Spline change on Dura Ace wheels?

Mark1962a
Mark1962a Posts: 47
edited February 2009 in Workshop
I have a set of Dura ace 7801 wheels and a set of Mavic Aksiums wheels (standard Shimano spline) and it is frustrating that the Dura wheels will only accept a Dura Ace cassette as the splines on the hub are unique & slightly higher halfway down than normal Shimano splines. I have a 12 -25 Dura Ace cassette on the 7801s and also an 11 - 28 SRAM cassette on the Aksiums and it would be nice to use the 11 - 28 on the Dura Ace Wheels or on a set of Ultegra Wheels that have just been given to me (I was amazed the Ultegra wheels used the same unique Dura Ace spline and would not take a SRAM cassette ).

Is it possibe to replace the Hub spline without changing the whole Hub? i am quite handy and do all my own work having built bikes from scratch and was keen to know if anyone could help - the expensive option is to buy a new Dura ace 7900 cassette as they now produce an 11 - 28 although they probably have a unique spline on that!!

In case u r wondering at nearly 50 yrs old i find an 11 - 28 damn handy with a compact for the North Downs

I look forward to hearing from the advanced techies out there - cheers
2009 S Works SL2
2009 Specialized Tarmac Expert
2007 Specialized Tarmac - Single Speed conversion!
2010 Specialized Rockhopper SL Expert MTB
2009 Specialized P2 All Mountain
All in need of a Bigger Garage............

Comments

  • andy_wrx
    andy_wrx Posts: 3,396
    I think what you're describing is not DA, so much as 'Shimano 10speed only'

    See Sheldon http://www.sheldonbrown.com/k7.html#10cassettes

    Shimano 8, 9, 10sp all have the same spline pattern, so if you have a Shimano 8/9/10sp steel freehub, it'll take a 8sp, 9sp or 10sp cassette (10sp cassette needs a spacer washer, but that's all).

    But your DA freehub is aluminium, so rather than having the cassette dig into the weaker splines on it, Shimano increased the height of the splines and the corresponding groove on the cassette and made it 'Shimano 10speed only'.

    Thus your 10sp cassette with its deeper grooves will fit onto a a Shimano 8/9/10sp steel hub with it's shallower splines no problem

    - but a 8sp or 9sp Shimano cassette won't fit onto your freehub as it's grooves aren't deep enough for your freehub's splines.

    This applies to your DA rfeehub and also to those 10sp Ultegra freehubs with an alu freehub body - but not those with a steel freehub body.

    SRAM cassettes/hubs use the same Shimano spline pattern - but looks like even in 10sp they have the same spline depth, hence a SRAM 10sp cassette won't fit your freehub.

    You don't need a DA cassette as such, you just need a Shimano 10sp cassette, so you can use DA, Ultegra or 105
    - I don't think you can get 11-28, that's SRAM only, but you can get 12-27 in 105 & Ultegra