Originally Posted by canam73

Maybe for you, so don't buy them. I personally don't care on my training wheels, and when I switch to my heaviest rimmed wheels I don't notice the dramatic difference some others do.

Tell me, Bob, when I am not racing crits how is this going to hurt me? If you wanted to pick on their wheels for having AL nipples or an all aluminum hub driver I'll agree. I consider those to be bigger flaws for typical road riders than 50 extra grams in a rim.

Originally Posted by dmcdam

I don't hear anyone saying the Boyd Altamont wheel set is too heavy - identical weight to the Flo 30 set (Clyde build for both).

Originally Posted by Bob Dopolina

If several people can juggle 4 balls and one can only juggle 3 balls wouldn't you say that those who can juggle 4 balls are better jugglers? Or would you try to find a way to say that the 3 ball juggler is actually superior?

Originally Posted by thirdgenbird

It depends, were they juggling at the same yaw angle?

Originally Posted by canam73

For road racing, I understand your dislike. But the bold section, incorrect.

The XC 279 was originally listed as 472g. My 4 rims were all over 480. And I have seen recent weighing at 497. The XR300s I built were 15 and 20g over list, and I know Psimet has commented that getting the 270 over the 300 to save weight won't always work because he has had them weigh just as much and they list at 20g apart. Fwiw, my A23s are also overweight, but I did have set of Kinlin XR19Ws and some other Velocitys that were spot on. I don't remember if I weighed any of my mavics or HEDs.

Originally Posted by Bob Dopolina

Yes, I am familiar with the brand and the claims on their website.

The weight vs aero work they did is seriously flawed. It assumes a steady effort and does not take into consideration the watts needed to accelerate the wheels hundreds of times during a typical road race or crit. They assume a steady effort like a TT or Tri.

Honestly, there is no reason the make a rim that heavy. Have a look at their direct competitors and ask why all of them manage rims of similar dimensions under 500g.

Originally Posted by canam73

BS. Review your own posts, you trashed the whole brand.

You say you are familiar with them, yet fail to mention that their researches 'flaw' may not be of concert to their primary target?

Originally Posted by dmcdam

I don't hear anyone saying the Boyd Altamont wheel set is too heavy - identical weight to the Flo 30 set (Clyde build for both).

Originally Posted by Bob Dopolina

Tolerences...learn them, live them, love them.

XC-279

472g + 5% = 493.4g
472g - 5% = 446.4g
Possible variation: 47g

Those would be WITHIN TOLERANCE. The 497 grams would be just outside unless the listed weight was actually 480g.

FLO 30

570g + 20% = 684g
570g - 20% = 456g
Possible variation: 228g

So weights are just a crapshoot then? It may not concern you but wildly fluctuating weights set off alarm bells in my addled olde mind.

Originally Posted by Bob Dopolina

The KinLin rims and the alloy rims we make are +/-5g.

Originally Posted by Psimet2001

Breezed through a lot of this so forgive me if I restate, etc.

H plus sons archetype - nice quality control. Cons:heavy for this class, anodized brake surface that will look like crap as it wears. Limited drilling options and inconsistent inventory. Have to buy in the US from "the devil"

A23 - saw someone say they used to be welded in Australia - incorrect. They have never had a welded joint. Aus or US. As for weight variance - they have been fighting extrusion quality since day 1 in the US. They are better than they have been but the quality for me is still way too inconsistent for me to waste my most expensive resource - time building and rebuilding when it's a bad rim. This combined with too many in the field that I have had customers experience extremely fast sidewall wear on...I just avoid it unless it's the only solution. Great weight. Crap shoot quality.

Kinlin xc279 great quality rim like all Kinlins. Cons - Weight. Weight. Weight.

HED c2 - nice rim. Great quality. Nice shot peened finish. Cons: expense, drilling option to only 24, hideous painted permanent graphics, inconsistent inventory

Pacenti sl23 - best rim in this class. Relatively low price, fantastic weight, great strength. Made by Sun Ringle - same as Stans. Seems a lot like the same alloy in Stan's but with much stiffer extrusion shapes. Fairly good quality control. Cons: inventory - they were out from August until a few weeks ago. Latest rims have changed - erd's are different, we have had 2 rim issues we caught during builds in the last week. They assure me this is totally unheard of but I am now hearing stories of spoke pull through in 24 and 32 spoke drillings. Anecdotal (seen 1 picture) at this point. A small handful of customers just can't seem to figure out how to get tires on these. I have hand mounted brand new continental tires on them multiple times to test for myself. Being tubeless friendly they run on the high side. Super wide at 24mm which everyone seems to want to buy regardless of any real solid data from any non-biased test (all tests are biased BTW you just have to figure out the tester's agenda)

Somewhere it was mentioned that I have logged weight discrepancies with Kinlin. Also discussion about weight variance in Flo?

....
1. Yes, I have noted weight variances in every rim that I have ever built with. With Kinlin when we used to build with Xr series people would ask for the 270 in order to drop some weight and yet the standard variance on the 300 and the 270 would give tolerance bands that would indeed overlap. It was common to have a "light" 300 that weighed less than a "heavy" 270.

These variances are a normal part of production. Take a statistics and statistical process control class for more background. Is it because if die wear? Sure. It's also extrusion pressure, temperature, material properties variance, etc. you want to make every rim the exact same weight? Go ahead. Start a rim company and do it yourself. Just throw away everything that is off slightly. Charge your customers for the difference. Have fun with that. Btw this is true of everything ever made by man. The tighter it's controlled the more expensive it was to make.

2. From what I understand about FLo they have chosen to run a aluminum braking surface as a selling point. I understand why they chose to do that- they like the tri market. Tri-market is petrified of full carbon clinchers and will overlook massive negatives like piggish weight rims. Especially if you make any claim regarding any sort of data. As a market they tend to not be as heavily made up of engineers or scientists as regular cycling is and are therefore much less skeptical of data.

A 2 piece rim made up of basically a box section rim with a big carbon tail glued onto it gives you that nice alloy braking surface but leaves you with a tank for a rim. For whatever reason this setup also makes for HUGE variances of the assembled rims. I have personally measured immense swings in weight between identical rims in this technology....whose rims? The old Zipp 404s. They used to be made the exact same way. The rims used to be in the 550-650g range each. Go back and look at the weights they would list on a set of those and you start to realize why their hubs sucked (as light as possible with tiny bearings for weight savings) and why they eventually had to figure out how to make a full carbon clincher that stayed together as all of their competitors had.

The largest discrepancy I have ever weighed was between 2 404 rims. 100g difference between identical rims. These were rims that were used on pcad's build.

Here's the deal - aerodynamics...believe what you want to. Everyone will have data showing that they are the best. If you put them all together and asked an impartial party which is actually best the answer will always....ALWAYS be, "it depends".

Wheel weight - time and time again there has always been a direct correlation between what a rider feels as a fast wheel and it's weight. I personally have always had the best success when I find the right blend of low weight without sacrificing stiffness. Weight is important. Saying aero always trumps it is stretching to make up for something. The only reason any company ever uses carbon is to allow us to build aero depth without adding all the weight that would come with building it that deep in alloy. It's not because we just like carbon, prefer the challenges that the braking poses,etc. it's to save weight. Only. If, in this case, Flo believes that aero trumps weight in all cases then they should build the whole rim in alloy. It would be much cheaper as well. Just sayin.

Sorry. Too long. Gotta go make more donuts.

Originally Posted by canam73

Actually, 9 kJ to be exact. At least per https://www.cyclingpowerlab.com/accel...ndinertia.aspx.

I used a base of an 75kg rider, 7kg bike, 500g front and 700g rear. Then added .5kg to the bike (250g to each wheel). Acceleration was 40-55kph in 5 seconds. Cost difference was 45 Joules per acceleration. 45 x 200 = 9,000 or 9 kJ.

Also equals an additional 8.9 watts during each of those 5 second accelerations (from 909.7 to 918.6) which over the course of a crit would add up to putting out 900+ watts for 16:40 of a 60 minute race. Even if you coasted the rest it would still be over 250 watts average. But this obviously a model, so plug your own numbers in.

Originally Posted by canam73

...Do you have any? Herbie?

Originally Posted by canam73

Your own posts...learn them, live them, love them.

Originally Posted by Bob Dopolina

Typo.

It was supposed to be 5% as my math shows.

Originally Posted by Herbie53

Haven't you had enough?

You bought some heavy, crappy wheels. I'm sure they look nice at the coffee shop, but you are convincing no one that heavy crappy wheels are a good idea for riding fast.

Originally Posted by canam73

Huh. You're talking about the math you presented a day later after I poked a hole in your statement? You see the stupidity in that, don't you?

Originally Posted by Bob Dopolina

No. I have a life and wasn't waiting for your responses. Sorry. And it was a day later for you, maybe, but I live on the other side of the planet and it was still the same day for me: morning vs evening.

Get past my typo and focus on the math and my main point which is about tolerances.

Edit: Jeebus, I am such an idiot sometimes.

I just went back to the FLO site and their tolerance is listed as 20g. I could have sworn it was 20% which was why my mind was completely blown.

20g puts them back in what I would expect but still doesn't account for the weight of the rims. They still seem too heavy.

Originally Posted by canam73

So you understand my comments on personally observed weight discrepancies? Sorry for not recognizing your typo if that's what it was, but when you are blasting one company for a + or - 20 grams it would make more sense to be proud of a 5 gram + or - than a 5% one.

Now, getting back to the effect that weight may have, you may have seen I used your example of an hour crit with 200 accelerations as my model. I would seriously like to know what you think of it.

Originally Posted by Bob Dopolina

Just to finish this bit, ALL produced goods have tolerances. Alloy rims seem to be around the +/- 5% range. I know carbon prepreg hovers around 3%. For the garden variety T-700 stuff most use. There will always be variations so let's just put that to bed.

Regarding the conversation we had in another thread about the amount of energy used with heavier wheels I recall it as being not earth shattering but there were more than a few additional kj needed to do the work.

In an event like a short crit where there is no time to eat or even digest that would be a factor. Sure, I do believe aero trumps weight under most conditions but I can't think of any condition where unnecessary weight was a good thing.

Cyclist the world over have pushed for lower weights for as long as people have raced bikes. There must be a reason for this, non?

Even if we move out of he realm of racing which is the realm (where the aero tumps weight argument was made) and focus on just the enjoyment of riding yer bike, my personal preference is still for lighter weights. I know I can feel the weight on a wheel. I can feel the sluggishness and that extra tonnage spinning around as I corner. It is a factor. To deny it is to be a denier.

Originally Posted by redlude97

You've got to be a shill. Now you are just making stuff up. Boyd/Flo Front 671/725(20H) Rear 890/927(28H). Thats a 91g difference

Originally Posted by canam73

You should retake 1st grade reading. As I stated earlier, I own the kinlins, a23 and a HED. I do not own any FLO products.

No comment on the physics?

Originally Posted by Herbie53

My bad, I have no interest in reading all of your posts and I assumed your passionate defense came from trying to rationalize a poor purchase decision.

Originally Posted by dmcdam

Now you're just not reading what I wrote. I said for me as a clyde at 230lbs, the recommended build from each vendor is 1652g. Flo 725+927 / Boyd 752 + 905.