Chain line - Dura Ace 7900

farrina

Hello all,

Currently running DA 7900 throughout (with DA 7900 hubs on Mavic CXP 36 DT DB stainless). Frame is a bespoke Reynolds 853 with cast vertical dropouts and standard 130 width. Cassette is DA 12/23

Overall very happy but I am wondering whether it might be possible to "tweak" the chain line slightly by either adding an additional (or replacement wider) spacer between the cassette body and the hub, the net effect if which will move the cassette body closer to the seat stay.

I believe there is sufficient space to avoid the chain binding the seat stay (I suppose at a push I could adjust "off" the 12 sprocket which I only use once in a blue moon going down a cliff face).

My main concern is that I might either damage the hub body/cassette because of the additional spacer/poor alignment or the locking ring will have insufficient area to adequately bite.

Just wondering if anyone has tried this and if so any recommendations?

Cheers

Alan

NewTTer

I dont quite understand what you are trying to achieve here, your chainline will vary across the range of the cassette depending on which gear you are in, or are you wanting to set an optimum for a favoured ratio on the cassette?

farrina

When looking at the cassette from the rear the chain line when the chain is on the 5/6 sprocket is not far out (I suppose it depends on whether its on the outer or inner front chain rings.

Your interpretation is pretty spot on - as I spend most of my time on the top half of the cassette (but on the outer chainring)I am just looking to adjust the chain line marginally so that the angle is not so acute.

I should add that I dont use the top two rear sprockets when using the outer chainring .... and vice versa when using the inner.

Just wanted to make sure I was not missing something in considering adding a wider spacer (or using two)

Cheers

Alan