Hi David -
Properly built, ti and steel ride about the same, and can be built stiff, flexy, or anywhere in between. They both last a long time and can be repaired if they break.
Ti, as a material, is about 70% of the weight of steel, but as a complete bike frame, it's not quite that much lighter, because you need to use a bit more of it
(mostly larger diameter tubes) to get an acceptable ride and strength
(steel is much stronger as a material). So in the end, a ti frame is
about 10-15% lighter (a 4# frame in steel would weigh roughly 3.5# in
ti, in other words).
The problem I have with ti, and the reason I don't build with it, is
cost. A good custom steel frame (say, mine) is $1200 plus or minus a little bit. Decent custom ti starts at around twice that much, so you're paying an extra $1000+ for, at most, a half pound of weight savings. That's $5/gram, which is WAY too expensive - if you want a lighter/faster bike, you're better off spending that money on wheels, drivetrain, or other parts, where you can easily cut off several pounds and gain a lot of nice functionality. That cost difference applies for non-custom frames too - a nice non-custom steel will run $500-800 or so (obviously they vary a lot, but I'm assuming you're getting something relatively nice/lightweight), ti will be roughly $1200-1800.
Note that those numbers are for straightgauge 3/2.5 titanium. There are 6/4 butted ti tubes available which will save another half pound of weight, but the cost is astronomical - you will probably pay in excess of $3000 for a custom frame built with those tubes, so you're still basically at $5/gram.
If you're already buying the nicest parts available, then ti makes sense (ie, if you're planning to spend $5k or more). Otherwise, I feel it's a waste of money.
Ti won't corrode, which is great, but neither will steel if you give it even a tiny bit of care (ie, apply some framesaver, don't leave the bike out in the snow all winter). So to me, that's a non-issue. If you spend 5 minutes a year taking care of your steel frame, rust won't be a problem for decades.
Bottom line: to me, ti is not worth the money. I could build myself anything I want, and I ride (and race) exclusively steel bikes. Channeling Stan Lee, 'nuff said.
Saturday, October 02, 2010
Weekend rambling, steel and ti
I get a lot of requests for ti frames, or at least requests for an explanation of why I don't build them. Here's an email I sent back to one such fellow in response that sums up my feelings.