"The real reason they don’t ride P3’s in mass start races has to do with Riis not being an idiot and setting his boys up on sleek looking, but relatively heavy time trial bikes with a mammoth stack of spacers and drop bars… "
Um, I can’t see any reason why a steep setup would handle as well as a slack one. There’s just too much weight on the front wheel, all else equal.
I’ve ridden a 78 degree Scott bike and a 78 degree Cervelo and both were down right spooking when pushed past 80 degrees. Fast downhills and any type of technical riding was downright nerve-wracking. I rode the Cervelo up Mt. Evans one time and the decent was just about the scariest ride I’ve ever had.
Fast forward a year to a technical, switchback descent above Palms Springs on my Yaqui Mariola, that I ride in the 83-85 degree range and I never once thought about the bike, only how much fun the descent was after all that climbing.
If you have a choice, Ves’s bike are incredible.
Chad
P.S. I never went faster on my allegedly more aero Cervelo. I think aero tubes are just marketing.
Exactly, for a steep bike to handle well, all else cannot be equal.
What does the “DE” designation mean and what’s special about it? I thought it was “DL” for “draft legal.”
DE stands for “Dan Empfield”.
Ves’ website is a little out of date-- he must be spending too much time answering our questions and buiding bikes.
Anyway, see the link I gave above for a current description of the standard geometries Ves offers.
Tom
I’ve had three bikes set up steep, and all of them handled the way you described. One with short wheelbase, two with long wheelbase. Longer is better on straights, but they all cornered nicely at high speed. I think that sort of handling is more dependent on how a rider handles his own body weight shifts than what the bike is doing.
ADD: I do have a “no hands” requirement, though. The bike has to handle well riding with no hands. The short wheelbase bike didn’t, but the long ones did/do.
Please forgive my ignorance. What would be considered a short or long wheelbase? Is it in relation to the bike size? Like a 53 Tequilo would have a ____ wheelbase but a 57 would be the opposite?
**Are any frame makers other than Ves making bikes oriented like those along the lines of Dan’s geometry experiement? **
A few days ago I posted that JackRabbit is going to be offering custom bikes in our new store in Manhattan. One of the aspects of the design will be tweaking the geometry, head angle, and fork rake for each rider to get the desired weight distribution and stability. For example, someone who rides with their aerobars relatively low is moving their body pretty far forward, so they put even more weight on the front wheel than a less flexible rider who has their aerobars higher and a little further back.
We’re working on four different designs with our manufacturers: 1)Triathlon bike designed to be ridden in aerobars; 2)Road bike with shorty aerobars; 3)Road bike for the casual rider, and 4)Road bike for the road racer. In category #1, which is what this thread is about, we want the back wheel faired under the rider and the front wheel further forward, which gets more weight onto the back wheel. We’ll also modify the trail to give the front wheel a tendency to keep going straight. At the opposite extreme in category #4, we want the bike to be VERY manuverable, so that it responds to just a slight twitch of the wrist, to handle all the little adjustments that happen in a peleton and to allow the rider to respond to a breakaway – a casual rider without good handling skills would find that bike too twitchy.
I know several other custom bike designers who work with a lot of triathletes do the same thing, so it’s not like it’s a very new idea. But it’s tough to do on a stock bike because the variations in how low people will ride it have a great impact on the balance and handling of the bike.
Lee Silverman
JackRabbit Sports
New York City
I’m no expert, but I have no handling problems on my SoftRide TT7. I am, however, too chicken to ride tough descents in my aerobars, but that would be true for any bike, it is an operator problem.
85 degrees? Wow. How did you go about measuring your seat tube angle? (Just curious).
I’m waiting for the day somebody says they ride at 90. That’s right- a vertical seat tube.
I thought seat tube able was determined by the relationship of the front of the seat to the BB? (At least that is what I read from Dan’s document)
Dave
Greg,
My bike has an 81.5 degree seat tube and I have the seat pushed as far forward on the rails as possible, so I am really just guessing. It’s probably about 83ish. I used to have a Thompson set back flipped forward. I was really forward then, but that didn’t work out very well. I was too scrunched up. And too low in front. Now I just use an American Classic post and push it forward.
Chad
Chad, I assume your current position is the one Ves told you to use in the first place? Interesting that you are higher in the front now.
Do you know what your drop from the top of the seat to your aerobar ellow pads were, and what they are now?
Dave
Remember this is situtation heavily influenced by a few factors beyond the bike, like the stem length, which is effectively the length of the “steering lever”.
If you got a bike with the optimal top tube length for your torso length and the right effective seat angle then you should be using a moderate stem length that will not make your steering adversly stable or adversly responsive.
“We’ll also modify the trail to give the front wheel a tendency to keep going straight.”
probably not a good idea.
I’ve had three bikes set up steep, and all of them handled the way you described. One with short wheelbase, two with long wheelbase. Longer is better on straights, but they all cornered nicely at high speed. I think that sort of handling is more dependent on how a rider handles his own body weight shifts than what the bike is doing.
ADD: I do have a “no hands” requirement, though. The bike has to handle well riding with no hands. The short wheelbase bike didn’t, but the long ones did/do.
Please forgive my ignorance. What would be considered a short or long wheelbase? Is it in relation to the bike size? Like a 53 Tequilo would have a ____ wheelbase but a 57 would be the opposite?
Generally, the bigger the frame “size”, the longer the wheelbase. My 58 QR had a ~102 wheelbase, as does my 55 Yaqui. I had another frame with only a 96 wheelbase (and all of the difference was off the front end), and it had too much weight on the front wheel. It handled ok, but I couldn’t ride with no hands and I always had to make a hard backwards weight shift when I hit the brakes. I did a nose-wheelie for a few yards once going 30 mph. Scared the snot out of me, so I moved to a bigger frame.
And that snot plays hell with handling and braking. (As does s@#*!)
Khai, do you have any opinions on the carbon seat stays and if its worth 400 more?
Dave