Tech Stuff & other propaganda including:
click on the chart at left to see a full size stem fitting chart
click on the chart at left to see the Two Bike Gear Calculator, that will help you calculate your every gearing need / challenge
Why not double butted and tapered tubing?
If you make the frame stiff, won't it ride harsh too?
What's the deal with all the different kinds of titanium?
What should I look for in a titanium bike frame?
Why are you still building road and TT/Tri frames for 1 inch forks?
Why don't you follow the trend toward tapered steer tubes?
Why don't you use internal headsets?
Why don't you use BB30 bottom brackets?
Are you going to start building 27.5" MTB frames?
Brakes - Disc vs. Canti vs. Mini-V
Brakes - Hydraulic vs. Cable-operated
What IS a habanero anyway?
Making a tube's outside diameter smaller makes it more flexible. Tapering a tube has the same effect. While there are those who would argue that a tapered tube makes a more beautiful frame, I take a "form follows function" approach. Massive 7/8" (22mm) straight chainstays and 5/8" (17mm) straight seatstays reduce rear end flex to almost non-existent levels. To me, that's beautiful!
Double butting and tapering of titanium tubing are both very difficult and expensive processes that add cost but little or no value to a bicycle frame. In fact, once you ride a Habanero, you wouldn't want us to change a thing.
But how about all those pinched and squished tubes on some other bikes? Why do we stick to so many plain old round pipes? While funny-shaped tubes can provide marginally better resistance to force in one direction, they're not as good at resisting torque, or "twisting". When you think about it, that's really all you should be worried about with your top tube or down tube. Neither is going to flex up or down significantly (your tire will flex 50 times more), and the only way you'll displace them laterally is to hit something solid. But if you're a strong climber or sprinter, you will exert a lot of twisting force on both. A round tube resists this better, so we use round tubes. OK, so we DO use an oval top tube on the cyclocross frame (for portaging comfort, and because it looks cool) and an oval downtube on the Team Issue road frame (it also looks cool). We just don't try to tell you we did it to add some magical quality to the ride of the frame. In fact, look at how most "squished" downtubes are formed and you'll see they're designed to make the frame easier to build, not stiffer. The "tall" head tube end suggests you're trying to keep the head tube from flexing fore/aft (where the tube in in almost pure tension or compression anyway, and the movement is confined by the presence of the top tube much more than a little more height in the downtube connection). The "wide" bottom bracket end suggests you have a problem with your bottom bracket wagging from side to side (if your ears were cranks, that would mean shaking your head "no"). On the other hand, if you want to resist torque (what your downtube experiences in the real world) you should make the tube round if you want to make the best use of the material.
A bicycle frame is basically a bridge truss, with almost no vertical deflection. To put this in perspective, imagine supporting a bare frame by the head tube and rear dropouts on two large concrete blocks. Now, straddle the frame and jump onto the top tube. Ouch! What happened? You just discovered that the frame doesn't really flex very much in a vertical plane. The total deflection will only be a small percentage (around 3%) of the flex available in the bike "system", including tires, wheels, stem, handlebars, and saddle. As a result, adding or subtracting 5psi from your tires is likely to make more difference in comfort than going from the softest to the stiffest possible frame. Adding a front shock and fat, low pressure tires on an MTB will mask the difference in frames even more.
However, horizontal deflection is a different story altogether. Ideally, a frame will have almost no lateral flex at all. Lateral flex will cause several potential problems. If the rear end of your bike flexes under acceleration or climbing loads, you will have driveline problems, and possibly even rub your rear brakes against the rim. Flex in the bottom bracket area will cause several unpleasant problems. Your chain ring may rub against the front derailleur cage, the chain line may change enough to spontaneously shift gears (not a good thing), and the bike just won't "feel right". Deflection of the head tube will affect the handling and high-speed stability of the bike. Frames with a lot of lateral flex have a tendency to develop problems with high-speed shimmy.
Probably the best example of the perception of much of the "how frame material affects ride quality" issue was an article written about a blind test done on seven identical bikes built up with all the high-quality (steel) tube sets from Columbus. Even though the "experts" that reviewed bikes monthly could (according to their writings) wax poetic about the feel imparted by minute changes in tube butting or thickness, when they had no way of developing preconceived notions about the bikes they were riding, their abilities to discern these changes vaporized. Moral of the story? The placebo is, and has always been, an effective drug. To read the article, click here.
Build quality. The frames are fabricated by an honest-to-goodness aerospace builder in China, not some cookie-cutter bike frame factory. The welders are aerospace certified and have 10-15 years of experience (compare that with most builders). Their attention to detail and experience shines through in the fantastic single pass welds, and in the construction and alignment of all of the frame's components. They're also a great group of people that I am honored to work with. Plus, having lived in and traveled to China over the last 10+ years, I've seen the difference that the free market economy is making in the lives of the Chinese people, and I'm proud Habanero is a (small) part of that.
Service . We are a small company, and each and every customer is very important to us. We came to this business through a long time love of cycling, and with many years of customer service experience. A no-nonsense 5 year warranty against defects in material or workmanship plus a half-price crash replacement program are there to make it easy to choose Habanero. We are small enough to be flexible enough to meet your needs..... try us and see.
Price . How do we do it? Simple. We work very hard at it. No importers or distributors to add mark-up along the way. And, we work hard to keep our overhead to a minimum, so we can sell the frames for less than anything in their class. We care about quality and performance, not gimmicks. Sometimes even if it seems too good to be true, it isn't!
We guarantee you'll agree with us! Ride your "Habby" for 14 days - if you don't like it, send it back and we'll refund your money.
6Al/4V This alloy (as you'd probably guess by now) is comprised of titanium alloyed with 6% aluminum and 4% Vanadium. There are a lot of claims made about the strength of 6/4, but most of it is based on "textbook" numbers for sheet stock, not tubing. Until recently, 6/4 bike frames were all made from seamed tubing, that is, flat sheets which have been rolled into a tube and welded. Some still are. The problem is that the weld reduces the strength and resilience of the tube. In addition, 6/4 can only take about half the elongation that 3/2.5 can before it's permanently damaged. In the final analysis, you end up with a bike that's at best just a little stronger, but maybe less able to absorb punishment - plus it'll be a LOT more expensive. We think it makes more sense to save the weight elsewhere in the bike, where it won't cost so much per gram.
CP - or - Commercially Pure titanium. There are many grades of this material being used to build "low end" titanium bike frames (kind of an oxymoron, huh?). CP titanium is easier to machine than the more exotic alloys, and it is even more resilient than 3/2.5 (it can "stretch" more without failing). However, it doesn't have the strength of 3/2.5 or 6/4 alloy, both of which are at least twice as strong as most grades of CP titanium.
Quality. Look at the welds. Welding titanium must be done in a very clean, inert gas atmosphere. Contamination from oxygen or nitrogen can severely weaken the weld. In fact, the weld is the most critical part of the frame when it comes to strength. You're not likely to ever see a titanium bicycle frame broken in the middle of a tube, but only at the welds. As a result, the vast majority of ti frame failures I've studied have been due to the poor welding techniques of some of the low cost builders. A good weld will have smooth, void-free structure without discoloration. You'll be able to see the smooth transition from the weld to the tubing, not an overlapping "blob". Stay away from a frame with welds that look like they were squeezed from a toothpaste tube!
Design. The best bicycle is one that fits you and your riding style. At Habanero Cycles, our production frames are designed around time-proven concepts - not the latest fads. The road bikes have a "square" geometry, with the top tube closely mirroring the length of the seat tube in the middle sizes. This will accommodate the vast majority of riders - though custom geometry can be special ordered if you just don't fit a standard frame. The head tube and seat tube angles were chosen to provide a quick-handling ride, without the twitchiness associated with some "racing" bikes. The MTB frames are based around "NORBA" geometry, for all around best performance on singletrack, climbing and downhill. The TT/Tri frames are similar to the road frames, but with steep seat tube angles for optimum power and aerodynamics, and a slightly slacker head tube for proper handling using aerobars. The Cyclocross / Touring frames are the choice for the "all-rounder" bike. If you could only have one bike (yikes!) this would be the one.
Construction. There are some ways to "cut corners" when building a frame. We don't use them.
Seat tube clamps. Many titanium frame builders handle this important function with an aluminum clamp on over-collar. We give you a real "braze-on" clamp. We can do this because we reinforce this crucial area with a welded titanium insert, more than doubling the wall thickness of the top of the seat tube. This also allows you to use a standard 27.2mm seat post, even with the oversize flex-reducing seat tube.
Rivets - I *hate* rivets. Sure, you can save money by riveting on aluminum cable guides, shifter bosses, and water bottle bosses. But ultimately they won't be as strong (or as attractive) as a beautifully welded titanium "braze-on". (I use the term "braze- on" in quotes, because you don't actually braze titanium, but the smooth single pass welds are similar to items brazed onto steel frames) If you've ever been annoyed on a club ride by someone's bike "buzzing", it's likely because of a loose rivet.
Wishbone stays. I never liked these, regardless of frame material. They're easier to fabricate, but add to lateral frame flex, and limit the strength of the rear triangle. Just like your high school physics teacher taught you, there's nothing stronger than a triangle, so why build a bicycle using a "tuning fork" rear end?
Dropouts - The lowly dropout is undervalued in terms of the amount of strength it adds to the frame. Shaving a few grams from a dropout might seem like a good idea until you bend it in a crash. Habanero frames use a specially designed 7mm (more than 1/4") thick titanium dropout that has integral gussets to dramatically increase the strength of the rear end, and drastically reduce flex. These can be easily cold set if you do manage to bend it (unlike 6Al/4V dropouts).
Frame finish in order of expense, from cheapest to most expensive....
Painted. Painting negates some of titanium's most attractive characteristics, particularly in regard to maintaining the finish of your bike. Once you paint it, you'll have to worry about chipping and scratching the surface, just like any other bike. However, paint can cover up less-than-perfect construction and saves the manufacturer a considerable amount of money. It *is* a good approach if you don't happen to like gray or silver, I suppose. But if you do decide to paint your Habby, I promise I won't think badly of you.
Bead blasted. This is a very common method for finishing titanium bicycle frames. The frame is subjected to a stream of high-speed material that produces microscopic dimples in the finish. The end result is an industrial-looking dull gray tube. While this finish is inherently better than paint from a maintenance perspective, it's still quite easy to mar. A bump which would scratch a painted finish is likely to "polish" a section of the bead blasted finish. Unfortunately, there's no way to fix this without re-blasting the frame (which requires total disassembly of the bike and special equipment).
Brushed. This is the finish used on all Habanero frames. Once you own a brushed frame, you'll never want anything else. The brushed finish produces a soft, smooth silver finish (which I find much more attractive than bead blasted or polished, but chalk that up as personal opinion). It's very scratch-resistant, and minor abrasions are virtually invisible on the surface. If you do manage to scratch or otherwise mar the surface, a few passes with a ScotchBrite pad or 400 grit sandpaper restores the finish perfectly. This means that you should be able to keep your frame looking brand new literally forever!
Polished. This is what happens when you use finer and finer abrasive on the frame, until you end up with a virtual "mirror-like" finish. It's more difficult to maintain, since any minor scratches will show, and removing a scratch or abrasion will be considerably more difficult than a brushed frame. The polished finish also tends to show fingerprints, road grime, and sweat streaks more than a brushed finish. But if you like your bikes really shiny, there's no better approach.
Claim: By making the steer tube bigger, we can use less material and the fork will still be just as strong.
Not necessarily. Certainly making a tube's diameter bigger makes it stiffer - but you can't necessarily shrink the walls on a fork's steer tube without disastrous results. Also, it's been suggested that an "over-stiff" steer tube concentrates stresses at the steer tube/crown interface, rather than distributing along the entire length as well as a 1" steer tube might. And after all, the interface with the crown is where steer tubes will break, not in the middle. Also, the thinner a steer tube, the easier it is to crush it by tightening the stem. Lots of people find this out the hard (and expensive!) way.
For comparison's sake, let's look at the difference in weight between typical 1" and inch and 1/8 models of the same fork, all based on an uncut steer tube.
The Time Millenium Club fork came with a 330mm aluminum steer tube in inch and 1/8 format at 542g, and with a 300mm steel 1" steer tube that weighs in at 505g. Add 30mm of steer tube to the 1" CrMo steer tube, and the weight increases to 526g - actually lighter than the inch and 1/8 fork, and steel (with its better fatigue characteristics).
The Profile Design forks with their aluminum steer tubes all weigh in within 10 grams (that's a little over 1/3 of an ounce) of each other when comparing 1" and inch and 1/8 (with the lighter forks being the 1").
The Reynolds Ouzo Pro fork with its carbon fiber steer tube weighs a svelte 370g in 1" format, and 445g in inch and 1/8 format. Advantage, 75g to the 1" fork.
Now let's look at the rest of the bike (unless of course, you just want to buy a fork to admire by itself, in which case you can stop reading now). Bigger headsets are heavier. The difference between the 1" and inch and 1/8 format for some common headsets: Cane Creek S-2 vs S-3, 20g; Chris King NoThreadSet, 18g; FSA Orbit XL-II, 26g. How about stems? Again, bigger stems are heavier - though direct comparisons are more difficult since no one seems to make the "same stem" in both sizes. Add in the additional material required to make the head tube larger and it's easy to see that at best you MAY shave a few grams with a inch and 1/8 fork and frame, but chances are you're adding even more weight by choosing the "new improved spec", not losing it.
Then there's the subjective matter of "looks". Everyone's free to determine which looks better on a road bike, but I'll take the cleaner lines of the 1" headset and stem any time I can get it. It's easy to imagine that the smaller head tube is more aerodynamic (read, faster) but since I don't have a wind tunnel to test that theory I'll leave it as an unsupported hunch (for now).
And for my fellow retrogrouches (those of us who liked threaded stems because of their ease and range of adjustability without the need to reset the preload of the headset, and since they are easily removed or twisted for shipping) there are still a good number of stems and headsets available to outfit your 1" threaded fork.
Update: You may have noticed that virtually all of our frames are now spec'd for 1-1/8" headsets and forks. This isn't due to any physical need for a larger steer tube (though if it's going to help, it'll be on the larger frames), but only because it had become nearly impossible to find a 1" fork with a steer tube longer than 300mm. With a typical headset and stem, a 300mm steer tube allows virtually no spacers, and therefore, no adjustability on a 64cm frame. Similarly, a typical 300mm steer tube fork on a 62cm frame allows only a couple cm (0.8") of spacers, which I don't believe is enough for many (if not most) installations. We also included the 1-1/8" head tube on the Team Issue Nuevo frames because, well... they're "nuevo" (but we couldn't bring ourselves to slope the top tubes).
Will 1" forks be available 10 years from now? Almost certainly - though there won't be as big a selection as the 1-1/8" forks. This tends not to be a real issue, since in the overwhelming majority of cases, the fork will last as long as the frame anyway.
Slowtwitch.com article on Habanero Cycles and Mark Hickey
Slowtwitch.com article on the ultimate gravel / triathon training bike
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