Mixing sprockets from 2 cassettes

duckson

I have a 12-28 DA9000 cassette which I find ratio wise good for me, however due to the well known creaking issue I’ve swapped it for an Ultegra 6800 11-28 (no 12-28 available in Ultegra).
This is missing the 16T compared to the DA and it’s kind of noticeable!

Now if I was to buy an Ultegra 12-25 (or 11-25) could I mix and match the sprockets to make the same ratios as the DA 12-28?
So I would need to remove the 11 off the 11-28 Ultegra and add the 16T from the 12-25/11-25.

Mad_Malx

Pretty sure yes (as long as both same speed cassette). The rings don't know what others are on the block.

Edit You will have to swap the 12 too, because this is now the locking ring.

rolf_f

Mad_Malx wrote:

Pretty sure yes (as long as both same speed cassette). The rings don't know what others are on the block.[/quote]

Actually, they do - the ramping is designed to work across the block. You ideally need to keep an eye on the ramping or it may have an impact on the shifting (will have - if you think that the ramping really makes a difference!). If you are specifically buying a cassette to make this hybrid, you might want to look at the exact part number for each sprocket - it might be that both 12-23 (for example) and 12-25 have the 16 that you want but that they have the ramps in different positions and one might work better with your plans than the other.

That said, the only time I've done this was a temporary splice of an 11-25 with a 13-29. I just made the split in the middle, didn't think anything about the ramping and it seemed perfectly OK for what I needed it for (long climbs and fast descents in the alps).

Mad_Malx

^I was wondering this after I posted.
Based on my experience swapping in a 16 (on a lower groupset), it made no perceptible difference.

rolf_f

Mad_Malx wrote:

^I was wondering this after I posted.
Based on my experience swapping in a 16 (on a lower groupset), it made no perceptible difference.

You may of course have got exactly the correct sprocket for the sequence. Or ramping is mostly another brand of snake oil that does little except to shorten the lifespan of your cassette!