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Alloy vs Carbon Rims - Weight Difference?

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4.4K views 27 replies 24 participants last post by  Cleared2land  
#1 ·
After the i9 Torch rear hub exploded on my current set of wheels (old Colorado Composites carbon hoops back from ~2016), I've started to look at some lightly used/take-off options as a replacement. After looking through several options on PB buy/sell, I've been surprised by the basically non-existent weight advantage of carbon hoops vs alloy.
  • Forge + Bond thermoplastic carbon: 530g per rim, ~$1000 asking w/ i9 Hydra
  • i9 Enduro 300 alloy: 520g per rim, ~$785 asking w/ i9 Hydra
  • i9 Enduro S alloy: 520g per rim, ~$500 asking w/i9 Hydra
  • Cascade Racing Apex carbon: 510g per rim, ~$600 asking w/ Hope Pro 4
  • i9 Backcountry 360 alloy: 565g per rim, ~$800 asking w/ i9 Hydra
  • Roval Control 29 carbon: only lists complete weight at 1450g (but is by far the lightest out of everything) w/ DT 350.
I've been out of the wheel game for a while, so any recommendations for a specific set out of that list would be much appreciated. Based on what I've read, it seems that carbon wheels are generally considered to ride better, but it isn't universally agreed upon. I like the ~400g lighter weight of the Rovals vs everything else, but they do seem to be more of a XC wheel. Most of my daily riding fits within XC/moderate trail, but I do like having the ability to occasionally head to the bike park without really worried about breaking something. The Backcountry 360s are the heaviest and I've heard mixed things about how i9's alloy-spoked rims ride, but the bling is impeccable and perfectly matches my build.
 
#2 ·
You should also look at We Are One rims. (These are carbon....)
but a lot of riders have been upgrading to these because as the price has been very good.
Going by my LBS from the summer!
Just another option......
I ride Chromag (alloy) rims for the last 3 years and have not had any issues!
Also Spanks are pretty good!
Good luck!
 
#9 · (Edited)
You should also look at We Are One rims. (These are carbon....)
Agreed. Plus they have a 20% off sale on their premium Convergence wheel line now.

I have a set of Convergence Triad wheels (their most popular wheels).

The weight difference may be minimal but carbon changes the ride feel. I particularly like the increased precision.

EDIT: If you are going to focus on XC/ Trail instead of “do everything”, then:

- Rovals you mentioned.

From alternative brands I’ve tried with lifetime crash warranty:
  • Noble TR35
  • We Are One Factions
 
#4 · (Edited)
XC through Bike Park is a big spread. Unfortunately you'll need bike park strength rims and haul that weight around while XCing*. The lightest carbon All-Mountain rims will be around 400g, so around 1350g for the wheelset. Alloy will be about 100g/rim heavier (and flexier, and come out of true more easily).

*This is one of the reasons I recommend renting a DH bike when going to a bike park. There are other reasons. You couldn't pay me to ride my Trail or All-Mountain bike at the park.
 
#7 ·
If you are easy on wheels and don't need the durability of carbon, alloy rims are good enough and save a bit of $.

Some would also argue getting tires with lowest resistance makes more difference than wheelset weight as long as the wheelset is not abnormally heavy.

Makes more sense to optimize for most common case which is trail riding and rent DH bike for occaissional visit to bike park.


Most of wheelset weight is saved in:
  • Hubs
  • Spokes (use 28 vs 32 spokes and/or lighter spokes)
  • alloy nipples instead of brass (lighter vs more durable).

 
#10 ·
After the i9 Torch rear hub exploded on my current set of wheels (old Colorado Composites carbon hoops back from ~2016), I've started to look at some lightly used/take-off options as a replacement. After looking through several options on PB buy/sell, I've been surprised by the basically non-existent weight advantage of carbon hoops vs alloy.
  • Forge + Bond thermoplastic carbon: 530g per rim, ~$1000 asking w/ i9 Hydra
  • i9 Enduro 300 alloy: 520g per rim, ~$785 asking w/ i9 Hydra
  • i9 Enduro S alloy: 520g per rim, ~$500 asking w/i9 Hydra
  • Cascade Racing Apex carbon: 510g per rim, ~$600 asking w/ Hope Pro 4
  • i9 Backcountry 360 alloy: 565g per rim, ~$800 asking w/ i9 Hydra
  • Roval Control 29 carbon: only lists complete weight at 1450g (but is by far the lightest out of everything) w/ DT 350.
I've been out of the wheel game for a while, so any recommendations for a specific set out of that list would be much appreciated. Based on what I've read, it seems that carbon wheels are generally considered to ride better, but it isn't universally agreed upon. I like the ~400g lighter weight of the Rovals vs everything else, but they do seem to be more of a XC wheel. Most of my daily riding fits within XC/moderate trail, but I do like having the ability to occasionally head to the bike park without really worried about breaking something. The Backcountry 360s are the heaviest and I've heard mixed things about how i9's alloy-spoked rims ride, but the bling is impeccable and perfectly matches my build.
I've been really happy with Roval Controls on my Transition Smuggler as well as the Stumpjumper it replaced. I've ridden them in all kinds of conditions and never had an issue. They spin up quickly and the weight difference is noticeable vs. the alloy Crank Bros. wheels that came on the Smuggler. If you're hucking big jumps and drops in the park they are probably not the best choice, but otherwise I think they'll be fine for what you've described.
 
#11 ·
Appreciate all the advice - the sale We Are One is running is pretty temping. Definitely expensive, but there's something to be said for going brand new. A 28h Triad build with DT350 sounds pretty bomb-proof. If ordering to the US, are there any tax/customs annoyances that I'd have to handle? We Are One mentions customs fees for international order, not sure if they have US fulfillment to avoid that.

As for bike park vs my regular riding, the most air I get regularly is probably between 3-4 feet (which only occurs on 'skills park' features), otherwise there's just lots of typical east coast chatter. Lots of rocks and roots, some steep but short sections, so wheels tend to get hammered with lots of smaller impacts. Bike park is maybe a couple times a year if that, I like riding my own stuff since I feel comfortable on it from the get-go vs getting acclimated to a beat-on rental.

I don't seem to be too hard on wheels, with the Colorado Composites carbon rims I've been running being completely trouble free for many years. My track record has me thinking I could make the Rovals work, but obviously it would suck to crack a rim a year in vs spending more for a bullet-proof set of We Are Ones.
 
#12 · (Edited)
I like the ~400g lighter weight of the Rovals vs everything else, but they do seem to be more of a XC wheel.
The latest Rovals have a lot of tech in them that would give me the confidence to treat it equivalent to a rim that had more weight, due to how the material is used to reinforce the most dmg prone areas like the flanges.

That said, I've seen this thread on it, which goes to show that the warranty is a big part of the asking price.

 
#13 ·
I often think carbon is a material better suited for weekend warriors than pros. Almost set and forget. I feel like it's the same as frames. When carbon was embraced it was like, oh look how light we can make stuff. Now they're building to similar weights but are just so strong.

As mentioned carbon rims hardly require truing and can hold up to a lot of abuse. My last alloy rim got annoying as it got dented enough to no longer work as tubeless.
 
#14 ·
Carbon will be lighter for a given stiffness It can also be stronger. My rule of thumb is 500g alloy = 350-400g carbon, A 500g carbon rim would pretty much survive a nuclear explosion.

That Roval rim is 358g...
Reserve's carbon rims weights are as follows: DH: 516g, Trail: 449g XC: 385g ... all with lifetime warranty... and all heavy IMHO

I remember your previous thread. If I were you I'd go for a set of wheels like the Roval Controls. And I'd buy new to obtain the warranty and avoid buying someone else's issues - in a 2nd hand wheel, having to sort out breaking spokes, or replacing bearings, makes what might seem like a good deal into an expensive & time wasting pain.

I'd prioritise a light rim over an ultra-premium hub.

Given that Reserve offer the new DT DEG hub at 350 level, I'd consider them if you're happy with the rim weights.
 
#15 ·
I dunno about a nuclear explosion... but carbon is also more susceptible to catastrophic failure from impact/rock damage than alloy. I blew a rear WAO convergence wheel within a month on a rock drop I've done many times, so 🤷‍♂️

Carbon is stiffer and needs less maintenance... weight savings are marginal at best for intended use.
 
#16 ·
I've noticed that within the same category carbon is not much lighter but it is stronger. I've had a few sets of ARC30 (alloy) wheels that tend to come on Santa Cruz bikes and I've replaced them with WAO (carbon) wheels which weigh about the same. The difference is I can't keep the ARC30's from coming untrued, flat spotting, dinging, or cracking around the spoke holes. The WAO have been pretty much maintenance free. I true them about once every 3 years.
 
#17 · (Edited)
The biggest difference I noticed when I went to carbon wheels a few years ago was the stiffness for "point and shoot" line changes and turns. After riding my carbon wheels a while, I swapped back in my aluminum wheels to see if I could tell a difference and there was a dramatic difference in the AL hoops flexing in turns. The trick is finding the right hoops with enough compliance while being strong/stiff - I rode a buddy's carbon wheels from a popular brand and they were way too stiff to the point of being harsh.

I wouldn't consider myself a high finesse rider so I was pretty shocked that I could tell this much difference.

ETA: FWIW the ones I'm running and will buy again for my new bike are Nox Composites
 
#18 ·
+1 on getting carbon for strength and low maintenance.

When I was running allow rims (halo freedom 700g) I was getting through a couple a year.
Expensive when you take in to account wheel rebuilds.

A set of lightbicycle.com carbon rims just last.
I've still got my xc set from 10 years ago, I've had a DH set for almost as long.

I ran those xc rims down the fort William DH course with no issues (even though I destroyed a tyre, tearing it to pieces as I shorted a jump on to a rock garden.

Alloy rims are just too expensive and high maintenance to me.
 
#19 ·
Add me to the "carbon rims for less maintenance" train. My wheels are actually heavier than many alloy sets, but some of that is self inflicted (heavy hubs, brass nipples for longevity, 32 spokes). IME a good carbon rim itself is ~50-100g lighter per rim than a roughly equivalent alloy rim.

I've had my WAO Unions on Onyx classic hubs for... 3-4 years now? I've trued them exactly once (a buddy kicked a ~1in stick into my spokes), despite casing many many jumps, and my consistently bad line choices through rock gardens/etc.

In contrast my stock aluminum wheelset (which admittedly, was both a boat anchor, and very weak) took nearly constant truing (1-2x a month), and despite me using fairly thick tires was constantly denting, and by the end of the first year was relatively "D" shaped. So carbon has been much easier/more reliable for this bumbler.
 
#20 ·
You need to ask yourself. Do you have a rim smashing lifestyle. If you often dent an alloy rim you will likely smash a carbon rim. You will need a STRONG AF carbon rim.
The advantage of carbon is that it will take a bigger hit before it fails. But it has no plastic deformation. It will go from elastic to fail. The 500gram + carbon rims will be the go.

I have had fantastic performance out of Enve foundation AM30. So much so I have a set on both bikes now.

If all your alloy wheels are pristine with no dents after years use then you can go to a lighter 350-400 gram carbon rim. Just know that if you go to that lightness and you smash a rock or root hard they will likely fail.
 
#21 · (Edited)
After the i9 Torch rear hub exploded on my current set of wheels (old Colorado Composites carbon hoops back from ~2016), I've started to look at some lightly used/take-off options as a replacement. After looking through several options on PB buy/sell, I've been surprised by the basically non-existent weight advantage of carbon hoops vs alloy.
  • Forge + Bond thermoplastic carbon: 530g per rim, ~$1000 asking w/ i9 Hydra
  • i9 Enduro 300 alloy: 520g per rim, ~$785 asking w/ i9 Hydra
  • i9 Enduro S alloy: 520g per rim, ~$500 asking w/i9 Hydra
  • Cascade Racing Apex carbon: 510g per rim, ~$600 asking w/ Hope Pro 4
  • i9 Backcountry 360 alloy: 565g per rim, ~$800 asking w/ i9 Hydra
  • Roval Control 29 carbon: only lists complete weight at 1450g (but is by far the lightest out of everything) w/ DT 350.
I've been out of the wheel game for a while, so any recommendations for a specific set out of that list would be much appreciated. Based on what I've read, it seems that carbon wheels are generally considered to ride better, but it isn't universally agreed upon. I like the ~400g lighter weight of the Rovals vs everything else, but they do seem to be more of a XC wheel. Most of my daily riding fits within XC/moderate trail, but I do like having the ability to occasionally head to the bike park without really worried about breaking something. The Backcountry 360s are the heaviest and I've heard mixed things about how i9's alloy-spoked rims ride, but the bling is impeccable and perfectly matches my build.
You can get a really strong CF outer rim alone (not thermoplastic) that weighs about 430 grams. You are talking downhill strength at that point. Weight weenie CF wheels get crazy light, down to around 280 grams.

Weight for weight, a CF wheel is MUCH stronger than an Al wheel, but also cost a bit more.

Even a mediocre CF rim can knock off 200 grams compared to Al, or nearly 1/2# of rotating weight. That's enough to matter.

Also, be aware, that those cheap/ heavy CF rims can ride really stiff, resulting in a poor ride quality.
 
#24 ·
Appreciate all the additional advice. I definitely like how set and forget the current set of carbon wheels I've been riding are. They've needed pretty much nothing in the way of truing for years. If alloy wheels are likely going to need more attention, I'm leaning towards carbon just for the lack of hassle.

I'm currently taking a close look at the Forge+Bond 30EM wheels. I've got a brand new in-box set lined up for $1k with a private seller. Alternatively, I could do a We Are One Triad set for $1300 direct from We Are One. Any key points to consider either way? I can't seem to find much on the F+B wheels, but they seem to be quality hoops. Way too expensive at $2200, but $1k doesn't seem outrageous for a brand new set.
 
#25 ·
After the i9 Torch rear hub exploded on my current set of wheels (old Colorado Composites carbon hoops back from ~2016), I've started to look at some lightly used/take-off options as a replacement. After looking through several options on PB buy/sell, I've been surprised by the basically non-existent weight advantage of carbon hoops vs alloy.
  • Forge + Bond thermoplastic carbon: 530g per rim, ~$1000 asking w/ i9 Hydra
  • i9 Enduro 300 alloy: 520g per rim, ~$785 asking w/ i9 Hydra
  • i9 Enduro S alloy: 520g per rim, ~$500 asking w/i9 Hydra
  • Cascade Racing Apex carbon: 510g per rim, ~$600 asking w/ Hope Pro 4
  • i9 Backcountry 360 alloy: 565g per rim, ~$800 asking w/ i9 Hydra
  • Roval Control 29 carbon: only lists complete weight at 1450g (but is by far the lightest out of everything) w/ DT 350.
I've been out of the wheel game for a while, so any recommendations for a specific set out of that list would be much appreciated. Based on what I've read, it seems that carbon wheels are generally considered to ride better, but it isn't universally agreed upon. I like the ~400g lighter weight of the Rovals vs everything else, but they do seem to be more of a XC wheel. Most of my daily riding fits within XC/moderate trail, but I do like having the ability to occasionally head to the bike park without really worried about breaking something. The Backcountry 360s are the heaviest and I've heard mixed things about how i9's alloy-spoked rims ride, but the bling is impeccable and perfectly matches my build.
Carbon rims stay true. low maintenance, very strong. I had multiple flat spots on my RF arc rims, since switching to carbon they have been much more durable.