How can you not know about the 5000!!!!!!:


https://forum.slowtwitch.com/forum/Slowtwitch_Forums_C1/Triathlon_Forum_F1/Continental_GP5000_test_results_P6797891/?search_string=5000#p6797891






.

---

Once, I was fast. But I got over it.

Very retired, especially when it comes to latest and greatest equipment.

I have 1 bike...used to be a C5, and after getting too much crap from the bike shop guys for riding it...I upgraded the frame to the R3.

---

Brandon Marsh - Website | @BrandonMarshTX | RokaSports | 1stEndurance | ATC Bikeshop |

Well, I just found a pair of hed 6/9 for around 700$ in great condition... I'll follow you advice I think.

On ebay I see that they offer free inteernational shipping:
https://www.ebay.co.uk/...m1438.l2649#shpCntId

I also found some opinions here on ST and they were quite positive. I heard on polish triahlon facebook group few complains about quality but wheels were replaced after informing manufacturer.
I'm from Poland and saw many of RON wheels during triathlons, my friend is riding on 86/disk combo and he is happy with them, many local PROs are using them.

It may be quite cheap option for people from Europe. I'd rather buy Flo's or HED's but tax and duties kill every good deal. Tax is 23% form wheels and shipping price, and some duties are also possible.




I want second pair :D ;)

Pros might be a lot better than me at going uphills, from what I read on their website this combo weights 2.2kg. No way I'm going for such a heavy pair of wheels

you are overthinking weight. you came here asking for advice, and we are telling you that weight does not matter so much. the general agreement on this site is that Aero+Crr > weight.

Unless your course is something like 5% average (estimates range from 4-6%) , the science points toward aero trumping weight. This has been simulated to death with a variety of mathematical models. How many Tri and TT Courses do you have averaging 5%? For reference- most of the mountains you see in the TDF average around 7-8%

Merida has done the math. for a totally flat course, a weight difference of 2kg would gain you a 0.05km/h speed advantage. thats 50 meters for TWO WHOLE KILOS over 120km.

Swiss Side has also done the math. over 120km with an elevation gain of 1200m, riding at 30kph, a 100g weight savings would save you 3 seconds. for a 40k TT, this translates to less than a second per 100g. The aero gain you'd get from that would be far more significant.

My mechanic is a former pro cyclist. According to him, they don't primarily take shallow wheels in the mountains because they 'climb better'. Yes, they climb steeper mountains than most of us, but They take them because the deep wheels get difficult to manage during windy descents in the mountain valleys. So I don't believe the spiel that 'light wheels climb better'

Yes, the right tyre choice has absolutely a larger impact than wheel choice. choosing the right tyre width for the right tyre and tyre pressure matters as well.

I have a RON Wheel. it's decent for the money and have great customer service. Long term durability remains to be seen though.

Shame that VAT takes away many of the good deals available. HED 6/9 combo would not be a bad deal. yes the disc would be faster but not by much, the question is how much is that worth to you.

Hi !

I perfectly understand that total weight does not really matter versus cda/crr. Thats why I will follow the general opinion and go for the hed 6/9 combo I saw near me.
But the weight you're talking about in on the wheels, and 2kg wheels feel like shit. The course is far from 5% average, but you have to take up speed a huge number of times, and I can't imagine pushing those 2.2 kg wheels up to speed even before having to brake again. I mean, that(s a 60mm front wheel that weight 1000g.

The VAT takes away the jet 6 + deals, but the 6/9 combo is a set of second hand wheels near me so I can get them ( and most likely will)

Ah, the myth of rotating weight.


Yes, Adding Mass to the wheel is worse than adding mass to the bike. But the effect is so minuscule that it isn't worth worrying about.


The math has been done for this too. Rotating weight does not in any significant way affect your performance when compared to aerodynamics. It can be shown below.

The Power required to move a wheel will consist of :
power to spin the wheels + power to over come drag + power to overcome rolling resistance.

We assume same tyres, so we neglect power to overcome rolling resistance.

let's assume a 500g wheel weight difference between our deep and shallow rim.

Assume a bike Rider A with light wheels weighing a total of 80kg.
Assume a Bike rider B with a heavier set of wheels weight 80.5kg.

First, let's find the power to spin the wheels
now, using energy equations:
Translational Kinetic Energy = 1/2 * mass* velocity squared
Rotational Kinetic Energy = 1/2 * I * w squared (where I is the second moment of area and w is rotational velocity, and w = v/r where r is the radius of the wheel)

Assuming a WORST CASE scenario where we have a weightless hub and all the weight is on the rim, I = mass of rim *r sqaured.

So the TOTAL Energy required to move a wheel is = 1/2 v^2 *(total mass + Rim mass)

Now let's examine the power required to go from 36kph (which is a typical mortal TT speed) to 53 kph (Pro speed) over, say, 10 seconds. Power = work done (or energy expended) /time.

So we have:
Rider A: Power to accelerate from 36 kph to 53 kph ~ 500 watts
Rider B Power to accelerate from 36 kph to 53 kph ~ 506 watts

Note that this ONLY applies for the 10 seconds you are accelerating. if you are at a steady speed, there is no absolutely no difference in the power to spin the wheels from the wheel weight.

So weight effects of 500g only contribute ~1% of extra power during acceleration.

Now lets look at power to overcome air resistance:

Let us say it takes Rider A 250watts to move at 36kph - this is representative of a real world number.
For Rider A to now move at 53 kph, We know that drag is proportional to the cube of velocity. so, to now go at 53kph, we need approximately (53/36)^3 = 3.17 times the power, which is about 800 watts.


So, the total for rider A power to spin the wheels + power to over come drag = 800 +500 = 1300 watts to accelerate from 36 to 53 kph
Rider B: power to spin the wheels + power to over come drag = 800+506 = 1306 watts to accelerate from 36 to 53 kph.
NOTE WE HAVE NOT YET TAKEN INTO ACCOUNT HOW AERO THE WHEELS ARE YET!

Now for rider B, his wheels are more aero; the question is, how much more? how does is this affected during acceleration? that is a complicated thing to figure out.
We know from a range that the average difference between something like a zipp 404 and a shallow rim is ~ 3-10 watts at 30kph, and between 20-30 watts at 50kph depending on the yaw angle. Now I don't have figures for watts saved at 36 kph and 53 kph, and finding the but lets be lazy and assume somewhere in the average of the two ballpark for the watt savings; say 10-15 watts saved. finding out

So:
Rider A: 1300 watts to accelerate from 36 to 53 kph
Rider B: 1306-10 = 1294 watts to accelerate from 36 to 53 kph.

And note: This is only for 10 seconds of acceleration! Rider B is benefiting from his watt savings all the time! at steady pace of 36 kph, Rider B is enjoying his aero benefit all the time!

Moral of the story: Aero almost always trumps weight, unless you are climbing a 5-6% gradient. If you have to choose between a more aero wheel versus a lighter wheel given a certain budget, always go for more aero.



Here are some links where more involved math is done:

https://www.gribble.org/cycling/power_v_speed.html

http://www.biketechreview.com/reviews/wheels/63-wheel-performance



To quote:
In summary, wheels account for almost 10% of the total power required to race your bike and the dominant factor in wheel performance is aerodynamics. Wheel mass is a second order effect (nearly 10 times less significant) and wheel inertia is a third order effect (nearly 100 times less significant

 
I have a few Vittoria Crono CS tubulars for which the rolling resistance is within ~1 watt of the Corsa Speed clinchers (at 25 mph). Amazingly, they're only 19C (vs 23 for the clinchers) But they are about 12 years old.

It's possible that these newer Crono CS tubs are as good:

https://www.merlincycles.com/...yre-700c-117147.html


but I never tested them.

---

My latest book: "Out of the Melting Pot, Into the Fire" is on sale on Amazon and at other online and local booksellers

They are good, as well as the 24mm version. We found them to be the same speed as Corsa Speeds for Crr, but not as good for puncture protection. Corsa Speeds wear out quicker in terms of Crr though so you need to replace them more often.

---

AeroCoach UK
http://www.aero-coach.co.uk

Well, you all already convinced me to go for a pair of clinchers.
The HED 60/90 I found were just a pair of fake chinese wheels, so I'm still waiting for a good opportunity. In france most manufacturers are still clinging on tubulars, so there is not a lot of choice. And as manufacturers are only selling tubulars, second hand wheels are mostly tubulars too.
I'm waiting for the winter sales to see if I can find a deal on a pair of good wheels that would not be too expensive even If I have to pay the VAT.
I regret no buying the Hed jet 6 + with the previous deal, but maybe the deal will be back one day. If I can't find anything interesting before my next race I'll keep using my old wheels and opt for better tubulars.

Thank you all for your help !

Also I came upon the Xtrem carbon wheels reviewed on TriRig website, are those good ? They are heavy but clincher and rather cheap wheels, that would appear to be a great option ? Dunno if they would fit a scott plasma considering that they appear to be quite wide.