Dura Ace 7410 chainset BB query

[BG&E Ed]

Hi all,

I'm writing this post as incentive to sort this out:

I bought a lovely custom steel frame bike a while back and have slowly been setting it up as I want. I intend to use it for some time trials. What I have noticed is the beautiful 7410 chainset isn't symmetrical left and right. The left side is about 4-5mm further away from the centre line (from memory).

I might be answering my own question here but any confirmation would be good as I haven't dealt with older BB chainsets before: I'm guessing it probably has a bottom bracket other than the 103mm that it should have. I'll have a look when I get home to measure / see if there is any identification. I think the BB is Dura Ace of some sort.

Cheers

Ed

 

[stringfellow1946]

It should be a Dura-Ace 7410 BB 103mm

 

[BG&E Ed]

I've had a look and it has a Dura-Ace 7410 BB. With vernier callipers I have measured Left to centre 73.15 and Right to centre 69.77 so that's 3.38mm off centre. 142.92mm 'q-factor'.

 

[bm0p700f]

Chainline should be 43.5mm

 

[Midlife]

Just like to say I'm not a fan of anything other than first gen Shimano as I'm an old git but that does really look very nice, . As the BB is asymmetrical is it in the wrong way?

Shaun