Cassette Sprockets Mix & Match

[Tomba]

Might be a daft question but thought I'd ask.

I was looking for the new Shimano Sora 9 speed 11-30 cassette but they're 'unavailable' or I'm looking in the wrong places.

Anyway, at the moment I have Sram 11-32 cassette that has 11-12-14-16-18-21-24-28-32

I've seen the Sram 11-34 that has 11-13-15-17-20-23-26-30-34.

Could I take off the 34 from this and replace it with say the 12 or 14 from the 11-32?

 

[black'n'yellow]

not sure about Sora specifically, but the top 3 or 4 sprockets on Sram & Shimano cassettes are usually fixed on a carrier, so cannot be changed individually..

 

[fossyant]

Provided you can separate the sprockets and there aren't any sprockets that need to be in a particular order, then yes. You can with Shimano 8 speed.

If this is on a mtb or hybrid, just use the new cassette, wouldn't bother messing with the sprockets as the jumps on those are huge.

 

[Tomba]

not sure about Sora specifically, but the top 3 or 4 sprockets on Sram & Shimano cassettes are usually fixed on a carrier, so cannot be changed individually..

The Sram cassette I have is held together by a long narrow hex bolt (1.5mm or something).The 11 and 12 are independent of the cassette and are held in place by the lock ring.

 

[Tomba]

Provided you can separate the sprockets and there aren't any sprockets that need to be in a particular order, then yes. You can with Shimano 8 speed.

If this is on a mtb or hybrid, just use the new cassette, wouldn't bother messing with the sprockets as the jumps on those are huge.

Its for a road bike. The rear mech is a 105 5700 so using the 11-34 wont work.

 

[fossyant]

If you can pull the SRAM cassette to bits you already have, and buy the same model, then you will be ok. SRAM and Shimano do cassettes that can't come to bits, or only in parts.

Thought about getting a Shimano cassette that has the right sprockets.

 

[RecordAceFromNew]

Generally speaking the lower series cassettes are less likely to have spiders. In the case of sram, for your purpose, I believe PC 970 and lower would suit. See this.

I mix and match cogs from cassettes and have never noticed any reduction in shift crispness due to differences in shaped ramp positions, but generally one should watch out for potentially different spacer and cog thickness within / between some cassettes.

 

[Tomba]

If you can pull the SRAM cassette to bits you already have, and buy the same model, then you will be ok. SRAM and Shimano do cassettes that can't come to bits, or only in parts.

Thought about getting a Shimano cassette that has the right sprockets.

Ideally it would be the new Sora 9 speed 11-30 but you cant buy them. Or rather everywhere I've tried dont have them even though they were 'supposed' to be out this month.

I've tried contacting Shimano twice without any reply

 

[Tomba]

Generally speaking the lower series cassettes are less likely to have spiders. In the case of sram, for your purpose, I believe PC 970 and lower would suit. See this.

I mix and match cogs from cassettes and have never noticed any reduction in shift crispness due to differences in shaped ramp positions, but generally one should watch out for potentially different spacer and cog thickness within / between some cassettes.

It was the 950 series I was looking at so I should be good?

 

[PpPete]

Its for a road bike. The rear mech is a 105 5700 so using the 11-34 wont work.

You might get away with it...
My RD-6500 will cope with 11-32 and a 50-38-26 front (so massively outside Shimano's ratings)
I usually run a 9 speed 12-30 cassette cobbled together from sprockets taken from HG-50 11-32 and 11-34 cassettes, works fine, and the gaps are OK for me, but I did once try an 11-32 just to see if it would cope with the range.