Bicycle Mechanics - need lower gearing for shimano 10sp

I reside @ sealevel with flater terrain, but am planning a weeklong ride in colorado. I currently have a compact double 50/34 and 11-28 cassette. I did a similar ride last year and have some difficulty in the high elevation and steeper areas. I'd like to do the ride this year without struggling, but also keep the cost of components under control

I feel a 30t cassette would help a lot, but I'm unsure if it would work with a short cage ultegra 6700 RD. The 28t worked fine last year. If this would work, where could this be purchased

Another option is a mountain 2x9 crank or maybe even a triple mtn or road crank. It seems I could use the outer 2 chainring on the mtn crank or inner 2 for the road and just reuse the 28t cassette from last year. For the mountain, would I just have to lower the FD?

I'm open to any ideas.

As a general rule mountain cranksets don't work well with road shifters and front derailleurs. You may be able to get it done if your seat tube is uniformly round and if your front derailleur is a clamp-on type.
It would be possible to replace the cassette with an IRD 10-speed mountain cassette and a Shimano mountain type rear derailleur.
Your current low gear, 34/28 is pretty low, and there are no gears that will add oxygen to those higher elevations. If possible training in some hills or mountains before your trip to Colorado would help.

I think a lot of your trouble comes from the different biomechanics of riding uphill vs. on level ground. We tend to sit back, drive the heel, and use the hip extensors more.

If you have a trainer, try elevating the front wheel.

I was in pretty good shape here in IL, and went back to Boulder for a week. At first, I felt like garbage on the hills, but after the 2nd day I was good to go. Some mechanical adaptation, some ventilatory adaptation to altitude, and you're good to go.

SRAM is now selling an 11-32 10speed cassette (PG-1050) that should have spacing compatible with shimano. However I don't think a short cage derailleur will work.

IRD makes 10sp 11-30, 11-32, 11-34 and 12-30 cassettes The ultegra rd may work with a 30t, but it's not a given. For anything larger you'll likely need a MTB type rd (any current shimano mtb rd should work just fine)

As a general rule mountain cranksets don't work well with road shifters and front derailleurs. You may be able to get it done if your seat tube is uniformly round and if your front derailleur is a clamp-on type.

Sorry but that just not true. Road shifter and mountain front derailers don't play nice together but there's no problems with the cranks. I've got 2 road bikes running mountain cranks. Neither has any shifting issues.


It would be possible to replace the cassette with an IRD 10-speed mountain cassette and a Shimano mountain type rear derailleur.
Your current low gear, 34/28 is pretty low, and there are no gears that will add oxygen to those higher elevations. If possible training in some hills or mountains before your trip to Colorado would help.

A 34/28 isn't really that low of a gear. Not for climbing at altitude especially if you don't live here. Training by climbing hills does nothing for the lowered pressure (not really lower oxygen content) that you find at our altitudes.

Another problem with any triple, road or MTB, is your front shifter may be double specific and would have to be replaced. I agree that a 34/28 isn't that low and either a triple crank (road or MTB) or a much deeper cassette is desirable. The SRAM 11x32 10-speed cassette would be a good choice but you would need an MTB rear derailleur.

I also don't consider a 34/28 gear to be long enough for serious, lengthy climbs. 28/26 is the least that I'll go out with for such a ride, and often something one or two gears lower.

You're right that you can use a road triple crankset and only use the middle and inner positions. TA Specialites makes a middle chainring with 46 teeth, which is the largest that you can get for that position. Middle rings with 42 teeth are easy to find. You can then keep the stock 30 tooth inner, or switch it out for a 28 or 26 tooth. I think this is a far better solution than going with a widely-spaced cassette - I like the gears out back to be closely spaced to allow me to stay in a tight cadence range all the time.

If you have a clamp-on front derailleur then this should be easy to set up by moving your front derailleur down and re-tuning it. If you have a braze-on mounted FD, then you might not be able to get it low enough.

cyccommute can you tell me what mtn cranks you are using? i'd like to purchase one I know that works.

This solution worked well for me:

I started with a 50-34 crank and an 11-25 cassette. Couldn't hack the hills.

I am now very happy with 105 triple crankset (30-39-50), 105 triple front derailleur, 105 brifters (fortunately the ones I had could handle either a double or a triple crankset).

In the rear I replaced the cassette with an 11-34 IRD 10-speed as mentioned earlier in this thread. They are ridiculously expensive and heavy as hell. I plan on trying out the new Shimano 10-speed 11-34 cassette (mtb) as soon as it comes available next month. XTR long cage rear derailleur.

As the frosting on the cake, I replaced the 30t ring on the crank with a 24t.

So my lowest gear is now 24/34.

It all works well together. The only thing I have to remember is to execute firm, crisp, definite shifts on the left brifter when shifting from the 24t to the 39t.

EDIT: It's such a nice setup that I duplicated it on my new touring bike that I have built from the frame up. Only deviation is that I used dura-ace bar-end shifters on the tourist.

The bar end shifters have a couple of big advantages:

Since the left shifter is friction, I quickly learned about how much pressure was required to shift out of the granny ring and now those shifts are smooth as butter (whereas with the indexed brifter there is occasionally the hint of a chain rattle if I don't hit it just right.

For night riding in the hills where I am constantly changing gears, the position of the shift levers helps me keep track of where I am gear-wise so I don't cross-chain. During daylight I can just look down, of course.

$70-$100 MSRP for a cassette is now ridiculously expensive? rofl

My CO "touring" bike: http://www.dim.com/~ryoder/SomaPhotos/IMGP0014.jpg

Ultegra: brifters, FD
XT: 22-32-48 crank, 11-34 cassette, RD

Sorry but that just not true. Road shifter and mountain front derailers don't play nice together but there's no problems with the cranks. I've got 2 road bikes running mountain cranks. Neither has any shifting issues..

I'm sorry but it is true. I was referring specifically to common problems with lowering the front derailleur on bikes with braze-on front derailleurs, and problems with the geometry of road front derailleurs with mountain type chainrings. I didn't say it couldn't be done, but often it cannot be done as a practical matter.




A 34/28 isn't really that low of a gear. Not for climbing at altitude especially if you don't live here. Training by climbing hills does nothing for the lowered pressure (not really lower oxygen content) that you find at our altitudes.

Actually I said training in hills or mountains would help, and it will.

$70-$100 MSRP for a cassette is now ridiculously expensive? rofl

$134 is the cheapest they come--and yes, that is ridiculously expensive.
http://www.google.com/products?q=ird%2010-speed%20cassette%2011-34&oe=utf-8&rls=com.ubuntu:en-US:official&client=firefox-a&um=1&ie=UTF-8&sa=N&hl=en&tab=wf

My CO "touring" bike: http://www.dim.com/~ryoder/SomaPhotos/IMGP0014.jpg

Ultegra: brifters, FD
XT: 22-32-48 crank, 11-34 cassette, RD

What's that doodad sticking up from the front of your rear rack--possibly a taillight mount?

I have a triple in the front, 50-42-30, and while the bike came with something silly like a 12-23, I swapped that business out right quick. I have a 12-32 cassette, and a shimano xt long cage derailleur. I could probably get away with a medium cage since I dont use the 50 (yet), but when I get stronger and need the 50 (right now I can get to about 23 mph at the highest gear setting on the 42 ring, although that is a bit rackety. Drop one or two cogs, and then I can do 20 comfortably), and that's really all I need. The upgrade was not cheap, but it made the difference between riding around in the baylands or up in the hills. I have a friend in the club who has a compact double and an 11-36, that cassette is huge. She is a high cadence person, so it works for her on steep bits of longer climbs.

cyccommute can you tell me what mtn cranks you are using? i'd like to purchase one I know that works.

I have a Race Face Turbine on my touring bike (ISIS bottom bracket) and a Shimano XT (Octalink bottom bracket) on my commuting bike. I use STI to shift both. I don't see why a external bottom bracket for either wouldn't work. I've found the XT trekking cranks (Shimano M771, 48/36/26) here (https://www.bikebuster.com/details/320174.html?vat=0&currency=usd)

What's that doodad sticking up from the front of your rear rack--possibly a taillight mount?

Right.
That puts the Dinotte taillight just above the top of the rack bag.

$134 is the cheapest they come--and yes, that is ridiculously expensive.
http://www.google.com/products?q=ird%2010-speed%20cassette%2011-34&oe=utf-8&rls=com.ubuntu:en-US:official&client=firefox-a&um=1&ie=UTF-8&sa=N&hl=en&tab=wf

for this price, it's possible to just buy a triple crankset and triple FD

FC-4500 tiagra or FC-3400 sora crankset is around $50~70
a non-series R553 is similar in price.

or for about $100 you can buy a 26-36-46 sugino XD600

In the near future, or maybe already available, SRAM and Shimano both will offer reasonably priced (less than $100 retail) 10 speed "mountain" cassettes in configurations like 11 x 32, 11 x 34, 11 x 36, etc. One of these cassettes, a mtb rear derailleur and a longer chain will be the necessary items to convert to much lower gearing for 10 speed drivetrains. I expect stock 10 speed touring bikes with real touring gear ratios to be fairly common by 2011. Not that tourists need ten cogs, and not that 8 and 9 nine speed chains aren't more durable, but with these new offerings, that's the nature of the industry.

I reside @ sealevel with flater terrain, but am planning a weeklong ride in colorado. I currently have a compact double 50/34 and 11-28 cassette. I did a similar ride last year and have some difficulty in the high elevation and steeper areas. I'd like to do the ride this year without struggling, but also keep the cost of components under control

I feel a 30t cassette would help a lot, but I'm unsure if it would work with a short cage ultegra 6700 RD. The 28t worked fine last year. If this would work, where could this be purchased

Another option is a mountain 2x9 crank or maybe even a triple mtn or road crank. It seems I could use the outer 2 chainring on the mtn crank or inner 2 for the road and just reuse the 28t cassette from last year. For the mountain, would I just have to lower the FD?

I'm open to any ideas.

No easy fix for this. You're a flat-lander and you're going to the mountains. A 34-28 low gear is sufficient (unloaded) gearing for the Rockies, but you haven't been training on hills. My advice is to A.) Suck it up and B.) concentrate up hills on really pushing over the top at 12 o'clock on your pedal stroke and pulling back at 6 o'clock while varying your seating position. When I was out of shape on hills I inadvertently stumbled on this rhythm that helped my up the hills:

1. Nose of the saddle for a few revolutions.
2. Back of the saddle for a few revolutions.
3. Click up 2 or 3 gears and stand for a few revolutions.
4. Gear back down. Rinse. Repeat.

I used to do this going way back to down-tube friction shifters, and it worked great.

In the near future, or maybe already available, SRAM and Shimano both will offer reasonably priced (less than $100 retail) 10 speed "mountain" cassettes in configurations like 11 x 32, 11 x 34, 11 x 36, etc. One of these cassettes, a mtb rear derailleur and a longer chain will be the necessary items to convert to much lower gearing for 10 speed drivetrains. I expect stock 10 speed touring bikes with real touring gear ratios to be fairly common by 2011. Not that tourists need ten cogs, and not that 8 and 9 nine speed chains aren't more durable, but with these new offerings, that's the nature of the industry.

touring bikes are still going to have frankenstein drivetrains. The Shimano 10 speed XT/SLX has changed the rear derailleur pull ratio so that barcons and STI levers will no longer be compatible. SRAM is better in that their 2x10 has the same cable pull as doubletap shifters, but they don't do triple in front.

I rode my Aegis carbon with a 53/39 crank 11-32 cog with an LX long cage, while towing a BOB trailer with 40 lbs of clothing/tent/sleeping bag. I rode Missouri to the Wyoming border up through Breckinridge Colorado. I was young and got strong real fast. You really need a triple.

SRAM is better in that their 2x10 has the same cable pull as doubletap shifters, but they don't do triple in front.

Check this out:
X0 2X10: http://sram2x10.com/?p=881
X9 2X10: http://sram2x10.com/?p=877

"Chainring options 2X: 26-39, 28-42 3X: 22-33-44"

So the *marketing* talks about nothing but 2x10, but the specs indicate there are triples available.
I don't know if that is a mistake, but I'm hoping it is not.

The Shimano 10 speed XT/SLX has changed the rear derailleur pull ratio .

Does that mean that the new cassette cogwheels will be spaced differently?
I was hoping to get one of the cassettes for my 105 brifter setup, thereby bypassing the IRD.
Any thoughts on whether it will work (with an XT long rear derail)?

Right.
That puts the Dinotte taillight just above the top of the rack bag.

I'm currently seeking the best way to mount my taillight. Could you post a few pictures of your mount showing how it's constructed/mounted? Thanks.

I'm sorry but it is true. I was referring specifically to common problems with lowering the front derailleur on bikes with braze-on front derailleurs, and problems with the geometry of road front derailleurs with mountain type chainrings. I didn't say it couldn't be done, but often it cannot be done as a practical matter.

It is not an issue with clamp-on derailers which are, by far, more common than braze-on hangers. I have a Tiagra shifting a 46/34/20 crank and an Ultegra shifting a 48/36/26 crank. Neither has any problems. Before I got the 46 tooth outer, I was using the Tiagra to shift a 44/34/22 and still didn't have a problem. The radius of the derailer and the length of the derailer are non issues. All of these shift nice and crisp

Additionally, if the bike were set up with a braze-on for a compact double, it would likely work with a 48 tooth trekking crank. There should be enough movement in the braze-on for that kind of difference.


Actually I said training in hills or mountains would help, and it will.

If you are coming to Colorado from a low altitude, training on hills may help your muscle strength but it does nothing for lung capacity or for the blood's oxygen carrying capability. Riding a bike with a high low gear requires more oxygen to your muscles and your lungs aren't going to provide it if they don't have the capacity to deal with the lower air pressure here. A lower low gear allows you to do the same work with less effort so the oxygen requirements are lower. Short of riding in a pressure chamber, there's really no way of increasing lung capacity or red blood cell volume other than riding at altitude. But those changes take weeks, months or years.

Short of riding in a pressure chamber, there's really no way of increasing lung capacity or red blood cell volume other than riding at altitude. But those changes take weeks, months or years.

You don't necessarily need to *train* at altitude, but just *live* at altitude to get the hemocrit level up.

Other options:
a) Sleep in a hypobaric chamber.
b) Sleep in a room with air processed by a machine that lowers O2, while increasing N, and scrubbing CO2.
(There was an article in Outside magazine about this a few years ago).
c) EPO.

It is not an issue with clamp-on derailers which are, by far, more common than braze-on hangers.

I believe that is no longer true. Over the last 15 years I have purchased 9 new road bikes for my family built by 3 different companies. Seven have been equipped from the manufacturers with braze-on type front derailleurs. It has not been possible to lower the FD's on any of these to fit anything smaller than a 50 tooth big ring. On my wife's Trek 5200 I ground down the bottom of the derailleur hanger enough so that we could install 49-39-30 chainrings.
Most carbon fiber frames and many other frames are equipped with braze-on type FD's.
Newer bikes with varying shaped frame tubes create problems with trying to lower clamp-on FD's.
Several forum posters have reported issues with trying to lower FD's enough to run small chainrings.
I think it is very irresponsible to imply that there is no problems changing cranksets and chainrings to smaller sizes without knowing more about the front derailleur and seat tube.

I think it is very irresponsible to imply that there is no problems changing cranksets and chainrings to smaller sizes without knowing more about the front derailleur and seat tube.

It is equally irresponsible to imply that there is a wide spread problem changing cranksets without knowing more about the front derailer. The majority of bikes still come with clamp on front derailers and a large number of them come with compact cranks. The best that AS2914 can do is to try it. If it doesn't work, there are other options.

AS2914: Check to see if you have a braze-on derailer. Even if you do, you may not be sunk. Just see how much adjustment you have left. Since Al1943 is concerned about the diameter of you seat tube (if you have a clamp-on derailer), check the diameter for 10 to 20 mm below the current clamp. If the diameter is the same, you are good to go. If not, you can always go to a "normal" road triple, i.e. a 52/40/24 tooth crank and a lower rear cassette. You'll need a mountain bike rear derailer for a anything over 30 teeth.

You don't necessarily need to *train* at altitude, but just *live* at altitude to get the hemocrit level up.

Other options:
a) Sleep in a hypobaric chamber.
b) Sleep in a room with air processed by a machine that lowers O2, while increasing N, and scrubbing CO2.
(There was an article in Outside magazine about this a few years ago).
c) EPO.

Training helps a lot;) Your other options are either very expensive or possibly deadly:eek::eek:

It is equally irresponsible to imply that there is a wide spread problems changing cranksets without knowing more about the front derailer.

Humm... is that a paradox or a contradiction?

Update

I bought a truvativ 52-42-30 triple crank off of eBay
It came with a gxp bb that will also work
With my SRAM compact rival crankset.

I installed the truvativ today using the existing bb.
I was surprised to find out I did have to touch the FD or cable
Tension. It shifts perfectly! The only thing left to do
Is remove the 12-25 cassette and install the 11-28

I might have to change the chain, but I'm confident
The 30-28 will work for me in the mountains and 42-11
Will be ok in the flats

Thanks for the input

If you're a flatlander and also plan to ride mountains from time to time, you should just bite the bullet and convert to a road triple outfit.

The road triple will give you both the higher gears you might like to have on the flats and going down hill in the mountains. It also will give you substantially better low gears for the mountains than any compact double. Unfortunately, there's no cheap solution, because what you now have is about as low as you can go with a compact double and a normal rear derailleur. Your minimum change will be to a very wide range, low MTB cassette and a new MTB type rear derailleur.

TA 33t Chainring?
Harris Cyclery has em.
Ramped and pinned and for 110BCD
Unsure how much the one tooth difference would help.
I know I tried a 30t using the 105ss that came with the PDG and...it didn'thappen regardless of how much I tweaked.