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Change cassette/rear derailleur or go sub-compact?

Has anyone ever decided to go sub compact, say 48/30, rather than change the rear cassette? 

I have moved to hill country. My rear cassette is 12-25 and I struggle on some of the steeper ascents. I have a compact on the front.

I have a Record rear derailleur (short) that won't cope with a larger ranging cassette. Instead of changing the rear derailleur and cassette I wondered if going to a sub compact would give me the equivalent of being in the 32 teeth sprocket?

I am crap at maths and struggled to grasp the tables that work it out for you.

 

If you're new please join in and if you have questions pop them below and the forum regulars will answer as best we can.

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37 comments

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Canyon48 | 5 years ago
1 like

Has anyone else mixed and matched chainrings?

I recently moved and my commute doesn't require a 34 front with 32 rear combo (my old commute did due to super steep hills!).

I switched to 50/34 with 11-28 but found the jump between the 34 and 50 was too great (47%) so I could never find the right gear.

I've since opted for a 50/36 with 11-32 so I now have a slightly greater range of gears but with really close front chainrings, which means there's no large jump to get in the big ring.

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darrenleroy | 5 years ago
2 likes

Thanks for all the tips. I got lost when gear inches was bandied about though. I'm crap at maths.

In the end I bought a bit of a compromise option; a 16-30 10 speed rear cassette and I fitted an inner front chain ring of 33 teeth. I bought a Veloce rear mech and new chain. I was concerned the 17 tooth difference between the inner and outer chain rings would be too big but it worked fine.

This hack worked okay. It got me up The Tourmalet and the Hautacam okay. I had enough bottom end gearing to cope (just) with the 10 per cent sections. I think what I need to do is toughen the fuck up and lose some weight and ride more. 

Starting at 16 teeth leaves me struggling not to spin out going downhill. 

My conclusion is an 11-32 rear cassette and a 50/34 front ring is the right way to go for fairly fit, not overweight, once or twice-a-week cyclists.

 

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Simon E replied to darrenleroy | 5 years ago
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darrenleroy wrote:

 I think what I need to do is toughen the fuck up and lose some weight and ride more. 

You don't need to get fitter and lighter but it does make cycling up hills - and in fact any riding - more enjoyable.

IMHO it's not really about toughening up, more about having goals and then working towards them. Nice to know you found a workable solution.

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CXR94Di2 | 5 years ago
0 likes

Can you not use a road link/wolf link derailleur extender

See this thread, a chap is using 'Roadlink' with campag

http://road.cc/content/forum/221757-campagnolo-potenza-compatability

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CXR94Di2 | 5 years ago
1 like

Nobody spins out a 53t crank on the flat, even the pros, unless it's on a long steep descent.

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CXR94Di2 | 5 years ago
1 like

No issues with rubbing, first the Di2 front derailleur self trims as you move across the cassette gearing. Second, I ensured that the spacers on the bottom bracket, were spot on to give the correct alignment. I think I sanded down one spacer removing 1mm of thickness

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maviczap replied to CXR94Di2 | 5 years ago
1 like

CXR94Di2 wrote:

No issues with rubbing, first the Di2 front derailleur self trims as you move across the cassette gearing. Second, I ensured that the spacers on the bottom bracket, were spot on to give the correct alignment. I think I sanded down one spacer removing 1mm of thickness

Having read your posts properly,  I saw you're using an xtr front mech, which is very useful to know, I did wonder if it was possible.

Not sure if I can do this on my carbon Battaglin, which has a fixed mech hanger in the front, but my Ti bike does use a band on mech, so ilI' be trying your mod out for sure.

As you correctly said, it's all about getting up the climbs comfortably, rather than worry about how your bike looks or what people say.

I remember seeing someone back in 2009  ono the Tourmalet with a dinner plate rear cassette, which must have been a mountain bike cassette, as no one did big sprocket cassettes for road bikes then, he looked comfortable, so I thought why not.

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CXR94Di2 replied to maviczap | 5 years ago
1 like
maviczap wrote:

CXR94Di2 wrote:

No issues with rubbing, first the Di2 front derailleur self trims as you move across the cassette gearing. Second, I ensured that the spacers on the bottom bracket, were spot on to give the correct alignment. I think I sanded down one spacer removing 1mm of thickness

Having read your posts properly,  I saw you're using an xtr front mech, which is very useful to know, I did wonder if it was possible.

Not sure if I can do this on my carbon Battaglin, which has a fixed mech hanger in the front, but my Ti bike does use a band on mech, so ilI' be trying your mod out for sure.

As you correctly said, it's all about getting up the climbs comfortably, rather than worry about how your bike looks or what people say.

I remember seeing someone back in 2009  ono the Tourmalet with a dinner plate rear cassette, which must have been a mountain bike cassette, as no one did big sprocket cassettes for road bikes then, he looked comfortable, so I thought why not.

Check out the compatibility chart I posted. You can use XT with XTR front or rear derailleur.

What you can't do is mix road Di2 derailleurs with MTB derailleurs.

I think XTR in Di2 is the only triple front derailleur available currently.

Avatar
CXR94Di2 replied to maviczap | 5 years ago
1 like
maviczap wrote:

CXR94Di2 wrote:

No issues with rubbing, first the Di2 front derailleur self trims as you move across the cassette gearing. Second, I ensured that the spacers on the bottom bracket, were spot on to give the correct alignment. I think I sanded down one spacer removing 1mm of thickness

Having read your posts properly,  I saw you're using an xtr front mech, which is very useful to know, I did wonder if it was possible.

Not sure if I can do this on my carbon Battaglin, which has a fixed mech hanger in the front, but my Ti bike does use a band on mech, so ilI' be trying your mod out for sure.

As you correctly said, it's all about getting up the climbs comfortably, rather than worry about how your bike looks or what people say.

I remember seeing someone back in 2009  ono the Tourmalet with a dinner plate rear cassette, which must have been a mountain bike cassette, as no one did big sprocket cassettes for road bikes then, he looked comfortable, so I thought why not.

Check out the compatibility chart I posted. You can use XT with XTR front or rear derailleur.

What you can't do is mix road Di2 derailleurs with MTB derailleurs.

I think XTR in Di2 is the only triple front derailleur available currently.

Avatar
CXR94Di2 | 5 years ago
2 likes

photo XTR Di2 triple with 48/36/26 gears

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maviczap | 5 years ago
0 likes

Back on topic.

My first trip to the Pyrenees I used 9 speed triple 50/39/30 with 28 biggest. I was able to spin up the climbs, as a rider from flat East Anglia, I was able to climb better than my mates from Wales who were on compact. To be fair they were carrying more body weight than my 67kg

Next few years were on 10speed 50/34 with a 30, which I managed, but couldn't spin up like the triple.

Upgraded to 11speed and the last 2 trips, I used a 50/33 with 32, but probably due to a lack of miles ,getting older and weighing 70kg I did struggle on my last trip.

I'm back in the Pyrenees next weekend, and ilI' be using 46/32 and a 34, with more miles and weighing 67kg, so let's hope I can spin up, rather than grind up.

I'd quite happily use a triple but I'm using Di2, anyone using Di2 with a triple, and I don't mean using 2 two of the three?

I have in my parts locker, a Tiagra triple and 105 triple shifter, which will be deployed once age overtakes ability, which won't be long

Avatar
CXR94Di2 replied to maviczap | 5 years ago
0 likes

maviczap wrote:

Back on topic.

My first trip to the Pyrenees I used 9 speed triple 50/39/30 with 28 biggest. I was able to spin up the climbs, as a rider from flat East Anglia, I was able to climb better than my mates from Wales who were on compact. To be fair they were carrying more body weight than my 67kg

Next few years were on 10speed 50/34 with a 30, which I managed, but couldn't spin up like the triple.

Upgraded to 11speed and the last 2 trips, I used a 50/33 with 32, but probably due to a lack of miles ,getting older and weighing 70kg I did struggle on my last trip.

I'm back in the Pyrenees next weekend, and ilI' be using 46/32 and a 34, with more miles and weighing 67kg, so let's hope I can spin up, rather than grind up.

I'd quite happily use a triple but I'm using Di2, anyone using Di2 with a triple, and I don't mean using 2 two of the three?

I have in my parts locker, a Tiagra triple and 105 triple shifter, which will be deployed once age overtakes ability, which won't be long

I'd quite happily use a triple but I'm using Di2, anyone using Di2 with a triple, and I don't mean using 2 two of the three?

Yes yes

I built my Tripster V2 last year for mountain climbing using XT di2 groupset, initally with 40/28 crank, a 11-32 or 11-40 cassette.  I modified to get 44/28 crank to give a little more flat down hill speed.  

Ive now changed my front Di2 XT 2 gear derailleur to a XTR Di2 3 gear.  These are fully compatible with my set up.  I then fitted an XT triple crank 48/36/26. It works beautifully either in syncro mode or manual mode.

Shimano spec is that XTR will only take 40t max crank, this is rubbish as 48 fits easily.  Ive hear of 50t triple cranks being fitted with careful setup.

Having a band clamp for the front di2 derailleur is recommended so to allow fine adjustment

Here is shimano compatibility chart and a photo of my new crank with XTR di2 derailleur 

 

Avatar
CXR94Di2 replied to maviczap | 5 years ago
1 like

maviczap wrote:

Back on topic.

My first trip to the Pyrenees I used 9 speed triple 50/39/30 with 28 biggest. I was able to spin up the climbs, as a rider from flat East Anglia, I was able to climb better than my mates from Wales who were on compact. To be fair they were carrying more body weight than my 67kg

Next few years were on 10speed 50/34 with a 30, which I managed, but couldn't spin up like the triple.

Upgraded to 11speed and the last 2 trips, I used a 50/33 with 32, but probably due to a lack of miles ,getting older and weighing 70kg I did struggle on my last trip.

I'm back in the Pyrenees next weekend, and ilI' be using 46/32 and a 34, with more miles and weighing 67kg, so let's hope I can spin up, rather than grind up.

I'd quite happily use a triple but I'm using Di2, anyone using Di2 with a triple, and I don't mean using 2 two of the three?

I have in my parts locker, a Tiagra triple and 105 triple shifter, which will be deployed once age overtakes ability, which won't be long

 

The gearing you found easy for the Pyrenees was down to your weight.  Ive ridden with a variety of riders of different weights.  Light riders, sub 75kg, can get away with compact 50/34 11-28/32 setups when climbing mountains.  When heavyweight riders try mountains they need alot easier gearing, I go upto 40t cass and now a 26t chainring to be able to spin for hours.  Ive seen 90+kg riders die a horrible slow grind death using a standard compact setup.  I weigh 94kg+bike+kit so easily nudging 110kg whilst climbing. 

Ive just come back from the Alps and was able to maintain a decent cadence of 80rpm for the like s of the Glandon, Galibier and Croix de fer, These are climbs of 25+km long average 7+%

 

Note 

light riders will climb faster than heavy riders on long climbs.  Either let them go or leave 10 mins earlier to meet near the top.

I and another chap left 15 mins earlier for the Croix de fer, we were caught up within a km of the top some 30km long climb

Avatar
maviczap replied to CXR94Di2 | 5 years ago
0 likes

CXR94Di2 wrote:

maviczap wrote:

Back on topic.

My first trip to the Pyrenees I used 9 speed triple 50/39/30 with 28 biggest. I was able to spin up the climbs, as a rider from flat East Anglia, I was able to climb better than my mates from Wales who were on compact. To be fair they were carrying more body weight than my 67kg

Next few years were on 10speed 50/34 with a 30, which I managed, but couldn't spin up like the triple.

Upgraded to 11speed and the last 2 trips, I used a 50/33 with 32, but probably due to a lack of miles ,getting older and weighing 70kg I did struggle on my last trip.

I'm back in the Pyrenees next weekend, and ilI' be using 46/32 and a 34, with more miles and weighing 67kg, so let's hope I can spin up, rather than grind up.

I'd quite happily use a triple but I'm using Di2, anyone using Di2 with a triple, and I don't mean using 2 two of the three?

I have in my parts locker, a Tiagra triple and 105 triple shifter, which will be deployed once age overtakes ability, which won't be long

 

The gearing you found easy for the Pyrenees was down to your weight.  Ive ridden with a variety of riders of different weights.  Light riders, sub 75kg, can get away with compact 50/34 11-28/32 setups when climbing mountains.  When heavyweight riders try mountains they need alot easier gearing, I go upto 40t cass and now a 26t chainring to be able to spin for hours.  Ive seen 90+kg riders die a horrible slow grind death using a standard compact setup.  I weigh 94kg+bike+kit so easily nudging 110kg whilst climbing. 

Ive just come back from the Alps and was able to maintain a decent cadence of 80rpm for the like s of the Glandon, Galibier and Croix de fer, These are climbs of 25+km long average 7+%

 

Note 

light riders will climb faster than heavy riders on long climbs.  Either let them go or leave 10 mins earlier to meet near the top.

I and another chap left 15 mins earlier for the Croix de fer, we were caught up within a km of the top some 30km long climb

Yep, I get that and take my hat off to you, as you're nearly 30kg more than me. I've done all those climbs, bar Galibier the long way up the telegraph. Croix der Fer was a big test, just because of the length of the climb.

Thanks for the photo, I might experiment with my Tiagra triple. Any issues with chain rub on the front mech?

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bobinski | 5 years ago
0 likes

I changed from a 50/34 to a 48/32 with 11-28 for mountain riding. I thought close enough to a 50/34 11-28 without need to swap cassette and rear Ultegra short derailleur. It wasn’t enough and I ended up swapping in an 11-32 as well. What a huge difference. Had already ruined my legs at a cadence of 70 but now better able to spin at 75-80. No issues using short cage at all. 

The other riders were using a minimum of 50/34 and 11-32 or even 34

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CXR94Di2 | 5 years ago
3 likes

I've got a triple crank to fit 48/36/26 with Di2 when I return home. I will run either a 11-32 or 11-40 Cass. I've been using a twin crank of 44/28 in the Alps this week and has been perfect for me to sustain 80rpm all the way up climbs like the Galibier with my 94kg weight.

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BehindTheBikesheds | 5 years ago
2 likes

get a compact triple, 50/36/24, solves all your problems and you can keep the 11-25

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darrenleroy replied to BehindTheBikesheds | 5 years ago
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BehindTheBikesheds wrote:

get a compact triple, 50/36/24, solves all your problems and you can keep the 11-25

 

I'm not getting a triple. I mean, I'm not Peter Sagan cool, but I have some dignity. 

Avatar
CXR94Di2 replied to darrenleroy | 5 years ago
6 likes

darrenleroy wrote:

BehindTheBikesheds wrote:

get a compact triple, 50/36/24, solves all your problems and you can keep the 11-25

 

I'm not getting a triple. I mean, I'm not Peter Sagan cool, but I have some dignity. 

 

The word is vanity. 

 

What ever get you up the hills in the most comfortable way

Avatar
darrenleroy replied to CXR94Di2 | 5 years ago
2 likes

CXR94Di2 wrote:

darrenleroy wrote:

BehindTheBikesheds wrote:

get a compact triple, 50/36/24, solves all your problems and you can keep the 11-25

 

I'm not getting a triple. I mean, I'm not Peter Sagan cool, but I have some dignity. 

 

The word is vanity. 

 

What ever get you up the hills in the most comfortable way

 

You're quite right, it is vanity. Last summer I met a middle aged Belgian chap in Le Bourg-d'Oisans who was doing some riding, He had a triple on the back. At dinner I was sat next to a British marine and his girlfriend (ex-Wales international runner turned very keen cyclist). The marine fancied himself a bit; you know the type; buff, very focussed, very dull.
We were comparing times. When the Belgian chap told us his time the marine went quiet. The Belgian was riding a triple. He explained that it allowed him to spin at his preferred cadence whatever the incline, thus maintaining rhythm. I'm still not fitting a triple though. 

Avatar
BehindTheBikesheds replied to CXR94Di2 | 5 years ago
2 likes

CXR94Di2 wrote:

darrenleroy wrote:

BehindTheBikesheds wrote:

get a compact triple, 50/36/24, solves all your problems and you can keep the 11-25

I'm not getting a triple. I mean, I'm not Peter Sagan cool, but I have some dignity. 

The word is vanity. 

What ever get you up the hills in the most comfortable way

Absolutely, many a time I've watched pros come to a standstill and almost falling off due to running out of gears. Tour of Britain a couple of years back and suprisingly it was raining in the Lake District, watched with great hilarity as an old codger with a walking stick outpace the chasing bunch up a wet steep bit., it was comedy gold

 

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Daveyraveygravey replied to darrenleroy | 5 years ago
2 likes

darrenleroy wrote:

BehindTheBikesheds wrote:

get a compact triple, 50/36/24, solves all your problems and you can keep the 11-25

 

I'm not getting a triple. I mean, I'm not Peter Sagan cool, but I have some dignity. 

 

Good grief!  I borrowed a mate's bike that had a triple whilst my bike was being fixed, and it was great!  I used the front shifter much more than I would normally, and having that option to change 2-3 teeth's worth up and down at the front was brilliant.

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VeloUSA | 5 years ago
1 like

If you decide on a  Wolf Tooth Roadlink ensure the seller accepts returns because Wolf Tooth says

* Compatible only with Shimano 10- and 11-speed rear derailleurs

   * Not optimized for or recommended for use with other brands.

https://www.wolftoothcomponents.com/pages/roadlink-tech-page

 

 

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alotronic replied to VeloUSA | 5 years ago
0 likes

VeloUSA wrote:

If you decide on a  Wolf Tooth Roadlink ensure the seller accepts returns because Wolf Tooth says

* Compatible only with Shimano 10- and 11-speed rear derailleurs

   * Not optimized for or recommended for use with other brands.

https://www.wolftoothcomponents.com/pages/roadlink-tech-page

 

 

 

 

Sorry, missed that the OP was talking Italian - worth a search to see if they work then!

Avatar
LastBoyScout | 5 years ago
1 like

I've run 53/39 with an 11-32 cassette on a short cage Shimano Ultegra rear mech for a very hilly ride without any problems, even though it's not supposed to work - just adjusted the b-screw a bit.

I know it's not your Record kit, but have you actually tried it?

Avatar
alotronic | 5 years ago
3 likes

Cheapest way to get where you want is leave the 34/50 on the front and buy a £20 'road link' which is a thing that sits on the end of your mech hanger and pushes the rear mech further down. You can then use a 36 or even 40 as biggest sprocket on the back via a MTB cassette - gives you the same range as a subcompact with a 12-28 or 12-32. I put one on my bike for some welsh hills last week for a 34 x 36 granny gear and it worked a treat.

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maviczap replied to alotronic | 5 years ago
2 likes

alotronic wrote:

Cheapest way to get where you want is leave the 34/50 on the front and buy a £20 'road link' which is a thing that sits on the end of your mech hanger and pushes the rear mech further down. You can then use a 36 or even 40 as biggest sprocket on the back via a MTB cassette - gives you the same range as a subcompact with a 12-28 or 12-32. I put one on my bike for some welsh hills last week for a 34 x 36 granny gear and it worked a treat.

This ⬆⬆⬆⬆⬆⬆⬆⬆⬆⬆

I'm running  praxis works 46/32 chainrings on the front, and my Ultegra GS cage just about managed to run a SRAM 36t largest sprocket without a roadlink. With a roadlink copy installed, then no problem running a 36.

You can find these roadlink things on a well known auction site. The original roadlink things are overpriced for what they are, but cheaper than a new rear mech.

 

Avatar
TypeVertigo | 5 years ago
0 likes

BikeCalc is an excellent tool for this.

Assuming you run a 700C x 28 mm tire:

Your current 12-25 x 50/34 drivetrain has a range of 36.30-111.31 gear inches

A 12-25 x 48/32 drivetrain will give you a range of 34.17-106.77 gear inches

An 11-32 x 50/34 drivetrain will give you a range of 28.29-121.45 gear inches

 

Going wider on the cassette yields more range both ways. You'll have an easier climbing gear and a harder top gear/higher theoretical top speed

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herrkaa | 5 years ago
1 like

I have a Chorus with a short cage and I've been running a 12-29 Miche cassette for years without any issues. Are you quite sure that your Record won't cope?

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darrenleroy replied to herrkaa | 5 years ago
0 likes

herrkaa wrote:

I have a Chorus with a short cage and I've been running a 12-29 Miche cassette for years without any issues. Are you quite sure that your Record won't cope?

 

I'm not 100 per cent sure but my LBS has said it won't. It's quite a jump from 25 to 29. My rear derailleur is already pretty stretched out in the 25 cog.

I'm thinking I will have to replace the rear derailleur and cassette. Bummer. I might just go the whole hog and change up for an 11 speed Potenza. I hate wasting equipment that works perfectly but I suppose I could try and flog it on eBay. 

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