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Road Cycling “It is by riding a bicycle that you learn the contours of a country best, since you have to sweat up the hills and coast down them. Thus you remember them as they actually are, while in a motor car only a high hill impresses you, and you have no such accurate remembrance of country you have driven through as you gain by riding a bicycle.” -- Ernest Hemingway

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Old 10-06-13, 01:39 AM   #1
SethAZ
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help me sort out some gearing thoughts please

Hi all. Brand new to this forum. I ride a 2003 Trek 2300, with a standard crankset (53/39) and a 12-25t 9-speed cassette. Two weekends ago I did some mtn repeats with a couple others, for a total of 4600 feet of climbing. This is where I learned about compact cranks, since the other two guys had them, and were able to ride noticeably higher RPMs than me up that mtn.

So I ordered a 38t ring for the front (small improvement, but every tooth will help, and that's the smallest 130mm ring you can get), and a 12-27t cassette for the rear. They'll be here this week. We'll be doing a ride next weekend with around 6000 feet of ascent, and I'm looking forward to riding it with this new 38/27 ratio.

Well, all this new learning about gears and what hardware my bike has, and what's out there, got me thinking. On my 25-mile ride today I noticed that I was riding at my max comfortable cadence of 85 rpm (I am 6'3" and still weigh 270lbs, so my legs are beefier than usual cyclists) at around 20 mph, which is a very fast cruise for me (my typical 25-mile average speed is around 18mph), and I was in my 5th smallest gear! I changed to my 4th smallest gear and spun up to 85 rpm, and was going around 23 mph, which is far faster than I ever ride for a sustained period of time, unless I'm going downhill.

I'm thinking that my highest 4 gears are just wasted.

Bear with me here, I'm learning. I went to Sheldon Brown's gear calculator and started playing with different configurations.

I think a compact 50/34t crankset would probably be great for me, but I can't afford a whole new crankset right now. I already spent $56 on the new 38t ring and 12-27t cassette. I could probably afford another ring.

Can anyone explain why I shouldn't just buy a 48t ring for the front and compress the top gears down so that I'm riding in my 2nd or 3rd gear rather than my 5th smallest gear?

The thought hit me that although this stuff makes sense to me on paper, the fact that nobody sells bikes this way tells me there's probably a very good reason.

In fact, I was thinking a 48t/38t front and 13-27t cassette would probably be perfect for someone who rides in my speed range. There's gotta be a reason why I don't see this kind of setup anywhere.

Can anyone help clarify my thinking about this? What am I missing?
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Old 10-06-13, 02:19 AM   #2
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You can afford a new crankset:
http://www.probikekit.com/bicycle-cr.../10811009.html
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Old 10-06-13, 02:22 AM   #3
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Actually that setup is close to what they use for Cyclocross.
My race rig is setup with 46/36 x 12/25.
I can spin up hills fine, but lose top end speed on flats, & mostly descents.
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Old 10-06-13, 02:29 AM   #4
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Sigh. Apparently I didn't look hard enough. You're right, I could afford that. And it's a better option than swapping out the two rings on my existing crank.

This Trek 2300 has the 2003 model year Ultegra parts. Will this crank just bolt on to the exist bottom bracket? I'm still uneducated about the differences in mountings. And lastly, is there a reason why 10sp crankset wouldn't be compatible with the 9-speed system I'm running on the bike now? I know there are differences in the chain width, don't know if that's really an issue with this.
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Old 10-06-13, 02:39 AM   #5
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Sigh. Apparently I didn't look hard enough. You're right, I could afford that. And it's a better option than swapping out the two rings on my existing crank.

This Trek 2300 has the 2003 model year Ultegra parts. Will this crank just bolt on to the exist bottom bracket? I'm still uneducated about the differences in mountings. And lastly, is there a reason why 10sp crankset wouldn't be compatible with the 9-speed system I'm running on the bike now? I know there are differences in the chain width, don't know if that's really an issue with this.
One thing to take note of if its compatible with your bottom bracket. As long as your cassette, & shifters are still 9 SPD, it still a 9 spd.
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Old 10-06-13, 03:35 AM   #6
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Sigh. Apparently I didn't look hard enough. You're right, I could afford that. And it's a better option than swapping out the two rings on my existing crank.

This Trek 2300 has the 2003 model year Ultegra parts. Will this crank just bolt on to the exist bottom bracket? I'm still uneducated about the differences in mountings. And lastly, is there a reason why 10sp crankset wouldn't be compatible with the 9-speed system I'm running on the bike now? I know there are differences in the chain width, don't know if that's really an issue with this.
I have 9 speed Tiagra everything, except the crankset (which is 10 speed) and there are no problems whatsoever. I don't know about your bottom bracket though.
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Old 10-06-13, 03:55 AM   #7
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The bottom bracket shell width is the standard 68mm, it's BB-6500 in there now. From the reading I did after this was posted, it looks to me as if the hollowtech II BB will fit in my frame just fine. I'm not 100% on this, because it's the first time I've dealt with bottom brackets, but the reading I was able to find looks like this won't be a problem.

So I went ahead and ordered this crankset. Thanks Elvo! Assuming this fits fine in my bike, with the new 12/27t cassette I'll have way, way better high-cadence climbing ability. Two weeks ago we did some 9% grades during parts of our ride, and with my 39t/25t ratio there were times my cadence dipped into the 30s, and I was mashing for all I was worth just to stay upright. The new 34t/27t ratio will make it far, far easier.

I'm especially interested in seeing how the bike feels with the 50t large ring up front instead of the 53. It'll compress the high end somewhat compared to what I'm used to, and that's exactly what I'm looking for. I'm still tossing around the idea of one of these days making a 13-26t or 13-25t cassette to compress it a little further.
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Old 10-06-13, 04:02 AM   #8
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Everything depends on you weight, fitness & riding style. Compact will not necessarily make you climb better. Anything you take off the top of the gearing will slow you down when you are able to push that gear. Compact may be te answer for you, not saying it wot be the fix for "you". Longer rides & hill training will help you there.
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Old 10-06-13, 07:11 AM   #9
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The bottom bracket shell width is the standard 68mm, it's BB-6500 in there now. From the reading I did after this was posted, it looks to me as if the hollowtech II BB will fit in my frame just fine. I'm not 100% on this, because it's the first time I've dealt with bottom brackets, but the reading I was able to find looks like this won't be a problem.

So I went ahead and ordered this crankset. Thanks Elvo! Assuming this fits fine in my bike...
it will work fine, but you'll need to lower and adjust the front derailleur a little.

Your chain might be a little worn, so measure it for wear.
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Old 10-06-13, 07:55 AM   #10
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yeah...if you don't mind waiting at least a month for delivery from PBK...
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Old 10-06-13, 09:35 AM   #11
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I just upgraded bikes, and am now on a compact with 10 ape 50/34x12/27. My old bike that I'm offloading had a triple 9spd 52/42/30x12/25, and my current spare has 8spd 53/39x13/26.

On the new 10spd I'm finding the cluster around the top end of the gearing to be pretty useful when the pace picks up, be it on the flats or medium grade climbs. No issues with spinning out at the top end yet, getting up to the 30s and still pedaling on some downhills. Theres definitely some hills around here where I could spin better on the triple, but at the cost of speed I've found. I'm still getting used to where some of the gaps are, and going to the big ring a lot earlier than with a 42, but in general I like the compact.
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Old 10-06-13, 10:10 AM   #12
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new shimano sora crankset fc-3550 9spd
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Old 10-06-13, 11:32 AM   #13
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Everything depends on you weight, fitness & riding style. Compact will not necessarily make you climb better. Anything you take off the top of the gearing will slow you down when you are able to push that gear. Compact may be te answer for you, not saying it wot be the fix for "you". Longer rides & hill training will help you there.
I appreciate your comments. I'm a couple months from turning 45, and weigh around 270lbs. I used to weigh 380lbs, but around four years ago I got off my ass and lost a bunch of weight. My end goal weight is around 225, and for my frame type that's realistically about as low as I can go without becoming anorexic or contracting a terrible wasting disease. Bike riding helped lose a bunch of that, along with diet change and going to the gym.

I've been riding enough over the last four years (about 12-13k miles I'd say) that I'm much stronger than your average person who occasionally gets on a bike, but not up with the elite riders, or even with the very serious riders. My fastest 25-mile essentially-flat-but-not-really solo ride speed is around 20 mph at an average heart rate in the high 140s, and my typical 25-mile speeds lately (in the Arizona heat) have been around 18 mph to high 17s. As the temperature cools down I see this going back up to around 20.

The point is that I can't say for sure how my cycling will be when I finally reach my goal weight of 225, but given my body type I'm pretty sure that the high end compressed down a little by a compact crankset is not going to limit me.

As far as climbing goes, two weeks ago I climbed the 4600 feet we did in a 39/25 ratio, and in fact the first iteration of the climb I was stuck in 2nd gear and managed (painfully, but I got up there). My legs are made for mashing much more than they are for spinning, I guess. That being said, if I could make the 9% grades a couple weeks back with my standard crank, it's going to be much more pleasant with the compact one, and with the larger big cog in the rear it will be even better. Mashing up a mtn at 30-40 rpm royally sucks.

Yeah, the wait from PBK will suck, but the riding season here in Arizona has just begun, and I'll benefit from that new compact crank for many months to come, just apparently not on this one ride next weekend. Oh well. I'd already ordered the 38t ring for the front and the 12-27t cassette for the rear, so I'll install them for this ride, and do the compact crank when it finally arrives.
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Old 10-06-13, 12:42 PM   #14
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Where in AZ do you live?

I live in Peoria, and everyday is "riding season" (JMO).
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Old 10-06-13, 10:15 PM   #15
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Where in AZ do you live?

I live in Peoria, and everyday is "riding season" (JMO).
Opposite end of the valley from you, in Queen Creek. I agree that every day is riding season if you want it to be. For the less hard core, though, the temperatures are finally trending toward "holy crap this is perfect!". My hottest jog this summer was a 2-mile jog I did at 110 degrees. My hottest ride was a 25 miler at around 106 degrees. It sucked, but I've acclimatized to it somewhat as the summer progressed, and I bring two full ice water containers, and keep the pace down a little so I don't overheat.

If you are interested, I know three guys going down to ride up Mt. Lemmon next weekend.
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Old 10-07-13, 04:14 AM   #16
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I never under stood gears etc till I got an android app called gear calculator it's visual so the likes of me can understand it
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Old 10-07-13, 05:04 AM   #17
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The thought hit me that although this stuff makes sense to me on paper, the fact that nobody sells bikes this way tells me there's probably a very good reason.
You couldn't find a bicycle with 50/34 cranks? Here's a list...

http://www.fujibikes.com/bike/details/sportif-25

http://www.fujibikes.com/bike/details/sportif-23-c

http://www.fujibikes.com/bike/details/sportif-21

http://www.fujibikes.com/bike/details/sportif-15

http://www.fujibikes.com/bike/details/sportif-13

http://www.fujibikes.com/bike/details/sportif-11

By the way, I'm not showing this to be annoying or to "point something out". Just helping in case someone is looking for one.

EDIT: I found more...
http://www.myjamis.com/SSP%20Applica...cat_grp=road_2

http://www.trekbikes.com/ca/en/bikes...ies/domane_2_0

http://brodiebikes.com/2013/bikes/pact.php

http://brodiebikes.com/2013/bikes/pace.php

http://www.bmc-racing.com/int-en/bik..._disc/ultegra/

http://www.bmc-racing.com/int-en/bik.../dura_ace_di2/

http://www.cannondale.com/can/catalo.../category/916/

http://www.cannondale.com/can/catalo.../category/916/

http://www.cinelli.it/site/index.php...lliflypage.tpl

http://www.cinelli.it/site/index.php...lliflypage.tpl

http://www.devinci.com/bikes/bike_459_scategory_115

http://www.devinci.com/bikes/bike_458_scategory_115

http://www.devinci.com/bikes/bike_457_scategory_115

http://www.devinci.com/bikes/bike_455_scategory_115

http://www.diamondback.com/bikes-pav...d-century-disc

http://www.diamondback.com/bikes-pav...-road-interval

http://www.giant-bicycles.com/en-ca/...specifications

http://www.giant-bicycles.com/en-ca/...specifications

http://www.giant-bicycles.com/en-ca/...specifications

http://khsbicycles.com/bikes/2014-kh.../flite-150-14/

http://khsbicycles.com/bikes/2014-kh.../flite-280-14/

http://khsbicycles.com/bikes/2014-kh.../flite-300-14/

http://www.konaworld.com/*****_tonk.cfm

http://www.konaworld.com/zone.cfm

http://www.marinbikes.com/ca/bikes/d...rgenta-a6#spec

http://www.masibikes.com/bikes/steel...criterium-2014

http://www.masibikes.com/bikes/perfo...ellissima-2014

http://www.masibikes.com/bikes/performance/inizio-2014

http://www.masibikes.com/bikes/steel...le-strada-2014

http://www.masibikes.com/bikes/performance/vincere-2014

http://www.masibikes.com/bikes/performance/alare-2014

http://www.masibikes.com/bikes/perfo.../partenza-2014

http://www.mielebicycles.com/1239-vi...road-bike.html

http://www.norco.com/bikes/road/road...valence-alloy/

http://opusbike.com/en/bikes/road/sp...uminum/fidelio

http://opusbike.com/en/bikes/road/sp...uminum/othello

http://opusbike.com/en/bikes/road/sp...uminum/cantate

http://opusbike.com/en/bikes/road/pe...luminum/triton

http://opusbike.com/en/bikes/road/pe...minum/sibelius

http://opusbike.com/en/bikes/road/pe...aluminum/tenor

http://www.raleigh.co.uk/ProductType...&pt=14&pg=9043

http://www.raleigh.co.uk/ProductType...&pt=14&pg=9035

http://www.raleigh.co.uk/ProductType...pt=14&pg=10735

http://www.redlinebicycles.com/bikes/road/2013-ra1-

http://www.ridley-bikes.com/ca/en/bi...rion-c20-1411b

http://www.ridley-bikes.com/ca/en/bi...rion-c10-1411a

http://www.ridley-bikes.com/ca/en/bi...enix-c40-1409b

http://www.scott-sports.com/us/en/pr...cd20-tw-xxs47/

http://www.scott-sports.com/us/en/pr...-60-cd14-xs49/

http://www.scott-sports.com/us/en/pr...0-cd18-tw-l56/

http://www.schwinnbikes.com/bikes/ro...-2-mens#/specs

http://www.vitusbikes.com/road-bikes...#specification

http://www.vitusbikes.com/road-bikes...#specification

and the Torker Interurban
http://www.torkerusa.com/bikes/commute/2012-interurban

Holy crap, I just found a 48/36/26 road bike!
(OK, it's kind of a touring/commuting bike.)
http://www.mielebicycles.com/1242-an...road-bike.html

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Old 10-07-13, 07:02 AM   #18
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Here's what the OP posted.

"The thought hit me that although this stuff makes sense to me on paper, the fact that nobody sells bikes this way tells me there's probably a very good reason.

In fact, I was thinking a 48t/38t front and 13-27t cassette would probably be perfect for someone who rides in my speed range. There's gotta be a reason why I don't see this kind of setup anywhere."

How many of those bikes you found have a 48/38 crankset and a 13-27 cassette?
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Old 10-07-13, 07:29 AM   #19
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Here's what the OP posted.

"The thought hit me that although this stuff makes sense to me on paper, the fact that nobody sells bikes this way tells me there's probably a very good reason.

In fact, I was thinking a 48t/38t front and 13-27t cassette would probably be perfect for someone who rides in my speed range. There's gotta be a reason why I don't see this kind of setup anywhere."

How many of those bikes you found have a 48/38 crankset and a 13-27 cassette?
Oops.

This one is 48/38/28 with a 11-32 cassette.
http://www.raleigh.co.uk/ProductType...&pt=14&pg=9050

At least I found the unusual Miele bicycle.
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Old 10-07-13, 11:28 AM   #20
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Oops.

This one is 48/38/28 with a 11-32 cassette.
http://www.raleigh.co.uk/ProductType...&pt=14&pg=9050

At least I found the unusual Miele bicycle.
Thanks for the reply. Yeah, as BoSoxYacht said, I was thinking of bikes geared specifically for a slower speed range, for people who know they are never going to be cruising at 28 mph or whatever most bikes are set up for right now. My bike with its standard crankset and 12-25 cassette is currently set up to cruise in the top gear at over 28 mph. For serious racers that makes sense. For the overwhelming majority of the rest of us, a max cruise speed of 20 mph would probably be fine, but even for the sake of argument let's say 23 or 24 mph max cruise. That would still leave most of us cruising in our 2nd or 3rd highest gear.

My 12-25 9-speed cassette looks like this: 12 - 13 - 14 - 15 - 17 - 19 - 21 - 23 - 25
I'm currently cruising in my 5th highest gear, ie: the 17t cog. Notice that to shift up is a 2-tooth jump, and to shift down is also a 2-tooth jump. Think about this: the region of my gears where I do almost all of my shifting is the region where all the gear changes are by 2 teeth, which means I haven't got very close shifting. Every time I shift up or down my cadence changes by like 10 rpm, which is huge. Sure, I could do all my riding cross-chained on my 39t chainring and get into the single-tooth shift area of my cassette, but cross-chaining like that has its own problems.

This is my point: I don't understand why manufacturers don't sell bikes optimized for "the rest of us", giving us smooth, close shifting in the single-tooth region of our gears that we would actually use.

That's why I was daydreaming of something like 48t/38t (actually I'll amend this, I'd prefer doing this on a compact crank, so make it 48t/34t) and 13-26 or 13-27. Using Sheldon Brown's gear calculator, at 80 rpm the top gear of 48/13 still gives 23.7 mph top speed. At 90rpm it tops out at 26.7 mph. Using the 80 rpm cadence, my current max cruise speed of 20 mph still lies between my 3rd highest and 4th highest gear, but with a 9-speed 13-25 casette of 13,14,15,16,17,19,21,23,25 that falls into the gear region where I enjoy single-tooth shifts up and down.

Starting with this 48/34 + 13-25 setup, the max speed would still be a good couple gears faster than I can currently go, while giving me single-tooth shifts in the gear range where I do currently go. If I got so much better at cycling that I needed more headroom, I could always swap the 48t for a 50t up front.

Anyhow, I ordered the compact crank from PBK, and alredy previously ordered a 12/27 cassette, so when it's all here I'll be riding 50/34 and 12/27. This will be better than my current 53/39 and 12/25 setup, but still not optimal for where I'm at as a rider. To really optimize my bike for my current abilities, I'll have to swap the large ring in front for something like a 48t. And that's my point: where are the bikes optimized for your average riders? If I'm on a group ride and I'm one of the guys in front, and most of the riders in the group are below my level of riding endurance and whatnot, what does this tell you about these others? Well, for one, it tells me they're riding bikes geared far too high for them. They're riding way down their cassette 90% of the time, well into the two-tooth shifting range. It tells me their top 4-5 gears are simply wasted on them.

Anyhow, that's what I've been thinking about. Unhappy where my 53/39, 12/25 setup is at, I'm doing something about it. But without further customizations, even the compact crank isn't really going to "fit" my bike's gearing to where I'm at as a rider. It'll take some further customization of the large chainring up front, and probably a custom (or at least less common) cassette in the rear to accomplish that.

Unless I'm just thinking about this all wrong, and there's a very good reason average Joe riders like me are maxed out in our 5th highest gears and stuck shifting up or down two or more teeth at a time. I could be wrong.
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Old 10-07-13, 12:26 PM   #21
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Can anyone help clarify my thinking about this? What am I missing?
The "common" gearing for the masses assumes that sometimes you go downhill, in which case the extra top end gears are nice. The "racing double", which is another name for the 53/39, also assumes strong riders who might cruise in a pack at quite a bit faster pace than 20mph.

I think it often makes sense to experiment a little. Too few people do this. I would encourage you to get a 48 or 50 ring (might find better quality 50 tooth rings) and experiment with the gearing you get with that. The rule of thumb track racers use (since we use lots of different ring and cog fixed gear combinations), is one tooth on the back is worth three on the front. The rule doesn't work as well once the cogs get bigger than 17 teeth or smaller than 14 (or if you are trying to apply the rule to your small ring), but it's not a bad place to start. So, by going from 53 to 50, you are moving up your cassette one step. So, if you are normally cruising in a 53/16, you'll now be cruising in roughly a 50/15.

There are gear calculators on the web, or you can evaluate the gearing simply by dividing the teeth on the front by the teeth on the rear, if you want to get more exact.

Also, lots of touring cranksets use 48 tooth large rings (though many times these are with triple ring cranksets). Cyclocross cranksets sometimes use 46 tooth.
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Old 10-07-13, 12:34 PM   #22
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You'll like have more "granny" on tap. I'm running a 30/28 granny and while being all the way in full-gran is rare <g>, it is very nice to have it available. Cadence- or rather being able to vary it- helps me a bunch on climbs. High cadence when sitting, mash a little when standing. Usually two gears apart.
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Old 10-07-13, 02:47 PM   #23
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You'll like have more "granny" on tap. I'm running a 30/28 granny and while being all the way in full-gran is rare <g>, it is very nice to have it available. Cadence- or rather being able to vary it- helps me a bunch on climbs. High cadence when sitting, mash a little when standing. Usually two gears apart.
Well, I'll be using 53/38t and 12-27t this weekend, and after PBK delivers the new compact crankset, I'll be doing 50/34t and 12-27t. I've been looking at pre-built cassettes, and I think I see a 13-25 in my near future, for around $32. I think that will be just about perfect.

At least I'll learn a lot.
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Old 10-19-13, 04:42 AM   #24
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This thread and another thread prompted me to look over some details over and over again. And I started thinking what I never suspected I'd believe, that a double crankset may very well be more convenient than a triple. I mean you can get a complete range with a 34T chainring and be in the middle cog part of the time.

http://www.gear-calculator.com/#

EDIT: OK, I re-examined some stuff again and decided maybe triple cranksets are OK after all.

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