Mavic A719 ERD
 

Has Anybody built some Mavic A719 700C, 36 spoke rims and know the ERD?
I have been looking and have such a range... 599, 600, 603, 604 and 622. (i don't believe that last one).

I can't get to a bike shop until Saturday to get some spokes to make my own rods but I was really hoping to get the length calculated to get the spokes ordered.

Or does anybody know of a good wheel builder in houston that i could get the measurements and spokes at on Saturday? I wanted to use Wheelsmith 14ga SS spokes.

I've built the A719's into wheels using Shimano Ultegra hubs in a 32H 3X - laced. Wonderful wheels!! Fast. Nimble. Bombproof.

I have also built a set of these, mine were on an XT rear and a SRAM dynohub on the front. I went 36H 3x and I'm also very happy with them (well actually my girlfriend is 'cause it was for her touring bike)

According to my notes the ERD is 603.

According to the Mavic website the ERD is 600mm.
Use double butted spokes. They make for a stronger wheel.
What hub are you using?

incorrect

Don't ever bother looking up erds online, they vary enough to be useless. I don't even trust the ERD from different batches of the same rim i've measured _myself_. Measure erd for the specific rim you're holding in your hands that you're about to build.

When I built my wheels (XT hubs, A719 rim, 36 DB spokes), I used Damon Rinard's spokecalc spreadsheet number of 600.5 mm and double-checked it myself. The spoke lengths worked perfectly. But it would behoove you to check it yourself. The variance won't be more than a mm or two.

Just saying "incorrect" doesn't help the OP at all and is contrary to my own experience.

Yes, actually it does. Learn to read between the lines. Your experience is not enough to know that ERDs that aren't measured yourself are unreliable. When you waste 30 minutes of shop time to build a wheel because you were too lazy to measure the ERD yourself = you're fired.

measure twice, cut once.

specs can change without warning and it's bad methodology to rely on old data when you can collect the data yourself from the final product in your hand.

this is very true for bike wheels where the tolerances for size differences is very slim.

I found some 26" crap wheels so I stole some spokes from one of to make some rods. I measured out 602 to 605 around both rims so I think I will use the 603 ERD number for calculations. Thanks for the replies everyone.

davidad, I am using a Sachs New Success (or an older Suntour Cartridge hub I have if I don't get the sachs shortly)for the rear and an SRAM i-Light dyno hub in the front. These are going on my '85 Cannondale rando bike.

rim rods
 

good work.

The A719 is my favourite modern rim to build with... I always measure the erd myself as too often, the published data is incorrect.

The following spoke-calculator is regarded as the easiest to use and is regarded as highly accurate. But never rely on just one:

http://lenni.info/edd/

I use 600 (as per Mavic's website) and this spoke calculator:

http://www.bikeschool.com/spokes/index.cgi

I round up to the nearest size, could be as much as an extra 1.5mm as calculated on the website, never have any but 1~2 thread sticking out of the nipple. I built several wheels with four different hubs and all the wheels turned out fine.

Operator, old pal, if Mavic can't reproduce ERD within a mm or two on a mass-produced rim like the A719, then they shouldn't be building rims in the first place. Same goes with Velocity, Alex, etc. I don't know what shop/century you live in, but there's such a thing as replaceable parts here in the post-industrial-revolution world I live in. If you were my boss I'd have quit a long time ago, especially with helpful advice like:

"incorrect"

and if I didn't understand why you blurted the previous word:

"read between the lines"

then being slapped with cr*p like:

"your experience is not enough to..." when you have no idea how much experience I actually have.

But, reading some of your previous posts, I realize you're probably just a troll who's never built a wheel in his life, with some socialization problems to boot. A mm or two error in ERD isn't going to waste a single spoke or a single minute of shop time and you know it if you actually have any experience at all with wheelbuilding. If you would just give helpful clear advice without judgment, then every thread you participate in wouldn't turn into a name-calling fest.

Op knows his stuff backwards and forwards... and his advice is generally very sound.

I have found Mavic's published data to be quite reliable as long as you fator in that the number they publish is something they call "Spoke Support Diameter." Add 3mm to this number and you will have ERD. Hey, they're French, they just have to do it different, but they are usually consistent.

Damn that's good! Thank you!

You're quite welcome.

I have used the manufacturer's specs and calculated spoke length with Jobst Brandt's formulas and used DTs and Sheldon Brown's. I haven't had any problems as long as iI pluged in the correct numbers.
So I guess it works brad.

I give correct advice and I don't give a **** how it comes across. You on the other hand seem to want to sugarcoat bad advice. Gee wonder which one is better. Thanks for the worthless contribution to this thread. The bottom line is measure the ERD yourself. You've clearly never built enough wheels to know that a manufacturers stated ERD on their own website can be off enough to render a spoke length calculation wrong. The other option is that you let wheelsets go out the door with short spokes, or spokes that are not up to proper tension because they were too long.

Any other pearls of wisdom to share with us? How about using ERDs scratched on the side of a bathroom stall?

Now look at what you've done! This will, you know, lead to the cataclysmic eruption of Mt. Rainier and the utter destruction of Seattle and Tacoma!

The Horror! The Horror!

Now back to our regularly scheduled program...

To be fair, I've built plenty of Mavic wheels using 717s, 719s, open pros and open sports and used the mavic numbers converted to ERD and it always works out fine.

Before I ran a bike shop I was a design engineer and a manufacturing engineer, and with modern manufacturing processes, especially at a powerhouse like Mavic you can expect that their specs, as long as you have the current ones for the particular model you're using you can expect it to be within acceptable tolerance. If it were a used rim, a boutique rim or something along those lines I'd definitely go with an average of 4 measurements.

LOL, nothing like a wheel building thread to get the ballsacks swinging. Where's that little guy with the popcorn?

Guys, get a room :love:

Hi,

I just built up a Mavic A719 a couple days ago.

I used the calculator http://lenni.info/edd/ and the ERD of 600.5

Turned out great.

I can see the point of measuring yourself; it makes good sense. I can also see the point the engineer made about manufacturing tolerances being quite good.

Anyway, for what it's worth, I don't yet have an ERD measuring device and have used http://lenni.info/edd/ for about 10 wheels (all standard brands, Mavic, Velocity, etc) and have had no troubles.

Happy building...