IMO if you want a commuter frame to last 20 years, crash resistance should be a high priority. The bike is likely to get banged around some in that much time. If it were me, I would look at Ti built to a touring spec, something similar to a Lynskey Backroad.

The design of the frame matching it's intended use is more important than the material it's made from. Ernesto didn't design his lightweight road bike to be bunny hopped for 10 years. That's MTB riding!

I broke my carbon frame (crash) 6 years ago. Calfee repaired it for $300 without voiding the lifetime warranty. I've also personally patched up the surface coat of my carbon frames with nail polish and some fine grit paper over a dozen times. The idea that carbon is not ready to be commuted on is utter nonsense.

Nah. That's a metal frame with inherently flawed bottom bracket design. I will never total a carbon frame by cracking the bottom bracket via use. For me, carbon is inherently more fatigue and wear resistant.

YMMV.

I recommend you reconsider aluminum. If you are going custom then no, but for off the shelf frames and bikes, aluminum will give you the best value and the best bike. Things most people need to consider when getting a commuter bike are reliability and resistance to theft (or resistance to heartbreak when theft occurs), and lightweight steel generally fails on both those points.

FWIW, I have a 14 year old custom Ti mtb and it is one of my most prized possessions, and I hope it lasts another 14 years. I am considering getting a Ti touring frame that the same company has left over from a previous year (non custom).
If you have the means to afford, and a safe place to keep it hidden while you are at work, then a Ti sport-touring or touring bike would be the bee's knees....
Here is a non-custom model to get your imaginations flowing...
Fargo Ti | Bikes | Salsa Cycles

Never say never.... Busted Carbon

Plenty of catastrophic, non-impact related failures there.

I'm not a carbon hater, every material has it's pro's and con's. Pick the one you like, make sure it's design is sound and maintain it properly.

Mostly roof-rack/garage-door and crash damage, though. And also either hasn't been updated in 4 years or nobody has broken any carbon since 2011.

I also ride hard and aggressive , hit potholes, bad pavement, ride up and down the curbs and all that stuff. Never broken any of my steel frames in the past 8 years. I also have an aluminium framed MTB and I beat the crap out of it, never wash winter salt out of it, it's still solid, no cracks. Sometimes I wish that my aluminium frame would crack so I could justify buying myself another steel framed bike.;)

It's very easy to take a painted bicycle and make it less attractive to thieves and other lowlifes with criminal element. I just don't see Ti as having some magical properties to prevent theft. There are plenty of painted bikes for sale out there, which are less attractive and don't attract unwanted attention....Then again , professional bike thieves know exactly what Ti is and it's impossible to fool them, OTOH a crackhead who is desperate to get his fix will steel anything including a Ti bike or a Wallmart BSO with a child seat on it.

I'm going to guess that if [MENTION=148271]KenshiBiker[/MENTION] is having a frame custom made, he has a place to keep it secure inside and theft is not a primary concern. Who routinely locks up a custom bike outside?

Meh. I don't think I'd ever want a custom commuter. Even with wads of disposable income. There's such a weight lifted from riding a beater places, especially when it comes time to pop into a store, or lock it in front of a restaurant for a few hours. Even if losing a custom bike would be no worse to you than me dropping my big mac on the ground, it's still just that nagging thought in your head.
This is why I recently hung up my new, nice, shiny CX bike as a commuter and bomb around on a mid nineties rigid MTB with balloon tires on it. I go a few mph slower usually. I get a tad more tired climbing hills. But I get a whole lot of peace of mind.

The only reason I'd say they're usually not great commuters is because most people who make carbon bikes market them to people who *need* a "racing bike" only(to do slow weekend rides on), and think the inclusion of fender/rack mounts would somehow make it no longer a race bike. Obviously some companies utilize these mounts though.

Though it's rare for most people to actually wear out frames, it is technically correct. A properly built CF frame should never wear out, it will take something catastrophic to make it fail, which would most likely destroy a light steel bike anyways. All steel faces the potential future of simply failing from a lifetime of use.

A properly built frame should last decades... I would discourage any of my customers from having a custom built commuter with such a high parts specification.

You will not be able to wear out a well made steel frame if you take care of it and if it was designed for the task it is given.

Ti frame + fenders + lights + rack/pannier and commuting just don't seem well matched. Has the price of a Ti frame come down to the level where folks don't care that much about OA weight? If I were to buy a Lightspeed, or some other superb (why do I want to spell that suberb? Ha ha) bike, I'd set it up with a balance of lightweight components and wheels fitting of such a nice bike. I wouldn't put together a commuter with a Ti frame.

If you won't have aluminum, then I submit that steel would be your next best choice. Something like this Nasbar TR1 Touring I see a lot of Surly LHTs in my area and they seem to make a really good commuter.

Carbon makes for a good frame building material but there is limited availability where fenders, rack, and canti/disc bosses are all available.

I think life is too uncertain to make choices about what I'll be riding in 20 years time.

Thanks for all the responses - really interesting reading. I'll try to respond to some of the main points,

I will be the first to admit, some of my "requirements" have no technical basis, but I'm OK with it, e.g., I had a bad experience with aluminum a long time ago. I will be the first to acknowledge that manufacturers have most-likely tweaked their designs such that it no longer feels like I'm riding a jackhammer, and if aluminum was the only frame material that checked all the other boxes, perhaps I'd consider it further. However, I know both Ti and SS do check all the boxes (and allow my anti-aluminum prejudice to continue unchecked), especially for a bike that I plan on keeping for 20+ years. As far as carbon goes, I'm not convinced that it's the best choice for a bike that will be used for 20+ years (besides, Calfee never returned my email inquiry - a sample of one, I know, but it just adds fuel to the fire). One of the main attractions of both Ti and SS is the ability to forego paint and not worry about scratches (until I'm ready to deal with them). Cro-Moly steel with a powder coat finish would be another alternative (although the local custom framebuilder insists on using wet paint - looks great, for a while . . .).

As far as cost goes, I'm aware this exercise will not be inexpensive, regardless of material. This likely will be the last bike I buy (well, there may be one more . . . :innocent:). I do have relatively secure parking at work (enclosed bike lockers in a parking lot that is patrolled by security guards); besides, that's what insurance is for. There is the concern about running errands after work, but in the past two years, I've only done that once or twice.

I also am a bit concerned about the ride characteristics of Ti, but I figured one of the advantages of working with companies like Seven or Moots, is that I'm most likely to be able to have the ride tuned to my needs. Same goes with SS, in which case the local custom frame builder would get the nod. My (custom steel) road bike rides like a dream. I'd happily commute on it (and I have), but I do worry a bit about scratches as I put it into the bike locker, and while it does have fender mounts, it doesn't have rack mounts, so I see it more as my Sunday, fair weather bike (maybe a few years down the road this will change); this commuter will be the foul weather, commuter, maybe even a little off-road. It may get wiped down after a rainy commute, but likely it won't, especially on the ride in to work (that's why corrosion resistance also is high on the wish list).

Since you really like your steel bike my gut says to go with SS since that will have similar qualities. It might come down to which builder you feel most comfortable with.

Just to muddy the waters:

http://applemanbicycles.com/wp-conte...40657-copy.jpg

This is a custom carbon framed bike. On these the carbon is raw, there is no paint to chip or scratch. I've met the builder. His background is in materials engineering. He makes road bikes, cyclocross/gravel bikes like above, and mountain bikes. Frames are guaranteed for 25 years. He's not taking off the shelf tubing and just welding them together in a custom geometry (like your other options likely are). The tubes themselves are custom engineered with the qualities you want.

Appleman Bicycles sells to people across the globe and he does repairs as well so if anything should ever happen, you can send it back to him. As far as I know it's a one person operation so there might be a wait involved in getting the bike. The plus side is that you're dealing with the same person from start to finish.

They are also pretty stealthy looking if you leave off the anodized blue components.

Seven also has Ti-carbon frames. ;)

A friend of mine had an older Trek Carbon-Ti frame. The Ti part cracked around the water bottle mounts. He got a new frame under warranty but it does demonstrate that Ti doesn't mean it'll last forever.

I am not aware of any carbon/ti bike that trek made. THey did a lot of aluminum/carbon BITD (which were notorious for having water bottle bosses come loose), but I don't know of any Ti. Do you know what model your friend had?

As a general rule, buying a bicycle with the expectation that it will be "the last bike you buy," is misguided and a great way to set yourself up for disappointment. Especially if you've only been riding for two years (I'm not clear on whether you've been riding longer and only just started commuting or if commuting is all of your riding). Time goes by, and your preferences change, and often your capabilities change as well. Sometimes because you're just older, sometimes because something happens and you get sick or injured. Planning to spend a big chunk of money on a bike is totally fine and great, but I think rationalizing it by thinking you're going to amortize it over two decades is pretty unrealistic. It might work out and that's fine, but it's not like buying a house. Justifying the size of a consumer goods purchase by how long you imagine yourself owning it at this particular moment in time is just not wise.

It was a Lemond (made by Trek). Don't know the exact model.

Most people who have Ti bikes love them and say it's better than anything they've ridden. Of course, part of that is self-reinforcing, since the investment cost is high. This leads people to want to believe it was money well spent. Blind tests are hard to do on bikes. But Ti sure is light, so it can't be all bunk.

I loved my old Ti Motobecane cross bike. Rode really nice. Zero issues with locking it up outside,it was when it was locked in my building's basement garage,with a U and chain,with security cameras,that someone used power tools to take it. Now everything nice stays in the apt.

FYI,there have been a couple postings over in the Folding forum stating the Superlight Bromptons ride better than the standard ones. The SL's have Ti forks and rear sub frames,and Ti or alloy(depending on the year) seatposts. Rest of the bike is the same,and the Ti parts have the same design as the steel ones(ie,one doesn't have a curved fork and the other a straight blade).

Perhaps buying anything as "the last one I'll buy" is a bit misguided. However, I know me, and I have trouble getting rid of things that are "perfectly good, other than age". It explains why I'm currently using a 37-year old bicycle as my winter commuter, and why I drive a 21-year old Honda; I'd like to get a new car, but there's nothing wrong with this one - just passed its smog test with flying colors last week (maybe I should loosen the oil drain plug a bit :lol:). If this new bike fits (and I have every intention of going to whatever length is necessary to make that happen, up to and including a frame built with custom geometry), I'll probably ride it until I retire in 10 to 15 years (and hopefully a few years beyond). Of course anything could happen, so who knows, whether I'll actually ride it for 15 years. Frankly, my real-life experience (for me, and me alone) is that whenever I've made a (relatively) large purchase (more than a few thousand $$$) with the intention that it was for the "short term", and I'd replace it soon, it's been a mistake - usually the item ends up sitting around, not getting used because I "settled".

As far as my riding experience goes. The Trek was my second "good" bike (the first one was so horribly oversized I couldn't stop without leaning the bike over about 45 degrees), so I've got about 40 years (more if you count the years on my stingray with the sissy bar and banana seat) in the saddle. Full disclosure: there was about 15 years there where I wasn't riding, due to recurring foot problems. As far as commuting goes, I've commuted by bicycle to other jobs in the past, but before these past two years, I was always a "fair weather" commuter, meaning I didn't commute if it was raining, or too cold, or if it was dark. Now, that none of those have stopped me for the past two years, I'd like to get a bike that is really more suitable for the purpose, even if it is more extravagant than most people would justify (I've known people who commuted using Corvettes and Porsches - I even had a boss once who would "commute" in his Ferrari 308 - I'm guessing the insurance on that thing is more than I'll spend on my "ultimate commuter", so everything is relative).

I'm not sure I'm trying to justify the purchase (especially to anyone except my wife and me). I thought I was just asking if anyone had any recommendations of whether to go with SS or Ti as a frame material. Pretty much everything else I wrote was just to provide context for those wishing to give their recommendations. Thank you for yours.