Trail Bikes - Alloy vs Carbon

[pakora]

Living in western WA will make you realize you're dumb for insisting on riding a rigid singlespeed bike everywhere and finally decide to get a trail bike. I'm very big so it will be a XL 29er, and I like to go up, so it will be more on the XC side of things. (I've ridden a couple enduro and all mountain bikes that are slacker and have more travel and I hated them)

But let's not talk about suspension designs, wheel size and head angles. I think I've decided on a bike, but the question is - alloy or carbon. There are bikes that are identical but for alloy vs carbon frame and wheels. The difference is what seems like a lot of money to me - $1200.

My SS mtb is like 22 pounds. FS bikes that aren't XC race bikes are much heavier. I accept this.

I think my brain is locking on the the fancier spec - Carbon frame, carbon wheels, NX. I kicked the tires at my sponsor shop today and though they only had a large on the floor, they set up the suspension for me to take a spin on the bike path, and I demoed it as best I could - up and down the bits of hill and lumpy grass slope before it leveled out into sidewalk.

Part of my brain wants to get the alloy spec. It will be about a 1lb difference. A 30lb trail bike is the same as a 29lb trail bike or a 31lb trail bike, right? Then I can spend the extra dollars on... Kanza registrations? $1200 carbon wheels? Beer?

If I don't even know how much of a trail bike person I am, better to go for a decent spec and upgrade with the next bike when I know better? Or live by "buy nice or buy twice?"

[Joe Remi]

Hopefully you'll get some recs from the experienced side, but I'll throw in from being kinda where you're at.

Years ago I did a fair amount of singletrack on rigid bikes, but faded out of it before FS took over everything. Since then it's been road only, and recently I got to thinking that one of those newfangled suspension bikes that look like a motorcrosser would be fun to try. I looked at a few and saw all that carbon radness, but I fell on the side of "WOW that's a lot of money for a weight and stiffness/comfort difference you won't notice in the dirt with those big shocks soaking everything up."

So I snagged an alloy double-boinger on sale with what I've read are kinda-entry-level-but-not crap shock and fork. I haven't gotten to the trails yet (it's raining..I need dirt, not mud), but I figure it's good enough to tell me if mountain biking is a thing I want to do again at 56, and I can Craigslist it later for the full zoot carbon wallet drainer if I really get into it.

[nmrt]

All things being equal (components, cockpit etc), the only difference between a carbon trail bike and it alloy counterpart is only 1 lb? Usually, I have seen that the alloy trail bike in a company's line up gets built with lower specced parts. So, for more money ($1200 more) you ought to be getting a carbon frame and better parts. No?

Anyway, only you can answer your question. Do you feel a difference between the carbon specced bike versus the alloy one while trail riding? If no, the answer is simple. But if you do feel a difference between the two, then the answer is complicated. Simply put, is the $1200 difference between the two bikes worth it for you to experience the difference that you perceive between the two bikes.

one thing I find confusing. you mention that you are looking into the xc side of mtb bike. so, is a 30 lb xc bike not heavy by xc standards? or maybe thats how much it really is and i have forgotten about xc mtb weights these days.

anyway, good luck with your decision! i for one, would pick carbon because I always delude myself into thinking that I can always tell the difference between a carbon trail bike and it's alloy counterpart. and that i like the carbon version.

[pakora]

Ah, to be sure what I mean is a trail bike for me to be more toward cross country riding, but beyond the limitations of my current bike to ride black diamond trails. I don't mean I want a xc bike - you're definitely right that 30 lbs would be a very heavy xc bike.

Re the specs, many MTB companies offer identical specs for frames of different materials. Santa Cruz does this, say. It's from their site I'm taking the rough difference in weight.

[KonaSS]

Aluminum has come a long way. I would think that yes, the ONLY difference for most bikes between the aluminum and carbon bikes is the weight. Not flex or other characteristics. I wouldn't hesitate to get an aluminum bike if I was comfortable with the weight.

[fa63]

Having ridden both a carbon and aluminum Santa Cruz 5010 with the same specs, I couldn't feel a difference in frame material.

[johnniecakes]

If you have a mishap one will get a dent and still be rideable. The other maybe not.

[Hilltopperny]

I am very impressed with the last two carbon xc bikes I picked up. The first was a trek Superfly 9.8 which weighed around 23lbs and just felt faster and easier to climb on than any other mountain bike I'd ridden to that point.

The second bike which I still have is a trek Procaliber 9.8sl and it weighs a little over a lb less. Although I didn't think it was possible the Procaliber is an even smoother ride than the SF and it is the best riding trail bike I've ever been on.

I feel like the carbon bikes these days are pretty durable. They are built for offroad use after all and I didn't not see many reports of them being broken. All that said I'm sure higher end aluminum is likely to be fine as well. If you have an opportunity to demo one of each then do it! See if the extra weight savings and ride quality are worth it for you.

Sent from my XT1650 using Tapatalk

[NHAero]

I have a carbon FS Pivot that I bought slightly used for half of retail. I wouldn't spend $1,200 if the only difference is 1 pound. Lots of rider here on carbon, none broken.

[CunegoFan]

If you are looking at Santa Cruz then you might consider their carbon C rather than carbon CC. The only real difference is price and weight.

[peanutgallery]

Having ridden many aluminum full suspension bikes and then some carbon for a while I noticed the carbon ride to be a bit more nuanced. Feels more responsive and flexes slightly where it needs too.

Specialized does the comp level stumpjumper in carbon and aluminum with the same build kit. The carbon one isn't cheap, north of $4200.

As far as the weight and style, rode rigid and single 5 years ago and now I'm on basically an enduro bike. I stopped weighing it and I'm never going back because the newer style stuff is so much fun for what I ride. XC geometry for rocks and logs is too busy for me

As far a carbon breaking? I can store my flat kit in my downtube, how cool is that? On a serious note, the only broken one I've seen feel off a rack and got run over by a semi. I've seen nothing full sus/carbon/trail that was broken in action. Light cc carbon? That's another story

[Vientomas]

Having ridden dual susp. aluminum frame bikes only, perhaps my opinion is not fully informed...but, I have always been of the opinion that the frame on a dual suspension bike has but one function - to support the suspension components. It matters not what the frame material is, so long as it it stiff enough to allow the well designed suspension components to function properly. I don't know with certainty, but I assume the suspension was designed around a stiff frame, not a frame with built in flexiness.

Therefore, then, and only then, do weight cost become factors to consider. That being the case, if an aluminum framed bike is not significantly heavier than carbon, is as stiff or stiffer than carbon, but is significantly less expensive...I choose aluminum. My opinion for what it's worth.

[Jaybee]

I would worry about geometry, fit, suspension platform, shock quality, wheels, drivetrain before I started parsing frame material.

[Tony]

"Aluminium is making a comeback"
https://www.pinkbike.com/news/7-thin...d-in-2018.html

[Jcgill]

I was in a similar internal debate last summer looking at hardtail xc bikes....
My debate was to get a carbon frame with lesser components or get the alloy frame with mid tier components for $500 less.

I went with the alloy and am happy with my choice, the only time i second guess my decision is when i stare at the alloy bike hanging in the garage I think how much cleaner the lines would look if it were molded carbon instead.
Once i hit the trail and it rides and shifts great, i no longer question my choice.