Chain noise after crank swap 7800DA-6700ULT

[corexradnar]

Hi there all,

I recently swapped out a dooraahchee standard 7800 for and oolteegra compact 6700.

Front and rear derailleurs are dialed, dropped 4 links of chain, it's clean and lubed and measures "as new". It's a dooraahchee chain from my 7800 group.

The noise isn't that bad, I guess, but it is WAY louder, like I can hear the links hit the teeth regardless of the gear. Same for big and small ring. No contact on the front d.

Could there be compatibilty issues with the DA 7800 chain and ultegra 6700 rings/crank?

Any ideas are appreciated.

 

[oldbobcat]

Originally Posted by corexradnar .

Could there be compatibilty issues with the DA 7800 chain and ultegra 6700 rings/crank?

Any ideas are appreciated.

Only while shifting. 6700 and 7900 chains are asymmetrical for faster shifting.

I'm a little concerned about your chain length. Is the chain long enough to use big-big? Also, chain stretch indicators are not infallible. Can you estimate the total mileage on that DA chain?

 

[corexradnar]

Thanks Bobcat

The chain length is good for big/big and the noise is the same through all gears equally, not even the chainline angle has an effect on the sound. DA chain has very low use... less than 1500km. It's a Look 585 with Ambrosios and a 105 cassette. The 105 cassette was quiet with the DA crank and the sound is from the contact of the chain and chain ring.

I though it may be just a sound difference as the 6700 Ultegra has "hollow" chanirings that reach right down to the spider vs the DA 7800 that is "see through" with windows. Maybe there is a slight wear difference beyond the metrics of a stretch indicator that will break in with time. I just love a quiet drive chain so the tips are appreciated.

 

[oldbobcat]

I though it may be just a sound difference as the 6700 Ultegra has "hollow" chanirings that reach right down to the spider vs the DA 7800 that is "see through" with windows. Maybe there is a slight wear difference beyond the metrics of a stretch indicator that will break in with time. I just love a quiet drive chain so the tips are appreciated.

I'll have to listen more carefully the next time I set up a bike with Ultegra cranks. These do sound different, but I never thought of it as particularly loud.