Few questions about changing from triple to double. I searched on this, and learned a few things about gearing, but each person/situation is different.

On my Trek 1.2, I have an ultegra triple crankset 53/39/30 and a SRAM 11-26 cassette, with 700x25 tires. I ran the numbers and my gear inch range is from 28.8" to 120.5", and I mostly ride in the middle gears most of the time (46-75", or between 39/21 and 39/13). As you can probably guess, I'm more of a spinner than a masher.

I use the low gear for climbing steep hills (more than 8-10% grade) or past 70 miles when my legs are shot. I seldom use the large chainring unless I'm going downhill and I wanted to pick up some speed. So, I am thinking that the 53 chainring is a waste and I could be happier with a smaller chainring while I just coast on the downhills to save energy.

Hypothetically, if I keep the same cassette but switch to a compact double, say a 50/34, my new gear range would be 32.7" to 113.6". I'm willing to give up the high end, but I'm not sure if I want to give up the low end on the steepest climbs (think 10-15% grade hills around Austin, TX).

I suppose I could go for a 11-30... a 10 speed cassette and keep the same chain? If I added a 30 tooth ring to the cassette I have with the 50/34, my lowest possible gear would be 28.3", even smaller than the 30/26 lowest gear that I currently have.

And how much would this change cost? Don't need exact numbers... a ballpark $ would suffice.

Thanks! You all have been very helpful so far in the short time I've been here. Learning so much.

Who will be doing the change over?

I might ask the bike shop to do it.

Best to call some bike shops.
If you don't have a friend that is a mechanic.

You could Google some of the new parts for prices.

Before, you decide on something, I would check to see which ratios on your new gearing give you that range. If you have to shift the front chainring to attain that range it could get annoying.


What's your main reasoning for wanting to switch to a double?
If it's just the high end that you don't use, you could just get a smaller big chainring for your current cranks

Wow, you're right... I looked at my numbers, and the gear range I like to ride in, I would have to shift the front constantly on a 50/34. Yeah, that might get annoying.

On the other hand, if I change the 53 out to get a 50/39/30, the gears would be considerably closer and not so far apart. I'd get smoother shifting that way than if I got a compact double?

FSA Energy. 52/39/30 riding with an 11/25 cassette. Thats what I gots. Its nice. The bonus is is that I can change the cogs out if I want to cause the BCDs are popular.

changing to a smaller big ring will not make shifting a triple as smooth as a double. but like you said, not shifting a triple is smoother than shifting a double.

are you sure that 11-30 isn't too much for your RD? i've seen here that some guys have success using 12-28. just not sure about fitting a 30 without changing the RD. if i'm wrong, that'll be good news for me when i move back to the hills....

I'd choose a triple unless I was

1) strong enough to run a straight block up to a 19 cog (because I can ride with xPower 90% of critical power two days in a row instead of backing off on the second day when I keep my RPMs up over 90 and with some fatigue in my legs I'm not going to spin over 100 RPM and that's where the spacing works, and even before that it just felt better) which would imply an 11-21 for you if you want to keep the 11 starting cog.

In the 8 speed era I ran 50-40-30 x 13-14-15-16-17-18-19-21 so I'd have tight gears for plains rides east and enough bottom end to get up anything in the Colorado Rockies to the west. I added a 23 to the end when I wore out one of those cassettes and found Campagnolo had discontinued that combination, wore out my big ring, and decided that since 34x23 was close enough to 34x21 and two rings were better than three I should change to 50-34 in front.

That leads to #2:

2) able to do so while still keeping a decent amount of overlap between the rings, because it gets annoying when you don't have enough overlapping gears (apart from the fully cross-chained gears only 50x21 and 34x14 overlap with my setup), you have the wrong hill/wind/fatigue/recovery day combination, and are constantly doing double shifts moving five rear cogs for each one in the front. Where I used to use a silent 40x17 in the middle of the cassette I now have 50x21 and 34x14 which are noisier and probably lead to excessive side wear.

With 11 cogs I'd consider 46-36x12-13-14-15-16-17-18-19-21-23-25

If I wanted your gear range, I'd go for 53-39-24 x 11-12-13-14-15-16-17-18-19-21 although learning to spin and using 53/50-39-26 x 12-13-14-15-16-17-18-29-21-23 or 53/50-39-30 x 13-14-15-16-17-18-19-21-23-26 is a better idea.

My 50-40-30 triple shifted smoother than my 50-34 compact double that followed it.

Another option would be a 30-46 double from VO.
I went to a compact double from a 30/42/53 and don't regret the change down here. I run a 13-26 usually in the rear and haven't had to walk up a hill yet, even on the MS 150 through Bastrop park. If your really concerned you could keep a 11-28 around with the compact double.

not mine. my triple was 30/40/52, my compacts are the same as yours. no contest.

that makes more sense. i think the 20/22-tooth difference should make it harder to get a slick shift than dropping to a 16-tooth smaller chainring.

ps. insomnia sucks.

wkndwarrier, One of the bicycling problems living along the Gulf Coast is that there are a few gentle hills, but otherwise it's flat. Not far away, Sealy comes to mind, we can find some short nasty hills that flatland gearing isn't appropriate for. Austin and Kerrville are certainly not too flatland gearing friendly. Compromising the two riding conditions works best for me by using a triple on my distance bike. I'd suggest a 13-26/similar rear with your standard crankset as the 11T and 12T are often unused and more suited to a compact crankset, IMHO, and you can fill the middle with closer ratio gearing.

Switching to a compact double will require a new BB, crankset and a chain length adjustment in the least and go north of $200. A rear cassette swap is just that and cost roughly $50-75. 110 BCD compact chainrings can also be substituted.

Brad

The more I think about it, I'd rather stay with a triple because it gives me flexibility to work with all kinds of terrain. Houston is flat, but 50-100 miles away there are hills difficult enough for me to need the small third chainring (think Bastrop state park).

Right now I'm thinking of replacing the 53t with a 50t chainring and swapping out the rear cassette to get rid of the 11t & 12t and add more gear ratios in the middle.

Is there anything else I need to know before I do this? And should I wait until after the MS 150 (which is a month from now) before trying this?

That sounds pretty close to my gearing, and I spend most of my time in my 39 ring. I have a 50/39/24 and a 14-25 on the back, although I might switch up to a 52 or 53 because I get pretty windy days here which means huge tailwinds.

If I was you and could get stuff localy or with cheap shipping, I might just get a new cassette first, then a 50T if you find your big ring is still too big. The change from a 53x11 to 53x13 or 14 is a pretty big jump.

wkndwarrier, I'd regear as far as in advance of the MS150 as possible just to become aquainted with the revised drivetrain.

Brad

You are missing one other thing about the compact crank. As a spinner my self having the 39 ring is a lot more user friendly than the 34 as you would only be using 1-4 on the inner ring then 2 through 10 on the big ring. The 34 is to small a gear for spinning on. Crank and front deraileur. If i had a bike with the triple it would be with the 12-23 and use the inner ring for the bail out gear since this wouldgive a much better gearing for roller hills without mountain bike style gearing.

Here's a slick graphical gear calculator that lets you compare setups. I used to run the usual Ultegra 9 sp triple. I now run a SRAM compact crank and 10 sp11-28 cassette, which has the same effective range as the triple. I like it.

https://www.gear-calculator.com/#KB=2...F=2099&SL=2.15

I like Mike Sherman's calculator more since it takes a cadence range and shows speed bars for the cog combinations. For instance, visually I can see why I miss the 18 between 17 and 19 but don't care about having a 20 between 19 and 21.

https://home.earthlink.net/~mike.sherman/shift.html

I think that's a good idea. With the 50 big ring you may want to start with a 12 on the cassette. If you keep the 53 big ring you could start with a 13 on the cassette. If you keep the 30 granny gear on the triple you won't need anything bigger than a 26 on the cassette. If you ride a wide range of terrain, from flats to mountains there is no reason to try to do it all on one cassette. Cassettes are really easy to change out.

After reading these posts, I'll agree with sticking with the 30/39/53 triple for now and getting a 13-25 or 14-25 cassette. If the high end is still too high, then try the 50 large chainring. For slightly lower low gears and a similar high end you could do 30/39/50 with a 12-27/28

with an 11 for top cog a 46 should be fine for big chainring, + a 34 for the 2nd..
or a 48 -38 .. and a 13t top cog

I thought when you switched from triple to double you also had to swap out front and rear derailleurs. Front has a wider swing for the triple, and rear has a longer arm. You also have to switch out the front right brifter right? I guess you could make it all work without swapping these by setting the limit screws, but technically they are parts specifically for triples right?

Not really. Going from double to triple would necessitate new parts, but not the other way. Think about it this way: If you had a triple set up, and you decide to remove the inner chainring, would all the parts suddenly stop working? No. All that really needs to be done is screw in the front derailleur's low limit screw to lock out the inner chainring position. The chainline is narrower on a proper double, but again, you just need to dial in the limit screws and decide which left shifter position to lock out.

As it turns out, I got my bike inspected at a shop and the guy said that I'm gonna need to replace my chain soon. So I told him that I'll come back on Monday and get a new chain and toss in a new cassette while I'm at it. Decided I'll keep the 53T for now, and go with a 13-26 cassette when that chain gets replaced. Thanks guys!