Moisture

Hi all, So i've went for a 2x sram rival crankset, 36/46 compact for my road bike in 175mm crank arm size. My stock 39/53 crankset worked fine, but not enough low gearing with a 12-25 cassette and 53t was too much for most downhills I would encounter.

I know most people are partial to Shimano. I just went for Sram because options with the chainring tooth count I wanted was somewhat limited even in a standard crank arm size and I was limited to BB30, great bottom bracket, didn't want to change it.

I noticed that Shimano has it's own BCD design, so this could be an issue when swapping rings?

Those who are unbiased between the two or at least have experience with one or the other, which one did you find to be better overall?

I like that SRAM has more arm length options (167.5mm, 177.5mm...) and also more chainring combinations other than the standard ones like 34/50 or 36/52 .

Koyote

If you've already bought a new crankset, why are you asking for people's opinions on the decision? So that you can ignore, argue with, and misinterpret every single response that doesn't affirm your decision?

Moisture

If you're already here, why aren't you at least adding some useful input?

I am curious to see the two compared against each other either way, as sram is the less popular chioice.

Rolla

I have Sram Rival cranks on a couple of bikes, and I like them just fine. Other than square-taper BBs, I haven't used any Shimano drivetrain stuff for the last 20 years or so, so I can't compare. I don't think their popularity is any accident, however.

So run whatever floats your boat; I'm guessing it's all pretty good these days. And yes, the BCD of the chainrings has to match that of the crankset. I think Rival is 110.

seypat

It appears both have 110 BCD.

Iride01 

Yes even though a crankset has the same BCD as another, the rings may not swap due to other differences.

Reflector Guy

How steep are your hills? You say you need lots of low gears but on the other hand, the 53 is too tall on the downhills.... Not sure I follow but in your shoes I might have split the difference and gone with the common 50/34.

mprince

As long as the arm length and available ratios fit your needs (and derailleurs), there's really no comparison to be had.

livedarklions

So basically, is it unanimous that no one has noticed any real difference?

Probably do better on the BCD question in the Mechanics forum.

seypat

If it's the Rival 22 GXP, It looks a bit retro and cleaner than the 105. The 105 might be more aero. Whatever floats your boat. Which one will hold up in rainy weather better? That should be important to the OP.

Germany_chris

I’d not buy Shimano no matter the “benefit”

shelbyfv

Okaaaay. Let us know how the swap works out for you.

mstateglfr 

Almost all my current cranks are modern Shimano and Praxis. I had a modern SRAM crankset and it was perfectly fine. I shifted and the chain moved. Pretty uneventful. I can get along quite fine with a well set up square taper crankset from 30 years ago too though, so my opinion may not be the best to listen to.

Maelochs

Moisture ..... this is a common sort of thread here .... "I chose this over that .... which is better?"

The one you have is better because it is hard to ride far on a crankset you don't have.

And whatever anyone could tell you ... what use would it be? Are you going to sell what you have and buy something else if that is what people recommend? Judging by past posts ....

Pretty much all known-brand crank sets will work just fine. You don't get to have a worldwide cycling parts business by selling parts that don't work. So ... Both work just fine. There is no "answer' ....

What would actually make sense would be for you to put a few thousand miles on it and then tell us about whether the SRAM crankset works for you in your situation.

You have to recall, though .... you are the guy who told the world that all anyone ever needed was a 53-39 with a 12-25 cassette. So most of what you say we are going to filter through a few layers of incredulity .....

Anyway, glad you got the new crankset . Pretty sure riding will be a lot more fun when you don't have to grind up the hills.

Branko D

36/46 is an odd choice for road and inferior to the more common 50/34 or 52/36 which offer lower or similar climbing gears but more of a top end when you discover the joys of going downhill fast and when your fitness improves.

Otherwise, Shimano crank attachment and bearing layout is imo slightly superior to SRAM's GXP, but I have a Quarq GXP crankset and, well... :shrug:. It works, and the only practical difference is that removing the crankset out in the wild would be an interesting exercise even with the ratcheting multitool I have.
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SapInMyBlood

They're cranks??
BCD diameter matters, as does symmetric / asymmetric and number of bolts (3,4,5), or direct mount options

Koyote

Yes, Moisty seems to think that everything he owns is perfect for him, until he moves on to the next perfect thing. (I still recall him waxing poetically about some oval chainrings, and how much they increased his power, how they were sooo dreamy...and then someone pointed out that he had them installed incorrectly. )

I'm sure we'll soon be treated to a thread in which he tells us how great a 46/36 crankset is for climbing, that it's perfect, etc...Even though most of us, I'll bet, have never seen that chainring combo outside of a 'cross bike.

badger1

Our friend is probably too busy at the moment to respond. He has resumed giving 'fitting' advice over on the relevant sub-forum, and has returned to 'Hybrids' to offer some well-founded advice on "drop bars".

Never ending source of entertainment!

Moisture

Not sure why I thought my KHS uses a BB30.

I'm returning the Sram crank and getting 180mm arms 36/48

Koyote

shelbyfv nailed it.

Camilo

Have some Shimano cranks (105, Ultegra, Deore XT, non-series FC R700 (early compact) and some Sram (older Red and Force 10 sp, new AXS).

All of these work perfectly. Buy the one that fits your needs in terms of arm length and rings. FWIW, I've read recently something that matches my personal experience - crank arm length is virtually irrelevant within a few mm. Among the above are 170, 172.5 and 175 and I couldn't tell you which is which without looking at the fine print and/or closely measuring saddle height because that's the only difference they have - to me.

Lazyass

I have rolling hills where I live and my 46/36 is my favorite combo. I never run out of gear downhill and I virtually never use my 28 big cog climbing. With only a 10 tooth difference front shifts are lightning fast. Unless you're a weaker rider, a 34 is useless unless you live in the mountains or something. When I had a 34 I was always at the bottom of my cassette while at cruising speed and had to shift to the big ring too often.

SapInMyBlood

I've always lived near mountains. If you're climbing, use the small ring.
If you're not climbing, use the big ring.

​​​​​​??? Pretty straightforward. A 50-34 has been solid for me for years of road riding

Germany_chris

Chainring size is personal there's no correct or incorrect.

Branko D

No such thing as "shifting to the big ring too often"? Why would you ever go in the small ring if you aren't actually climbing? Especially with a compact and a wide range cassette, you cruise in the big ring; if the ride is flat and I'm going at it hard I'll sometimes do the whole ride in the big ring or just shift to the small ring for the final climb up to my house.

The idea behind a compact (50-34) or semi compact (52-36) with a big jump in the front is that you're cruising in the 50t or 52t, somewhere around mid to tall end of the cassette where the chainline is straight in ideal conditions (so, eg. 50-14, 50-15 and 50-17 on flat-ish ground) and everything runs smoothly and efficiently, and then when you have a proper climb, then you shift to the small ring and get the really low climbing gears. If you don't shift at the front often, that's expected really; it doesn't matter that the 16t jump in front is pretty big because it happens relatively rarely.

46/36 is cyclocross gearing.