I think you've answered your own question.

I'd get the hybrid. Slightly slower, better braking. Why not a 60 front, 90 rear? It will improve stability in crosswinds and be faster.

The second fastest setup that you can get fro Flo is aluminium disc and aluminium front 90...added bonus is that you have brakes.
Thanks Flo !!

I guess I am not clear on how 60-90 is more stable.

90 seems too deep in front. I also do Eagleman every year so didnt want too deep a front wheel.

90 in the front is fast...not deep.
Easy to control...unlike a suicide Hed 3 in bad wind conditions.
A front disc is deep.

A 60 front, 90 rear. The greater surface area in the back will move the center of pressure towards the rear wheel. Think about it this way, you would rather have the forces pushing you sideways acting stronger on the rear wheel and weaker on the front than equal on both (but stronger on the front than the other case). Your front wheel controls steering and the rear isn't​ going anywhere. There was a post recently by Chris, I think, from flo which explained it far better than I did because I'm tired and starting to ramble. It was in a recent wheel discussion and I recommend looking it up. I have a hybrid 90/90 wheelset which I love and have had no issues with, even in a race I did this summer with brutal winds.

Thanks. I think one other "pro" of the 60-60 config was lack of need for valve extenders.

Do you ride your 90-90 setup all the time or just races?

I bought a 60/90 set and rode it at IM Coz last year, will run that again unless I scrape some coins together for a disc. Both aluminum brake track

You do have to think about extenders but I just carry one tube with an extender pre installed. Can be used in either wheel (If on the 60 it may look funny but it will work) and one tube taped under the seat without an extender. If I need it I'll just change it on the road, and if I have gotten two flats the bikes turned to shyte anyway

Coming from a disc / Hed 3 combo and handling is much improved in cross wind

I like the 60/60 combination better than a 60/90 as well. You can train on them while having somewhat normal looking wheels, and also get a wheel cover and have a disc for race day.

Just for races, but I normally throw them on a few weeks out. This is mostly because I do a lot of trainer riding and don't want to shred my nice tires too quickly and because I'm a college kid so if anything happens I can't afford to replace them for a while. However, I would have no issues riding them all the time. They brake better than my training wheels and feel incredibly durable.

appreciate all the feedback! This has been great.

I think I am now leaning towards 60-90 hybrids. I like the braking security especially on a course with lots of fast descents like IMLP and potential for rain. I am not thrilled about the valve extener.

Hi there-

I have a set of 2014 Alu + Carbon 60's and a set of 2016 all Carbon 60's. If you're at all concerned about braking in the wet, the decision is a no-brainer: aluminum rims (hybrid).

damen

Agree. I don't know why there's ever a question. I'd always go 90/90 or 90/Disc in every circumstance. But I am a bigger guy. I've never felt that deep wheels made the bike hard to control.

-Eric

Front 60 is actually faster at low yaw, plus the deeper wheel in the back is better. I'm hoping to get a disc cover soon though, because I'd love to have a 90/disc combo

I've seen that in the Flo aero data, however, it seems to contradict everything I've seen everywhere else with few exceptions.

-E

For those who were looking for the explanation of how a 60/90 is more stable than a 60/60.


A few thoughts on crosswind stability for you.

1. Front wheels cause more stability problems than rear wheels because they have a steering axis (your handlebars/head tube). When wind hits your front wheel it can cause the front wheel to turn, which can cause stability issues, and for lack of better terms, scare you. The depth of your front wheel, and the shape of your front wheel both contribute to the instability. In most cases, the deeper the wheel, the more unstable it becomes. With respect to wheel shape, wheels that produce a high amount of yaw torque (a fancy way of saying the wind causes your handlebars to turn) are also less stable. Some of the most modern wheel designs have taken not only aerodynamics into consideration, but also yaw torque. As an example, our design algorithm included yaw torque as a parameter. This is because we know stability is important, simply because a fast wheel that is nearly impossible to ride, will slow you down because you can't control it.

2. The depth ratio of your front wheel compared to your rear wheel matters when talking about stability. As your rear wheels gets deeper with respect to the front wheel, your center of pressure moves towards the rear end of the bike. To visualize this, imagine you were looking at a picture of yourself riding your bike from the side. If you had to find the center of the "area" you create, that would be your center of pressure. As you create more rear area with a deeper rear wheel, the center of that area moves backwards. As your center of pressure moves backwards, you reduce the force on your front wheel, and in turn increase stability.

I hope that helps,

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Chris Thornham
Co-Founder And Previous Owner Of FLO Cycling

Chris,

I'm trying to decipher what you are saying here with respect to the pressure change from front to rear.
Would you say that your fastest setup for a 30mph+ rider would be the (60 or the 90 carbon) upfront? This is conjunction with the aluminium disc in the rear.
I would like to hear this from you...thank you

The pressure change as I'm discussing it has to do with stability. The answer depends on your wind conditions since our FLO 60 is a hair faster at lower yaw angles. That said, how long are you holding 30+mph, and where are you doing that?

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Chris Thornham
Co-Founder And Previous Owner Of FLO Cycling