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Upgrading Crank Set

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Upgrading Crank Set

Old 07-21-19, 07:51 AM
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09box
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Upgrading Crank Set

I have a 50/34 crankset on my Fuji Sportif and are exploring an upgrade to something lower geared. Is it worthwhile to goto something like a 46/30 or even a 46/36? Would a mountain bike double such as a 38/22 fit? I run an 11-36 10 speed cassette on the stock Tiagra front/rear derailleurs.
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Old 07-21-19, 08:21 AM
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A quick look suggests this is a road bike, correct? Gearing is already pretty low. Your lowest ratio is a 34 tooth chainring on the crankset and a whopping 36 tooth largest rear cog. What are you looking to do as gearing seems pretty low right now. More information might help.
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Old 07-21-19, 09:14 AM
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Gearing is very subjective. If you feel like you need lower gearing go for it, it's your bike. Depending upon which crankset you choose you may need to change to a different front derailleur but they are not too costly. I feel that most bikes come geared too high for my tastes, 50 x 11 with 700c x 28 tires is about 120 gear-inches, 100 or under works best for me. A smaller crankset and a cassette with a smaller big cog and closer spacing will give more closely-spaced gears with narrower jumps between

Here is a calculator which will help to compare your current and proposed gearing choices: https://www.kstoerz.com/gearcalc/com...38,28&ighid2=1
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Old 07-21-19, 01:54 PM
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As long as you don't need the high ratios you are going to loose, then it might be okay. I don't think a mountain crank is a problem in general, but with that 11-36 on the back, you might need to take a close look at all the DR specs both front and rear to see if your DR's can handle that. The specs might be a little conservative, but when you are outside of them you can't blame the mfr for your ills.
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Old 07-21-19, 02:08 PM
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Yes, there are ways of getting lower gears.
But
If 34/36 isn't low enough for you on an unloaded road bike, I doubt you're going to find any magic with even lower gears.
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Old 07-21-19, 02:53 PM
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Originally Posted by 09box View Post
I have a 50/34 crankset on my Fuji Sportif and are exploring an upgrade to something lower geared. Is it worthwhile to goto something like a 46/30 or even a 46/36? Would a mountain bike double such as a 38/22 fit? I run an 11-36 10 speed cassette on the stock Tiagra front/rear derailleurs.
Boxer, is your 34x36 low gear not low enough for you, or is it that the rest of the gears are uncomfortably high, or poorly spaced? Your current low gear is pretty low, but your cassette is wide. Do you use the 11T & 13T cogs? Are you on the 50T ring most of the time?

If I were looking at a a 38/22 crank, I'd pair it with a narrow-range cassette such that I could do most of my riding on the 38 ring and just use the 22 for difficult hills. A 11-28 or 12-28 cassette would give you tight, comfortable steps with a reasonable high and a killer low.

In fact, I'd consider a 38x22 should I ever spring for an 11 speed setup.
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Old 07-21-19, 03:18 PM
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The 34/36 is low enough and I do use the whole cassette down to the 11t. Id say I use the 50 and the 34 equal due to the terrain here in PA. I've thought about going next to a 1x gravel bike so getting the drivetrain close to that with the low gear with my current setup was my train of thought.
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Old 07-21-19, 03:34 PM
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Of course the old-fashioned way (and my approach) to get a wide range with gradual steps in between is with a triple...
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Old 07-21-19, 03:46 PM
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If you use the 50 front 11 back combo going downhill, you will miss it sorely with anything less on the front. I'm 52/36 with 11-34 11-32 and am thinking of going the other way with a 53/39 front. I've been waiting till I get a chance to ride a rails to trails that is 44 miles of one to not quite two percent grade and see what gears I really rely on for flats. Based on the hills themselves I ride, I think it'd be a good choice.

Not sure where your 1x talk came into the picture, I guess I didn't follow the conversation well.

I only ride road and pavement so YMMV.

Last edited by Iride01; 07-21-19 at 03:53 PM.
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Old 07-21-19, 04:48 PM
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I should be mentioned the part about the 1x, my bad..
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Old 07-22-19, 01:35 PM
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I'm sorry. Your explanation is still unclear. Why is the single chain ring relevant to this? Do you want to eliminate the double chain rings on front and go to a single chain ring? Is that it?
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Old 07-22-19, 09:36 PM
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Originally Posted by Phil_gretz View Post
I'm sorry. Your explanation is still unclear. Why is the single chain ring relevant to this? Do you want to eliminate the double chain rings on front and go to a single chain ring? Is that it?
The thought of converting to a 1x has come to mind.
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Old 07-23-19, 05:44 AM
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I'm not sure what you really want. Maybe just keep the double as is? The 34 x 32T is plenty low, and since you say that you even use the 50 x 11T on occasion, I wouldn't recommend changing anything.
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Old 07-23-19, 10:35 AM
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I am building a 1x10 gravel bike and planning to run a 39T ring with a 11-36 cassette. Let me know how yours works out and I'll do the same if I get done 1st!

I have a 42T ring lying around which fits my crank I can use if it turns out to be too low geared. My tire size is pretty standard for gravel biking: 700x33C
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