Alesa 913



I've got a couple of Alesa 913 rims that have been hanging in my garage
for 8+ years. Anyone know where I can find ERD dimensions for that
rim? I don't trust my measurements.
 
Hi Volden
You don't seem too sure of your wheel measuring. If you care to read
it, I'd be happy to give you my procedure for measuring ERD.
It's not really hard to measure much more accurately than any published
ERDs. Here's how I do it:
(This is harder to read than do. I'm pointing all this out to help
insure accurately measured ERDs.)
Take 2 spokes of same length. Screw on 2 identical nipples so that the
spoke is even w/ bottom of nipple.
Measure both spokes from bottom of nipple to where the shoulder of
spoke head to spoke joins the spoke, w/ a mm rule (U can use inches &
convert. It's just easier to use mms) If different, even them up.
(Again, don't have to, just ez'er)
Install spokes & nipples in opposite holes. {Make absolutely certain
they are opposite each other. Count holes. It's EZ to miss. I know ;-)}
Do the following on a reasonably flat surface.
Measure the distance between the spoke heads; inside one "J" to the
opposite "J", w/ the nipple pulled into the rim spoke holes. I use
spokes that are shorter that the radius of the ERD. Place a digital
caliper @ each junction & move the caliper & spokes back & fourth to
obtain the smallest dimension, while putting light pressure on the
caliper & spokes to pull the nipples in. Not so much as to possibly
damage the caliper.
Add both spoke lengths & the minimum caliper reading.
Divide the rim into 3 nearly equal sections (6 pie segments) & measure
for a total of 3 times. Add your measured ERDs & divide by 3.
You should have much more accurate #s that any table can give you.
Note:
If one of the 3 ERD is quit a bit different from the other 2, throw it
out & remeasure. Keep measuring until you get consistent ERDs from each
set of spoke holes. It?s best to identify each measured hole set w/ a
sharpie, so you can go back to it.
If U don?t have a set of calipers, just use an mm rule, or inch rule as
the case may be.
Try to pull or push any looseness out of the spokes.
And sweep the heads to the minimum distance.
Take more that 1 or 2 ERD measurements, because many rims are not
perfectly round.
The spokes don?t have to be the identical length, (Again, don?t have
to, just ez?er)
U don?t have to, but the nipples should be the same brand as U are
going to use to build the wheel.
Don?t forget the most critical dimension in the entire spoke length
formula is the ERD
Happy Holidays, John