Best cassette for a compact double (hill climber)

[Paul Palombo]

I am currently in the process of building (via my LBS), my first lightweight tourer/audax bike (kinesis 4s frame, ultegra compact double & group set,mavic open pro custom wheels, tubus rack, full guards etc.

Just wanted opinions on cassette, taking into account that I still light tour with circa 6kg on the rack and with hills in mind.

I was thinking 11-28 gives me the best balance between climbing ability and on flat cadence - what does everybody think, or have experience of ?

 

[RebornBumbler]

I'd suggest starting with 12 rather than 11, and go up to 30 or 32 for a tourer (assuming you've got a 50 large ring).
At normal cadences it's only a few mile per hour difference.
You'll need to check what your rear derailleur can handle though.

I only ever get into 50/11 while blasting downhill, and arguably would be better off working on my tuck!

This site is probably more use than most for figuring out what you need (you can put your own sprocket values in for the speed at cadence / cadence at speed tables): http://www.bikecalc.com/gear_ratios

 

[Kies]

I changed my stock cassette recently from 11-28 to a 12-30 (compact double) and the difference has been amazing. I now have a far better range of gears

 

[slowmotion]

If you have 50/34 chainrings, I would start at 13 and go as high as you can, say 32. Personally, I'm not worried about spinning out due to lack of high gears. Fear sets in before that problem arises. It's the lack of low gears that defeat me.

 

[Albert]

I have Compact and 11-34 cassette on all my bikes, which leaves a pretty low gear for those 15%+ hills that come along every few miles here in the Welsh hills. I have one bike using 105 front and long cage back. Another has Ultegra + 9 speed LX rear mech. Another with 105 + 9 speed Deore rear mech. All work perfectly without fuss. My Giant Revolt came standard with 48/34 front and 11.34 rear using non-series (Tiagra level) mechanicals.

 

[slowmotion]

I have Compact and 11-34 cassette on all my bikes, which leaves a pretty low gear for those 15%+ hills that come along every few miles here in the Welsh hills. I have one bike using 105 front and long cage back. Another has Ultegra + 9 speed LX rear mech. Another with 105 + 9 speed Deore rear mech. All work perfectly without fuss. My Giant Revolt came standard with 48/34 front and 11.34 rear using non-series (Tiagra level) mechanicals.

That's really handy information Albert. I didn't realise you could "mix n match" to that extent. I have always been interested in how far you could break the rules that Shimano and others lay down in their techdocs.

 

[youngoldbloke]

If its 6800 11 speed Ultegra you can fit 11-32, (11-12-13-14-16-18-20-22-25-28-32) with a GS mech. (officially ).

 

[normgow]

Have you tried fitting a smaller outer chainring ? If Shimano is not available try T.A or FSA. Check the mounting hole distance.

 

[djb1971]

There's nothing that's made me get off and walk yet using a compact with a 12-30, that's fully loaded too up very steep stuff.

There has however been times when I wish I'd got a 32.

 

[youngoldbloke]

Have you tried fitting a smaller outer chainring ? If Shimano is not available try T.A or FSA. Check the mounting hole distance.

If it is current (4 spoke) Ultegra I don't think you'll be able to fit TA or FSA. Wouldn't add anything to climbing capacity anyway.

 

[RebornBumbler]

If it is current (4 spoke) Ultegra I don't think you'll be able to fit TA or FSA. Wouldn't add anything to climbing capacity anyway.

Agreed, and a cassette is invariably cheaper than a chainring anyway.

 

[Andrew Br]

I'm using a 12-32 cassette on my audax bike and I find that it's covered all of my needs so far; I've not had to walk any hill on which I could maintain traction, even after 150+km.
I did manage to get up Mow Cop with the original 11-25 cassette but it wasn't pretty and I soon went to a 29 and then the 32.
I'm using a long-cage Ultegra RD with a Shiftmate to accommodate my Campag shifters.
It's all 10 speed and the front rings are (Campag) 50/34.

Go low; your knees will thank you for it.

ETA: On a long ride, I reckon that I'll be faster later on if I stop pedalling at 25+mph downhill and tuck so that my chin is just above the stem; the break does my legs good.

.

 

[slowmotion]

I love these "mongrel" gear set-ups! Tell me more.

 

[Andrew Br]

I love these "mongrel" gear set-ups! Tell me more.

Not much to say.
I've got 10 speed Veloce shifters, a long-cage 10 speed Ultegra RD and a SRAM 12-32 cassette with Shiftmate #3 doing the translation.
It works well.
If you're able to zoom in on the picture (the latest fark-ups improvements to Flickr are preventing me) you can see the Shiftmate at the end of the cable going into the RD.

13-12-20 Take a time to ride..... Dirty Boots are on- hi di ho...... I got some dirty boots - yeah dirty boots...... I got some dirty boots - baby by Chocolatebike1, on Flickr

My newest bike has 11 speed Chorus shifters controlling an SLX triple chainset, an XT FD and a 9-speed XT RD.
This arrangement is used by the Moulton crowd and it doesn't need a Shiftmate.
I switched to a closer-ratio cassette but the MTB chainset still gives incredibly low gearing:-

14-01-18 New Enigma RHS by Chocolatebike1, on Flickr

.

 

[slowmotion]

^^^^^^ Fantastic stuff Andrew Br! I had seen a mention of the Shiftmate a while back but just thought it to be a gimmick. To see one on a working bike of immaculate cleanliness was a joy.
Thank you.