Dulwich Hill Bicycle Club

Well I bought this TT bike and it's got 10 speed SRAM Apex on it. And I'm a Shimano Ultegra woman. With Di2 on one bike and manual on the other.

The bike came with 2 rear wheels, a Zipp disc and a training wheel without a cluster.

So - in the interests of interchangeability of wheels, what sort of cluster should I put on this training wheel?

Brainstrust: can I put an Ultegra 6700 cluster on it? Or do I have to get a SRAM PG1070 one?

SRAM 9 speed and 10 speed cassettes are compatible with the equivalent Shimano.
Note: The shifters/rear derailleurs are not

Any shimano 10 speed cluster will work fine with the Apex gearing. Depending on the wheel/hub you may need a 1mm spacer to go behind the ultegra cassette, but that comes as standard with the cassette anyone so its not really an issue.

Thanks both.

How would I know if I need the spacer? Would it just not fit without it?

Thanks both.

How would I know if I need the spacer? Would it just not fit without it?

if the cassette doesn't spin on the freehub you need the spacer. I discovered this AFTER changing the cassette, tightening up the lockring and refitting the wheel. note to self, spin the cassette on the free hub first.

Here's a good online tool for looking at compatibility issues
http://www.drivetraincalculator.com/drivetrain.php?