on the small front ring too? Have you checked the new chain to ensure there are no stiff links (including your chain link)? Is the chain directional? If so did you put it on the right way round? Same for the quick link?

I reckon one of the above items is probably your issue as that front ring doesn’t look that worn to me.

PP

david37

Front ring looks ok to me (though check for any damaged teeth or burrs / bent teeth and file or correct)

fenix

My winter bike has way more wear than that and it's no problem. There's nothing wrong with that chainring.

guvnor299

I had another 105 chain wheel from another bike that has done around 3000km, duly swapped them over and the problem has gone! Thanks all 😎😎😎😎

pblakeney

guvnor299 said:

I had another 105 chain wheel from another bike that has done around 3000km, duly swapped them over and the problem has gone! Thanks all 😎😎😎😎

Not found the solution though. Happy to bin a new chain without finding out why?

guvnor299

I'm still using the new chain, this time correctly attached. After a test ride i was still experiencing the skipping so changed chainset and the skipping has gone therefore i can only assume the large chain ring was the issue ;p

pblakeney said:

guvnor299 said:

I had another 105 chain wheel from another bike that has done around 3000km, duly swapped them over and the problem has gone! Thanks all 😎😎😎😎

Not found the solution though. Happy to bin a new chain without finding out why?

pblakeney

That’ll teach me to read correctly. I thought you’d changed the chain. Carry on....