Author Topic: 48/32 chainrings, an interesting innovation  (Read 996 times)

Serge_K

48/32 chainrings, an interesting innovation
« on: January 27, 2025, 10:36:26 AM »
For those with small legs / do a lot of climbing, China is now selling 48/32 rings, down from the retail classic 50/34. I can think of a lot of girls who never pedal at high speeds because they get scared and dont care about going fast, who could get more pleasant days in the saddle with smaller chain rings like that. Or chill dudes who also dont care about speed.
Or for bike packing / touring.

32 front, 34 or 36 rear, on a road bike, you can climb up a tree!
I assume FDs can be adjusted to fit these rings, but that's an assumption. afaik, it is 100% NOT a classic form factor.

https://www.aliexpress.com/item/1005006695090273.html
c.25 eur shipped for this type of double chainring (50/34, 52/36, 53/39) is what i've been paying, for reference.

Now Shimano may sell this, but if they do, i've never seen it.


Fast on the flat. And nowhere else.

Tilmanstoa5ty

Re: 48/32 chainrings, an interesting innovation
« Reply #1 on: January 27, 2025, 10:48:53 AM »
That's a really good development. I think a lot of riders are over geared. I had 46-30 front and 34 back on my canyon grail and it was amazing for climbing and i was still able to hit 70 km/h on some descents. Especially nice when you live in a hilly area and still want to stay in the lower heart rate zones going uphill.

I might consider building up an endurance type frame with that kind of gearing in the future.

kbernstein

Re: 48/32 chainrings, an interesting innovation
« Reply #2 on: January 27, 2025, 11:29:55 AM »
These have been available for almost a year in GXP, but GRX 48/31 is still my choice because they have a cheap PM option and I can't really find one for GXP with decent cranks. Such a shame they don't make truly modular cranksets, there's good potential

jonathanf2

Re: 48/32 chainrings, an interesting innovation
« Reply #3 on: January 27, 2025, 12:41:17 PM »
Senicx makes the best 3 bolt chainrings for the price and they align perfectly with Shimano FDs. Unfortunately they only make a 46-30t and not a 48-31t chainring for better low road gearing. For gravel I'd really like a 42-28t or 40-26t chainring. That way you could run an 11-36t and still have monster low gear!

courdacier

Re: 48/32 chainrings, an interesting innovation
« Reply #4 on: January 27, 2025, 12:51:12 PM »
Senicx makes the best 3 bolt chainrings for the price and they align perfectly with Shimano FDs. Unfortunately they only make a 46-30t and not a 48-31t chainring for better low road gearing. For gravel I'd really like a 42-28t or 40-26t chainring. That way you could run an 11-36t and still have monster low gear!

I've run both 48t and 46t in the past for road riding (with a cx 46t/36t double) and honestly couldn't tell the difference in daily driving. but it's nice to have options. both worked fine with a regular ultegra di2 FD.

toxin


amacal1

Re: 48/32 chainrings, an interesting innovation
« Reply #6 on: January 27, 2025, 02:30:08 PM »
I'm a big fan of this. I just received a Evosid sprocket, but I likely won't try to fit it up for a couple of months.

If a forensic investigator took a microscope to my rear cassette, I fear that they'd find suspiciously little wear on my 11t sprocket, lol. I've paid for the entire rear cassette, but I'm not getting my money's worth since there's basically an entire gear I seldom use. With a smaller chainring combo, I'll actually be getting my money's worth by using the whole sprocket!

What's the difference between 50t and 48t on the front chainring? Basically one gear further down on the rear cassette? So, if you weren't already finding yourself riding any amount of time in a 50(front)-11(rear) combination, then you absolutely won't miss having that 50t chainring.

Serge_K

Re: 48/32 chainrings, an interesting innovation
« Reply #7 on: January 27, 2025, 02:51:54 PM »
So, if you weren't already finding yourself riding any amount of time in a 50(front)-11(rear) combination, then you absolutely won't miss having that 50t chainring.

Big rings are mechanically more efficient than small ones, and if you're using the hardest cog, you're under geared (mechanically inefficient to angle the chain like that, which is the main reason why TT guys use monster chainrings: they use the middle of the cassette for their race pace). On ondulating terrain I'm very often running out of gears when I run 50 at the front, it's actually extremely irritating. I like fairly low cadences when I push watts.
But for a LOT of casual riders, smaller chainrings make a lot of sense.
Fast on the flat. And nowhere else.

s3si1u

Re: 48/32 chainrings, an interesting innovation
« Reply #8 on: January 27, 2025, 06:22:59 PM »
These have been available for almost a year in GXP, but GRX 48/31 is still my choice because they have a cheap PM option and I can't really find one for GXP with decent cranks. Such a shame they don't make truly modular cranksets, there's good potential

Have you checked out Aerozine? Most of their cranksets use a GXP standard and are modular. They ship with a 126.5mm spindle by default, but I ordered mine with the 130.5 spindle for a better gravel chainline and Q factor. They also come in a huge range of crank lengths, which have a flip chip allowing +-5mm of length adjustment. I'm a big fan of their stuff.
I use the X17 crankset on my gravel bike in size 160-165 (currently set at 162.5).
Link: https://www.aerozinebike.com/product/crankset/for-road-bike/x-17-series/aerozinex17-rd-arm-135-crankset/

kbernstein

Re: 48/32 chainrings, an interesting innovation
« Reply #9 on: January 28, 2025, 03:17:05 AM »
Have you checked out Aerozine? Most of their cranksets use a GXP standard and are modular. They ship with a 126.5mm spindle by default, but I ordered mine with the 130.5 spindle for a better gravel chainline and Q factor. They also come in a huge range of crank lengths, which have a flip chip allowing +-5mm of length adjustment. I'm a big fan of their stuff.
I use the X17 crankset on my gravel bike in size 160-165 (currently set at 162.5).
Link: https://www.aerozinebike.com/product/crankset/for-road-bike/x-17-series/aerozinex17-rd-arm-135-crankset/

No I wasn't aware of them but they don't really answer my needs either. I'm looking for PM, carbon cranks (ti spindle a plus) with GXP rings (for 48-32), and from what I understand the only place to put a PM on such a setup would be on the cranks themselves (or pedals). And as far as I know nobody makes carbon GXP cranks with a powermeter. I would have to compromise on the GXP rings to get a spider PM.
566g for just cranks without chainring or PM... no thanks

Serge_K

Re: 48/32 chainrings, an interesting innovation
« Reply #10 on: January 28, 2025, 06:34:21 AM »
No I wasn't aware of them but they don't really answer my needs either. I'm looking for PM, carbon cranks (ti spindle a plus) with GXP rings (for 48-32), and from what I understand the only place to put a PM on such a setup would be on the cranks themselves (or pedals). And as far as I know nobody makes carbon GXP cranks with a powermeter. I would have to compromise on the GXP rings to get a spider PM.
566g for just cranks without chainring or PM... no thanks

My setup has been vector pedals w racework carbon cranks, and chainrings that cost 25 eur and are largely disposable. I'm very pleased with that, because everything is cheap, reliable, and easy to swap. from one bike to the next, the pedals follow me. it's very easy to swap the chainrings (much easier than on shimano) so depending on the terrain / season, it's easy to change the chainrings. and if i break anything, i wont cry.
Why are looking for a bike specific PM, what is it you dont like about PM pedals? especially with Assioma making great road AND MTB pedals now.
Fast on the flat. And nowhere else.

Sander2177

Re: 48/32 chainrings, an interesting innovation
« Reply #11 on: January 28, 2025, 07:27:47 AM »
Jesus never mind granny set up this is the great granny set up lol!   I'm running a 54/38 and 11-34 for the Mallorca 312. 38 -34 is plenty for climbing

ZacItaly15

Re: 48/32 chainrings, an interesting innovation
« Reply #12 on: January 28, 2025, 07:49:03 AM »
After years of 50/34 11/28 10speed I move to 50/34oval 11/32 and I can climb pretty much everywhere in the road.
Gravel & adventure side, considering the lower speed the and the different style of riding, 34oval + 10/42 11speed is my goldilocks.

Sharing the same size (34 oval )  on both bikes is very cosy and I can compare the riding

Tijoe

Re: 48/32 chainrings, an interesting innovation
« Reply #13 on: January 28, 2025, 10:54:05 AM »
I've been running a 48/32 front set-up for over 2 years.   I love it!  When I upgraded my gravel bike to a 12 speed cassette, I went with a 10 tooth high gear.  (Therefore I didn't lose too much of my top end using a 48 front ring when combined with 42mm and wider 700C tires)   

At the time, my challenge was sourcing a "2X" 32 tooth chainring. (All the 32 rings being sold on Aliexpress are 1X - narrow-wide style.)   
- (Bikepackers started running 48/32 rings 5-6 years ago, but this hasn't been advertised/commented about very much. - 1 by 12s setups are still the rage.)

- I am running RaceFace cranks with a 2X spider.)

FYI:  Those GOLDIX-GXP chainring sets with the SRAM spiders were available more than 2 years ago.  When I decided to use 48/32 chainrings I wrote Goldix if they could manufacture them in the RaceFace crank mounting pattern, and they turned me down.   I ended up purchasing a separate RaceFace compatible spider and separate 2X chainrings

kubackje

Re: 48/32 chainrings, an interesting innovation
« Reply #14 on: January 28, 2025, 12:48:37 PM »
For those with small legs / do a lot of climbing, China is now selling 48/32 rings, down from the retail classic 50/34. I can think of a lot of girls who never pedal at high speeds because they get scared and dont care about going fast, who could get more pleasant days in the saddle with smaller chain rings like that. Or chill dudes who also dont care about speed.
Or for bike packing / touring.

32 front, 34 or 36 rear, on a road bike, you can climb up a tree!
I assume FDs can be adjusted to fit these rings, but that's an assumption. afaik, it is 100% NOT a classic form factor.

https://www.aliexpress.com/item/1005006695090273.html
c.25 eur shipped for this type of double chainring (50/34, 52/36, 53/39) is what i've been paying, for reference.

Now Shimano may sell this, but if they do, i've never seen it.

I have used 48/32 chainrings for few years on my all road bike with 2 sets of wheels for gravel and road. Never held me back and really appreciated the fact that it let me stay in the middle of the cassette most of the time. There is nothing wrong with running smaller chainrings. Few years later and I still appreciate smaller chainrings even though I'm way stronger now. Last season changed my 52/36 to 50/34 and feel better. can attack any climb and still ride tighter cassette. Also never had problem on the top end. But I'm also high cadence guy 95+