Ultegra Di2 with 9-speed cassette

Discuss light weight issues concerning road bikes & parts.
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Posts: 46
Joined: Mon Dec 31, 2012 5:27 am

by freeloader


as noted in here -
http://www.bikerumor.com/2012/11/28/hac ... -cassette/" onclick="window.open(this.href);return false;
"stuck a 9-speed cassette on there and was able to use their micro adjust feature on the Di2 to get it shifting perfectly"

i wonder how that can be achieved? As indicated -

http://sheldonbrown.com/cribsheet-spacing.html" onclick="window.open(this.href);return false;

, the center-to-center spacing is 4.34mm and 3.95mm for 9-speed and 10-speed cassettes respectively. Assuming the

derailleur is perfectly adjusted at the 5th cog on a 9-speed cassette, it would at least be mis-aligned 0.39mm at the closest cogs and 1.56mm at the furthest cogs.

by Weenie

Posts: 45
Joined: Sun Apr 22, 2012 8:23 pm

by Chello

This would be a cool thing to see in person. I'm a little skeptical how "perfectly" this really was shifting.

Using micro adjust doesn't change the fact that the derailleur will only move in 10 speed spacing increments. I would think that at some point on the 9 speed cassette the adjustment would have to be slightly off, even if adjusted to the best possible position.

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by thisisatest

If his hanger was bent in slightly (unbeknownst to him), it would increase the horizontal movement of the derailleur per cog. That, and the floating upper pulley taking up a little slack, and the 10speed chain having more room between itself and the adjacent cog before making noise...

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