Carbon Wheels vs Aluminum Wheels: Questions & Answers

Aluminum rimmed Velocity wheel set.

Note: From time to time I get a comment from a reader that deserves to be answered in the format of a post here on the site. One reason being that the answer- or in this case answers- would take too much space up for a comment in the comments section. Secondly, the answer (s) may be of great use to a wider audience, and such answers would not be noted if they are buried in a comment section which many readers would not see. Finally, these sorts of topics are often searched on the internet and again- you won't come across my thoughts if they are buried in a comments section. So, today I attempt to answer the questions a reader asked.  

So, here we go. These are a couple of great questions that I will attempt to answer. Keep in mind that the answers may be different depending upon who you are, what your expectations are, and how you ride. While it is true that no one needs carbon wheels, we are not going to be taking that sort of an approach to logic today, because if we did, we'd all be riding fixed gear bikes with wooden wheels and solid rubber tires yet. Or you know.......walking. Anyway.... 

Question: Why do some folks think that they need carbon fiber rimmed wheels? 

Answer: Well, first of all, you have to be aware. By that I mean a couple of things. One- You need to understand why stiffer wheels in a lateral sense are a good thing. You have to understand why weight matters. You also may need to have ridden some carbon rimmed wheels to get the point driven home. Unless you care about those things, and have considered those things desirable in wheels for your bicycle, carbon fiber rimmed wheels are something of a joke. I mean, why spend more money than my entire bicycle costs? I was one of these people at one time. Spending hundreds of dollars on one rim? Are you joking? 

So, let's assume you were like that, like I was in my thinking about carbon fiber rimmed wheels, okay? What changed my mind? Well, a few things. One- I spoke with a rim manufacturer representative face to face at Sea Otter one year. His company was just coming out with carbon fiber rims for mountain biking. People were scoffing and laughing at this company for even thinking people would consider spending over 1500 for a pair of rims. The company man told me some things that made me think though. One story was that they had taken bare rims, held them above their heads, and smacked them on rocks as hard as they could to see if they could chip them. Beyond some cosmetic scratches, the rims were, seemingly, unbreakable. 

Aluminum rimmed wheels, like this Shimano GRX, represent fantastic value.

This made me pause. An aluminum rim would be destroyed by such an act. But I retorted that the price to get into their rims was still pretty ridiculous. He responded by saying that the wheels built with their rims were expected to last over a decade with daily usage. Hmm......pretty impressive. 

But still, I had built aluminum rims into wheels that had lasted over a decade with constant usage. Maybe not in mountain biking, but certainly as road and daily-driver wheels. And yes, I've actually worn through a rim side wall from braking all those years. So I get that part. But those wheels cost what? Maybe $500.00 back in the day? How many aluminum rimmed wheel sets could I get for 1500-2000 bucks? More than two, maybe three or four? Yeah..... 

So from a cost vs value standpoint, I needed more than some stories from a company man. Well, I actually got that 'more' when I was able to review a set of these rims for my old gig at Twentynineinches.com. I even was able to build these wheel myself. The lateral stiffness was off the charts compared to anything I'd ridden before. Why does that matter? Again- you have to consider these traits important to you and your riding style. For me, it was a game changer. The light weight at that sort of stiffness? You'd have to build an aluminum rimmed wheel with a much stouter- and heavier - rim to get this sort of performance. Hmm...... My mind was changing. 

Oh, and a quick aside on that particular carbon wheel set: I ran them for close to ten years, sold them, and they still are in active duty with no major issues that I am aware of. I never trued them. Not once after being built up. Try that with an aluminum rimmed wheel set that weighs 1400 grams or thereabouts.  

Now, was I ready to accept carbon fiber rim pricing? Not yet, no. I was still on the aluminum value bandwagon. Then came all this gravel road riding stuff. Time went on, things got far more competitive in the carbon rimmed wheel marketplace. I became privileged through my gig with RidingGravel.com to get my mitts on many different wheels. Some carbon rimmed, some not. And here is where I am at today with the value proposition. The next question takes us there......

Question: Help me understand how carbon is 10 times better than aluminum. 

Answer: This, for me, came down to noticing how much less energy it took to ride a carbon rimmed wheel set. And not because the wheels were lighter, although that is probably where our minds first go when we think about this. No, it was something else and had I not been riding on crushed rock roads, I doubt I'd have ever noted this, and I'd still be on the aluminum rimmed bandwagon. But I did note this and now I am definitely onboard with spending the money it will take to have my own carbon rimmed wheel set for gravel. Why? 

Probably the best money that you'll ever spend on a fat bike is for carbon wheels.

I rode a wheel set this past Summer for review and A/B tested it with a couple of different wheel sets. The aluminum rimmed wheel set, a Shimano GRX wheel set, is really a great value for the dollar. What are they? Sub $500.00 for the pair almost anywhere? Far less for a complete wheel set than any carbon rimmed wheel set, for sure. I rode those wheels, stopped to switch out wheels, then got on a set of FLO Cycling G700 wheels.  The difference in lateral stability was astounding. This 'wobbling' of the aluminum rimmed GRX wheels was causing me to have to expend a LOT more effort into handling the bike as I rode down the gravel road. The G700's were a cakewalk to ride in comparison. I have since noted a level of this with other carbon rimmed wheels as well. THAT makes it worth while to me. If I can ride a wheel set that makes riding gravel easier and with better handling? Sign me up. But there is another place where carbon rims really smacked my sensibilities upside the head. 

Fat bikes. Oh my! There is no comparison to having a tubeless carbon fat bike wheel to any aluminum wheel for a fat bike. The differences are so huge that any comparison is laughable. And by the way, I was one of the biggest critics of this idea several years ago. Take everything about why I would go carbon on a gravel bike for wheels and amplify that 10 times for a fat bike. The size and weight of this sort of wheel magnifies the good qualities a carbon fiber rim can bring to a level that, I'm pretty sure, even the biggest anti-carbon rim curmudgeon would have to agree is worth the bucks. It's so much easier to ride, and the lateral stiffness is awesome. 

Finally, it can't go without saying that carbon rim prices, and more specifically, carbon rimmed complete wheel sets, have dropped in price dramatically over the last 15 years. That FLO Cycling wheel set is well under 2G and I have seen some carbon rimmed wheel sets coming in under 1500 these days. Used to be that was the price of a pair of rims. So, value is getting better.

Conclusion: Is this the end of aluminum rims? Of course not! Aluminum will always have a place in my stable for rims and I will always have a set or nine(!) alongside the carbon rimmed sets. Aluminum is just too good of a value to ignore, and with careful choices and build up, you can approach the characteristics of a carbon wheel set for WAY less money. Plus, if you tend to crash out wheels a lot, maybe carbon is a bad idea then. Let's say you have a commuter bike, or you just don't ride a lot. Okay, carbon rims are definitely a stupid idea. Same if you don't care about weight, stiffness, or handling at the cutting edge. (At all or for a particular bike's use) If you are fine with your aluminum wheels, I get it. Like I say, I am a fan as well. It's just that for certain situations, I'd much rather be on a carbon rimmed wheel set. And as they say: Your mileage may vary.