ERD Resource For Wheelbuilders

[Karate Chicken Industries]

I've been on a tear, building wheels lately and can not locate an ERD resource thread on RRB. Please, share your resources and any measurements you may come up with on obscure and/or unlisted rim ERD measurements.

My usual go-to: http://www.tristable.net/bike/erd.html

Adding to that, I just got the caliper out for a 26" mid 60's chrome drop-center middleweight rim at an ERD of 547.

 

[clamdigger]

http://www.kstoerz.com/freespoke/rims/filter

 

[Karate Chicken Industries]

I use this on occasion:

http://velobase.com/ListComponents.aspx?Category=107

 

[Karate Chicken Industries]

Looking for some ERDs and found another source: https://jmoore.me/wheelbuilder/rims/list

 

[Karate Chicken Industries]

Weinmann 2121 26x1.5 and 26x1.75 - ERD 553
Alesa 421 26x1.5 - ERD 553

The Weinmann 2121 and Alesa 421 are essentially the same rim style. The Weinnamm was USA made on both sizes and the Alesa was made in Belguim:

I'm not sure if the following contradicts existing information on the Araya 7X, but it is what I found on them.

Araya 7X 26x1.75 - ERD 549
Araya 7X 26x1.5 - ERD 551

 

[us56456712]

I build wheels where no ERD is available. I’m sure we all do as ancient stuff has no data. I always check against the listed ERD as I have been burned twice by inaccurate ERD from the manufacturer and had to use washers on the nipple heads. Take two spokes with the nipples threaded to the proper depth and clamp them together with a vice grip. Remove and try them in several places. Easy.

 

[Karate Chicken Industries]

I always check against the listed ERD as I have been burned twice by inaccurate ERD from the manufacturer and had to use washers on the nipple heads.

One thing that I think is critical is to use a hoop that you are sure is as round as possible. I had a rim that someone had harvested improperly by not detensioning the wheel evenly.

While I'm still in the midst of my wheel-o-rama, here are a few more ERDs on some ISO 559 rims.

Araya RX-7 26x1.5 ERD 550

Weinmann 422 26x1.5 ERD 556
Weinmann 522 26x1.5 ERD 555

The Weinmann 422s I came up on are in primo shape for polishing and will make for a great pump track bike wheelset on the right build. I trust them more than many double wall MTB rims out there, beefy.

 

[us56456712]

One thing that I think is critical is to use a hoop that you are sure is as round as possible. I had a rim that someone had harvested improperly by not detensioning the wheel evenly.

While I'm still in the midst of my wheel-o-rama, here are a few more ERDs on some ISO 559 rims.

Araya RX-7 26x1.5 ERD 550
View attachment 185959

Weinmann 422 26x1.5 ERD 556
Weinmann 522 26x1.5 ERD 555
View attachment 185960

The Weinmann 422s I came up on are in primo shape for polishing and will make for a great pump track bike wheelset on the right build. I trust them more than many double wall MTB rims out there, beefy.

The rims that had the improper factory ERD for me were new, directly from the company, not a second party vendor. The local bike shop has also infrequently noticed this. The bike shop measures the ERD using some kind of line. They explained it to me, but I have spokes and don’t know what kind of line is stretch proof. We both had to use washers on the rims with the wrong ERD. So, now I check.

 

[Karate Chicken Industries]

I have two new DT Champion 260mm spokes with 12mm nipples that I use to check by putting calipers on the j-bends in the middle of the hoop being measured. One just has to ensure the end of the spoke is threaded all of the way down and flush with the end of the nipple. The builds on some of the recently posted ERDs turned out perfectly. Easy Peasy