I was in the same boat you're in. I don't consider myself a great bike handler, either.

I went with the 60/90 and JUST ordered my wheelbuilder aero jacket, today.

So, there's that option, also.

If you do any road racing or some tri races that aren't disc legal, get the 90 in the rear as you can get a cover for it and make it 95% as good as a disc anyway. If you don't plan on doing any road races get the disc

may be a dumb question, but other then draft legal races, what other races are discs not legal in?

I don't know the specifics sorry, someone on here will know, I just know some races don't allow discs e.g kona

Some courses that are deemed "too windy" wont allow full disc wheels.

---

2x Deca-Ironman World Cup (10 Ironmans in 10 days), 2x Quintuple Ironman World Cup (5 Ironmans in 5 days), Ultraman, Ultra Marathoner, and I once did an Ironman.

Kona and Cozumel are the only races I know of with a consistent no disc policy. Although other races I am sure reserve the right to ban them depending on conditions on race day

Also, it's not the rear wheel that makes handling more difficult, but the front. In fact a disc actually makes the bike more stable in a cross wind.

I'd get the 90 with a cover to cover all circumstances. 60 front

Please explain how a full disc rear wheel makes a bike more stable in a cross wind..... the front wheel has a greater impact but i do not see how a full disc in the rear would ever make a bike more stable in a cross wind.

---

2x Deca-Ironman World Cup (10 Ironmans in 10 days), 2x Quintuple Ironman World Cup (5 Ironmans in 5 days), Ultraman, Ultra Marathoner, and I once did an Ironman.

My experience running a disc at wildflower during a severe wind warning, and some others agree. I'm not an engineer so I'll leave the whys to others smarter than me.

http://forum.slowtwitch.com/...string=disc;#1642698

 
I'd go 60/90. Do you road bike at all? If you do the 60/90 combo will be nice to use on your road bike as well.

As others have said, I think the 60/90 combo is one of the best all around combos for any triathlete. If I could only own one wheel set, that's what I'd pick. You can race it anywhere, it's great for training, you can put it on a road bike, and a wheel cover gives you the added aero benefit of a disc. If you are at all hesitant with handling, then the front 60 is your best bet.

---

Chris Thornham
Co-Founder And Previous Owner Of FLO Cycling

I've seen many threads about Flo 60's vs 90's and handling in cross winds. In my long distance "A" races, I typically run Zipp 808 and disc. I've also used a pair of Zipp 1080's in a Vegas 70.3. I have never had handling issues with cross winds while using deep rims. I have only rented race wheels in the past and am ready to pull the trigger on purchasing a set of race wheels. I am leaning toward a set of Flo 90's with a disc cover for the rear. Based on information from your website, it appears that the Flo 90 front gains no aero advantage over the 60 at speeds less than 24 mph. I typically race in the 22-24 mph range. While I'd like to race at speeds higher than 24 mph, it's not likely. With that said, do you recommend sticking with the 60 over the 90 in the front? Thanks for you time, energy and helping educate us all on these issues.

If you notice no handling difference and can afford the little bit of weight and cost difference then why not get the 90 instead for if/when you improve beyond the 24 MPH threshold?

I'm not sure where you are seeing the 24mph information but that is older data. We've collected a lot of new data lately and at very low yaw angles (common with higher speeds), the 90 can actually be slower than the 60. If you average the drag savings over a typical ride however, the 90 will be faster. You sound like a very confident bike handler so I wouldn't hesitate recommending the front FLO 90 for you. I think it will be faster.

On another note, if you know where you found that 24mph information I'd like to edit that. I thought I got all of those.

---

Chris Thornham
Co-Founder And Previous Owner Of FLO Cycling

I have hed stinger 6/9s and I definitely notice it when the wind is blowing... im always wondering how people say they dont have handing issues. Are we saying you dont notice at all or just its not blowing all over the road?

The below is in the comments section under FLO aero data, hyperlink to "time savings" (emphasis added):
[Erik,
We use Net Drag Reduction Value (NDRV), which is a weighted average for the full range of yaw angles for the wheel. The FLO 60 has a more aero average then the FLO 90. The reason has to do with the shape we've designed. It surprised us as well. The good thing to know is that the 60 is as aero as the 90 and not the other way around. Width and depth combinations are becoming very important and our wheels prove this. The old rule for v-notch wheels was the deeper you go the faster they are. We know that v-notch shapes are no longer aero in comparison to today's shapes.
All of that being said the FLO 90 as a front wheel has benefit at speeds greater then 24mph+. If you look at the drag data you will see that the FLO 90 is more aero at shallower yaw angles. I hope this makes sense.
Jon
November 13, 2012 at 12:50 PM]

There have been very few times when I have been pushed around on the road by wind. Typically, it would be a wind strong enough to push me around regardless of the wheelset. With that said, I'm a shorter and heavier rider (5'8, 185 lbs) with a lot of upper body strength. As to your question directly, I can't say I've never noticed the wind. But I don't typically have to come out of aero position because of wind.

I don't know the exact physics, but I also feel more stable when using a disc cover and my 404 front, than just 404 front and rear.

I rather have the wind push my rear wheel more than my front...it feels more stable that way rather than having both wheels being pushed the same amount...or god forbid, having your front wheel get pushed more than your rear.

Think of it like riding off road on a CX or mountain bike. If you're going to slide laterally through a dirt or gravel corner, would you rather have both wheels slide the same amount, the rear wheel slide out more than the front, or the front wheel more than the rear? Which scenario is easiest to handle and control?

Thank you! I'm updating this now.

Take care,

---

Chris Thornham
Co-Founder And Previous Owner Of FLO Cycling