3T Strada, 1x gearing

I’ve got the opportunity to by a 3T Strada at a very, very good price. I’ve got first refusal from a friend who is going completely over to mtb; the bike is immaculate, bought just before lockdown and has been ridden perhaps a dozen times.

However, I’m a little concerned about the gearing. The groupset is SRAM CX1 (stock, apparently), 50T and 11-36. I suspect that I’m going to struggle up some of the steeper climbs around here in 50/36, so I’d be looking to try and get a lower ‘bailout’ ratio without losing too much at the top end.

Does anyone have any ideas as to how I might do this fairly easily and economically? I’m not the best home mechanic, especially with SRAM, and as this would be an unplanned purchase, I’d really have to keep costs down to justify it.

I wondered about an XG-1175 cassette (10-42) and (maybe) a 46 or 48 front ring (probably oval). Assuming this is compatible (say if it isn’t!), I also assume this would need a new rear mech cage and a longer chain?

The other option would be to fit a 44 at the front and and leave the 11-36 on.

As I said I’m not terribly SRAM-literate so apologies if this is all a bit basic.

Or I could just be sensible and not buy another bike, but where’s the fun in that? :grin:

For a cassette with an 10t sprocket you’d need a different freehub, so I’d leave that for later.

Afaik the 36t will be the largest sprocket you can run with that rear mech.

Tbh I’d swap the chainring, which should be cheap, shorten the chain if you have to and ride it a bit to see at which end you’re running out of gears.

Bikecalc.com if you want to look at gear ratios.

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You can go up to 42 with the long cage version of the Sram cx1 rear derailleur.

The lowest gear on 50/36 is pretty similar to a 39/28 on a standard chainset, so you’ll get up most things, unless you’re used to spinning a compact chainset.

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Also a Shimano 11-42 cassette will work with the Sram Cx1 long cage derailleur, which should work fine, without having to change your freehub etc.

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I’d be equally concerned about big gaps between gears using a mtb cassette such as 11-36, let alone bigger.

As already mentioned, i would change the chainring. But it depends how you like to ride

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Thanks for both of these. I’m currently running a 52/36 and an 11-30 on my TCR, which is fine, but I’m not sure I’d want to go harder than that up the likes of Whiteleaf!

I’d tempted just to run it as is, and if Bison/Whiteleaf etc are a nightmare, think about switching it up.

Yep, a bit of a concern.

The idea of a 1x really appeals (for some reason, 90% of the mechanical problems I’ve ever had have been front mech related), but I take the point about potential cadence issues.

The bike would be a bit of a punt, if I’m being really honest, but I’m also being offered it at a price where I’d be very surprised if I couldn’t sell it for at least what I paid if I decided it was a no, 6 months down the line. On the other hand, like I said, I could always just leave it!

If I was you I would get the bike and just see how you get on! You wont lose much money if you get it for a good price.

I use my cross bike on the road which is 1x with a 40t chainring and 10-33 cassette. This is in scotland on lumpy terrain and its not often i look for lower or higher gears

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SRAM CX1 seems to use a standard 5-bolt 110mm BCD fitting, so there should be plenty of good after-market options for different chainrings from people like Praxis and Absolute Black.

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You can get all sorts of SRAM cx1 chainrings too.
I’d keep it at 50x11-36 setup and enjoy it.
I’m quite cadence insensitive, perhaps favouring lower cadence and out the saddle climbing, so your mileage may vary.

I’m putting together a crit bike with SRAM cx1 54t and 11-25 at the back at the moment…

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I’ve been riding 1x on the road for a couple years and don’t miss my front mech. With 42x11-36 I have most of the range I used to have, missing only the two highest ratios (50x12 and 50x11) which I never used anyway. With 42x11 I spin out at about 55 kph, but if I’m going faster than that it’s because I’m on a fast descent and I’d rather tuck in and focus on picking my lines. On the other end, 42x36 is low enough to do all the climbs I have within riding distance, which top out at about 13%.

I have heard the rule of thumb that, in order to keep your cadence changes smooth, you don’t want more than a 14% jump between neighboring gears in your cassette. The 3 largest jumps in SRAM’s 11-36 cassette are 14.3%, 15.4%, and 15.8%, but I couldn’t tell you where they are without looking, since they never bothered my legs.

Changing the chainring is an easy update if you find that it’s necessary.

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Exactly my experience. I use 1x only since a couple of month (GRX) with 42x11-42. I even ordered a SRAM XDR driver for my wheelset with the bike because I thought I might want 42x10. But honestly I don’t need that gear. Like described above I only spin out at a speed where I would stop pedaling and aero tuck anyways.

I might actually switch to 42x11-34. I already have that cassette from my old bike and it’s quite a bit lighter. I live in a flat country and don’t need the climbing gears.

Here is a quick comparison for you. If you run 42t in the front and keep the SRAM 11-36 in the back you basically just loose the top 3 gears compared to your TCR (if you spin slightly above 100rpm, that’s riding > 55km/h). In exchange your climbing gear actually gets a bit easier compared to your status quo:

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I ride mine with 50 / 11-32, i can get up 20% climbs, and dont struggle too much on the long 2km @ 9% climb in town. Doesnt really work if you wanna take it easy up the hills though

Id try it with the 50 / 11-36 before you worry too much, you will be surprised. Next step id just try a 46t chainring. Unless you wanna go fast downhill a 46t is pretty good, my 2nd bike runs a 46t big ring and Ive even raced crits on it and not run out of gears

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Definitely play around with gear-calculator.com as show in the screenshot above. It is a great tool to really over analyze gearing comparisons.

I used it to compare ratios between my 2x (50/34x12-28) setup at the time and possible 1x configurations. I went 46x11-36 (shimano) as it gave me just about the same low-end as the 34x28 and was willing to give up a little top-end I rarely used. Recently I switched to a 48t chainring to get a smidge more top-end after starting to do faster group rides, but other than that I would not have changed anything. Though now I’m tempted to throw the 46 back on since I’m not doing group rides this year. I really like the simplicity of the 1x and in 2 years have not encountered many situations where the gear I wanted was between the ones I had.

If you swap in a XDR freehub and get the 10-36 (12speed), with a 44 chainring you basically have the same low-end and are effectively losing 1 top-end ‘gear’. With a 46 you lose about half a ‘gear’ on the top and bottom, so pretty close to your current setup.

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I’m just saving up for a 1x Strada and I have test ridden one. Soon I’ll get the chance to have a Strada Due for a week, too. And yes, I live close to real mountains and can do lots of proper climbing. Long story short, I have thought a lot about gear ratios :wink:

I’d say you should change the chain ring first. Try to replicate the lowest gear you need, so for example if you have 34:28 = 1.21 now, then 44 : 36 = 1.22 will give you essentially the same gear ratio. You might be worried about your top end. But IMHO that is usually overblown. At 100 rpm in your highest gear you will do 51.6 km/h. On (false) flats that is the speed I top out at when all the stars align (wind, etc.). Are you quicker downhill? Sure. But at least where I live we have a thing called traffic, so I don’t push it too much. As you can see, you’ll likely have more than enough gears. Plus, as @Toby has already posted a screenshot of the nicest gear calculator on the net (here is a link), you see that the gears are pretty much as closely spaced, you are just missing 1.5 gears at the top. If you go for a 46 chain ring, you will miss one gear (50:12 = 4.17 is virtually identical to 46:11 = 4.18) at the expense of a slightly taller gear at the bottom, 46:36 = 1.28 roughly corresponds to 36:28 = 1.29).

You really think any of us will advise against spending someone else’s money? :wink: :laughing:

By the way, how much is your friend asking for? And is it the blue Pro variant or the red one?

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The largest jump on 11-speed SRAM road cassettes is when you go from 19 to 22 cogs in the middle of the cassette. Even their 11-28 cassette still has this tall jump. What you get in return are the magic gear ratios (meaning for almost all gears you have essentially identical ratios in big and small chain ring). Essentially, apart from a 15 % jump going from 13 to 15 teeth, the ratios are as close as other road cassettes. My 11-32 SRAM cassette has the same gear ratios, you just exchange the 36-tooth cog for a 14-tooth cog. You get SRAM’s 11-28 cassette by exchanging the 32-tooth cog for a 16-tooth cog.

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I’ve got this bike and yes as others have observed the chain ring is the easiest part to swap. The rear mech is a medium, so the stock 36 is the biggest you can go without changing that.

If you do swap the chain ring be careful with the nut for the “hidden” bolt, the one behind the crank arm is different from the others as you can’t fit a tool behind it.

I’ve been able to get away with the stock setup where I cycle in the South Downs and my power to weight ratio isn’t amazing :slight_smile:

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That’s interesting, thank you. If you don’t mind, what is your power to weight? I’m sitting at about 3.15 w/kg on FTP, and my only concern with the bike (other than trying not to get shot by the Mrs for buying it) is how it (read: I) would perform up steep climbs.

Also, if it’s not a stupid question, how do you remove the chainring if you can’t get a tool at the hidden bolt?

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What’s steep for you and how long are these climbs? What gearing do you currently use on these climbs?