[chequebookracer]

Having seen some similar threads on here I decided for my new bike I'd go down the cut down cassette route.

So I bought a PG970 11-34 for £20 off CRC, didn't seem worth spending more as I would cut off the alloy carrier hung sprockets anyway. Then I weighed it, 449grams, bit chunky!!! I then took the cassette apart and ground down the two biggest cogs to just spacers to leave me a 7spd 11-26, painted the cut bits with hammerite and weighed it, 252grams.

So still heavier than a SLX 9 speed 11-28 but a bit cheaper!

Not sure if it was worth it really, gives me a good spread of gears and should reduce those moments desperately trying to grab 2 or 3 changes at a time but hasn't really worked out weight wise and stops me using cheap Shimano road mechs due to the angle of the cassette (i.e. it was an 11-34). Can't bring myself to spend £90 on a Saint so either medium cage SLX or defect to sram and buy a new shifter.

Anyway thought this was worth posting incase somebody else was thinking over the options.

 

[chequebookracer]

Lol. I might see if I use the 26t and then go to a 11-23t 6 speed (pretty sure the 26t was dialled out on my old cassette because I once had a very expensive mech in the spokes incident) but still can't see it making sub 200g.

Are the smaller Dura ace sprockets made from ti?

 

[- seb]

(sorry, deleted my post to put it up again with more info)

My 11-19 6-spd dura-ace is 108g

Not quite sure what it consists of, have had it on so long now. My email history shows that it was an 11-23 when I bought it....

I know I removed the 21/23 (on a separate carrier - so it was easy).

Then I'm fairly sure I replaced the 15/17 with a 16 I had lying around.

Started 11-12-13-14-15-17-19-21-23
Became 11-12-13-14-16-19 (or maybe 11-12-13-15-17-19, I forget)

Sounds about right. I believe the only ti cogs are the 21/23 that I removed, though the 17 & 19 might be as well, I can't remember now.

Meh - it's light, it has all the gears I need, I run my chain super tight and my shifting is as crisp as I could want. I'm happy

 

[Tomasis]

seb, can you show the "chain system".. ie whole chain incl cassette? almost 100g not bad!

I need 32-34T for various reasons, ie run cycle 10km on bad way to train station lol..I had used tiagra 25t and it was too small anyway.

I bought a 32T Sram 980 from CRC (not expensive). According to weightweenie, it weighs 275gram.

One promised to sell his a bit used XTR 34T. We'll see how I figure out to save weight through mixing between sram and xtr while having access for 32t.

Your suggestion for the setup?

 

[MinorThreat]

In reading the above, it got me to thinking:

Could you clean things up by mixing a SRAM 1:1 shifter with a 2:1 Shimano rear derailleur to make a shifting setup that would move the derailleur two cog spaces for each shift - - allowing you to eliminate every other cog in a 9-speed cassette, giving you the five speeds? In other words, take, say, an 11-34 cassette and use 11, 13, 15, 20 and 26 cogs all spaced two cogs apart (like, with aluminum washers or PVC spacers on the cassette body). Could it work?

I can imagine downshifts might be a bit notchy; but I'm thinking that wouldn't be as much of an issue as long as the upshift jumps went smooth. Am I way off-base here?

 

[no skid marks]

In reading the above, it got me to thinking:

Could you clean things up by mixing a SRAM 1:1 shifter with a 2:1 Shimano rear derailleur to make a shifting setup that would move the derailleur two cog spaces for each shift - - allowing you to eliminate every other cog in a 9-speed cassette, giving you the five speeds? In other words, take, say, an 11-34 cassette and use 11, 13, 15, 20 and 26 cogs all spaced two cogs apart (like, with aluminum washers or PVC spacers on the cassette body). Could it work?

I can imagine downshifts might be a bit notchy; but I'm thinking that wouldn't be as much of an issue as long as the upshift jumps went smooth. Am I way off-base here?

it's not 2-1, and 1-1 but.
Good idea, but no.

 

[MinorThreat]

Yeah, I threw this out on a mechanics forum too and I guess Shimano is actually closer to 1.7:1, so there aren't true even ratios.

Best idea kicked back to me there was to shed the outer two and inner two cogs and run five of your choosing in the center of the cassette body; though I guess the limit screws can't choke it down quite that narrow.

 

[Cabdoctor]

Yeah, I threw this out on a mechanics forum too and I guess Shimano is actually closer to 1.7:1, so there aren't true even ratios.

Best idea kicked back to me there was to shed the outer two and inner two cogs and run five of your choosing in the center of the cassette body; though I guess the limit screws can't choke it down quite that narrow.

You can just go to a good hardware store or your local shop might have some longer screws hanging around.

I had an old 8spd DA derailleur that I converted to a single speed tensioner by putting in longer limit screws and locking it into the center of the cassette body. So it is definitely possible

 

[MinorThreat]

^^ Thank you. I wondered if longer limit screws would work; but not having peered closely enough to see exactly how they run into their stops, was not sure.

 

[richgardiner]

Are the 970's supposed to come with a separate carrier? I bought mine for £27 in the crc sale, think its a 11-26, and it just came as a bunch of loose, separate cogs and about 7 red spacers. Was it supposed to come with a metal carrier running through the center? Sorry for the slight hijack.

 

[- seb]

To whoever wanted photos:

I don't recommend that dura-ace rear mech though, fell apart. Have now put the older-style DA mech that I had before back on and it's still going strong.