Is anyone pushing and testing road bike geo?

ctp046

I really have two questions here:
1) Are any review sites objectively testing road bike geometry
2) Is anyone pushing the limits of road bike geometry

For question 1) I see a lot of sites testing bikes and reviewing how they feel. Are they harsh? Are they smooth? That kind of stuff. However, I haven’t seen any sites where they take them out on a test track and check lap times. Therefore anything with a 73 degree head angle and short wheelbase is described as “agile” anything slacker is “stable but not as nimble as a race bike”. How a bike feels is definitely important, but if I’m looking for the fastest bike possible this doesn’t tell me much.

The problem I have with just testing how a bike feels is that is that feeling fast is often different from actually being fast. Anyone who’s watched Top Gear’s “Star in a Reasonably Priced Car” segment will probably be familiar with the idea that “the lap looks slow which usually means it’s fast”. The idea being that if you take a good line the car won’t be on the verge of losing traction the whole time. I think something similar can be said for bikes. Coming from the mountain bike world, the fastest bikes often don’t feel that way. If you have more stability (usually the result of a slacker headtube angle, lower BB, etc.) the bike usually feels slower but lap times are often faster. There isn’t a lot I’ve found to demonstrate this on road bikes but I’m wondering if that’s because no one is doing the experiments.

A few areas of inspiration in the following links:
Chris Porter showing that reduced fork offset (on a MTB) might not feel the fastest but result in the fastest lap times (it’s also interesting to read the note on Chris’s Custom Bike at the end of the article):
http://www.bikeradar.com/mtb/gear/artic ... ent-45343/

The GCN crew showing that a longer stem (often described as making a bike feel like it handles like a boat) is actually faster descending:
https://www.youtube.com/watch?v=B69I_uayeMA

Now, neither of these prove my theory, but they do show that sometimes looking at how a bike feels gives a very different result than looking at lap times.

In addition, you’d think the added stability of more “progressive geometry” (long low and slack) would make things easier on the rider for the majority of the race (making it slightly easier to keep the bike rubber side down) and allow them to save some of their core muscle strength to really push through the corners when it counts. I would also argue that because road bike are often ridden at higher speeds than mountain bikes, the additional stability of progressive geometry would actually be more beneficial to roadies than MTBers.

A few of the counter arguments I can see coming my way are the following:
1) If long low and slack was faster the pros would be using it. Response: Maybe, but MTBer pros didn’t start out with progressive geo. In addition, pros are paid to make a specific brand’s bikes look fast. At the same time, it could be argued that they could still ride the brand’s endurance bikes (which some do) but my response is that many brands are building endurance bikes with the same fancy carbon layups that they are with their race bikes. Also pros seem to ride what they’re comfortable with (again this come back to feel not objective measures).
2) Racers need to be more agile so they need the geo we currently have. Response: Well has this been proven in a test yet? Maybe it’s correct but I’d like to see it proven. Further, as mentioned previously, as a roadie most of your riding is at high speed where I’d argue stability is more important and a more progressive bike would help with holding that speed through corners.

So, when it comes down to it. Has anyone tested my theory? I’d be happy to proven it’s all BS because someone actually put this to the test. Is anyone even making long low and slack road bikes?

mercia_man

There's nothing new in cycling. Long, low and slack has been tried before. The first mountain bikes in the 1980s such as my Overbury's had very slack angles. Then they went steep, now they have gone back to slack. And for the ultimate laid back road racing bike, have a look at Steve Bauer's Eddie Merckx bike for Paris-Roubaix in 1993. https://www.bikehugger.com/posts/the-ug ... rckx-ever/

Fads come and go but the typical 73 degree head angle for a road racing bike simply works, whether you are climbing, descending or riding in the bunch. Or if you are just an ordinary leisure road bike rider. As explained by expert frame designer and builder Tony Oliver in his book Touring Bikes, a road racing bike must have responsive steering and must steer as the rider leans the bike. He goes on: It only needs one rider to topple a complete group. A bike with too much fork offset will be slower to turn than the rest and a bike with too little offset will be too quick in changing course. If all bikes in a racing bunch have similar steering characteristics, tight formation riding is less dangerous.

burnthesheep

You could totally do it in a data driven way.

You could do this:

Setup a set of 3 surfaces. Let's call them mild and high frequency, medium and low frequency, and very harsh and "acute" or single impact. Fit the bike seat and handle bar with an accelerometer or something. Lot the values of a rider going over those standardized test surfaces.

Then you could literally score a bike's comfort or road handling based only on the data.

You can weigh a bike and frame, that's easy. You could also invent a frame "torqueing" machine that tests things.

Just $$$ and time.

bristolpete

I think the raft of endurance bikes are trying to prove smoother is faster. Defy, Synapse, Roubaix and co. Certainly there are sections of road where I live where a longer wheels base, higher volume of tyre and right frame will always outperform as super rigid 23c 'race bike' as you are not bouncing about laterally left and right, just rolling forward without the back wheel kicking up as the front wheel does.

svetty

Too many variables and subjectivity here for any meaningful overall view TBH. The real limiting factors are the UCI rules governing permissible race bike designs - and the manufacturers/public adherence to what they expect a proper bike to look like.

buckmulligan

To be honest I think it's a complete red-herring to try to compare road cycling to mountain biking or even cyclocross.

Speed in terms of road cycling is about one thing: Watts.

Be that in relation to your weight when you're going up mountains or to your CdA when you're TTing; power output is king. Bike handling, whether that is resulting from the inherent properties of the bike or the rider's ability, has very little impact on speed. The bike geo that can get you into the most aerodynamic position that you can maintain for the duration of your ride/race (and not overly compromise your ability to put out power) is going to be the quickest. The terrain that you typically cover on a road bike just doesn't penalise you in terms of speed for poor bike handling as it does with MTB or cross.

CTP046 wrote:

Coming from the mountain bike world, the fastest bikes often don’t feel that way. If you have more stability (usually the result of a slacker headtube angle, lower BB, etc.) the bike usually feels slower but lap times are often faster. There isn’t a lot I’ve found to demonstrate this on road bikes but I’m wondering if that’s because no one is doing the experiments.

As an aside, I notice that the opposite is true watching the downhill skiing highlights on Ski Sunday. The guys who go the fastest are the ones that really push the limits and look as though they are going to crash at every corner! The guys that look fast, smooth and in-control are the ones losing a tenth of a second on every turn.

Monty Dog

A lot of the stuff written in bike reviews is marketing fluff purely generated to excite potential buyers interest, generate new sales and keep the 'journalists' in a job. In the MTB market in recent years its been particularly bad - the outcome is that sales are falling because consumers have lost confidence in the confusing / conflicting amount of choice in wheel sizes / boost / slack / plus - for the vast majority of users they never to use that level of capability. IME with road bikes, the actual bike makes even less of an impact (assuming that optimum position is a variable of the rider) as it simply comes down to watts. You'll see it yourself if you race - the number riders on uber-bikes with expensive wheels getting whooped by guys on lesser machines. I also occasionally ride MTB races and the number of younger guys I beat on their carbon full-sussers when I'm riding a rigid hardtail with untrendy, oversize wheels.

joey54321

A lot of people seem to be confusing geometry/handling with smoothness, they are linked but not the same. Pretty easy to determine the smoothest bike with data, based on the assumption smoother is always better. But with bike handling/geometry many things are subjective, some people like a 'quicker' handling bike whereas other people prefer it to feel more relaxed.

buckmulligan

The OP doesn't mention "smoothness" at all.

He wants to know whether frame geometry and handling associated with it affects speed.

Monty Dog

Skiing analogy isn't that realistic in comparison to cycling as only on downhills do you ever get the chance to really let the bike run - from someone who previously raced on skis - it was generally the smoothest skier who could carve cleanly, managing the transitions to get the skis running between turns and wasn't clattering around and losing speed going sideways. In terms of the impact of the bike on speed - by the time you're eliminated rider's power, stamina, position, aerodynamics, clothing, rolling resistance, road surface you're only left with a few % of the whole energy equation - so even if one bike offered a dramatic 50% improvement over another, you're only talking about fractions of a % overall. As some have also found that big-tubed, aerodynamic frames with deep section wheels are very good at transmitting power to the road, but also extremely efficient at transmitting every irregularity of the road through your body - beating you up after a few hours, accelerating fatigue

bristolpete

Monty Dog wrote:

Skiing analogy isn't that realistic in comparison to cycling as only on downhills do you ever get the chance to really let the bike run - from someone who previously raced on skis - it was generally the smoothest skier who could carve cleanly, managing the transitions to get the skis running between turns and wasn't clattering around and losing speed going sideways. In terms of the impact of the bike on speed - by the time you're eliminated rider's power, stamina, position, aerodynamics, clothing, rolling resistance, road surface you're only left with a few % of the whole energy equation - so even if one bike offered a dramatic 50% improvement over another, you're only talking about fractions of a % overall. As some have also found that big-tubed, aerodynamic frames with deep section wheels are very good at transmitting power to the road, but also extremely efficient at transmitting every irregularity of the road through your body - beating you up after a few hours, accelerating fatigue

I concur. Never had a road bike batter me like a Giant propel. 60 miles over Dartmoor not much fun. Insanely stiff in 2015 - had a loaner from Giant and too unforgiving. Noted over the years the bikes I have seen bought and sold are Propel and Venge. Hammer time. Oddly Propel is Giants best selling bike globally, on looks alone. Suspect Defy would suit 90% of the buying public who could perhaps eek more out of the frame etc.

gweeds

Same with me and the Aeroad.

As much as Aero is everything in the pro world, I suspect that an Ultimate or Endurace are a better bike for 99% of us normal riders.