BigAl36

Gottcha....sort of what I figured.

Now a real noob question –
I purchased one Araya 700c ADX 1w and one Araya 700c ADX 2w...with correspondingly different ERD and height/width measurements.
Will there be an impact of using different models of rims? If so, in what way?
Would one rim be better suited for the front vs the rear?

FBinNY 

Are you looking for a thesis on wheel design?

No real impact in using different rims front and rear. People do it every day. As to which to build where, 2 factors to help you decide.

1- stronger/stiffer rim for the rear since that sees rougher service
2- shallower profile to the front because deeper rims make handling more difficult in crosswinds, especially gusty crosswinds.

BigAl36

Not a PHD level thesis....just a masters level.

Good advise.

BigAl36

Time to order -

For the front wheel, Araya 1W has a supposed ERD of 607. I get an average of 609.
With a 3 cross, 12mm brass nips, 295.4 vs 296.4. 296 seems logical.

For the rear, its the 2W, with an ERD of 602 vs my average of 606.
same as above, its 291.5/289.9 vs 293.5/291.8. best guess is 292/290...unsure of what to do here???

RandomTroll

I humbly recommend that you consult the manufacturer's web site.

BigAl36

Believe that was an early stop on the journey. Vintage rims, not much around.

FBinNY 

Gee, should someone come out and lace them up for you?

You made a measurement, At some point you have to trust your own skill set and make a command decision.

Check your work, check the data entered and go with it.

As for the discrepancy between your measurements and the specs, a few possibilities include; a generational difference in the rim profile, an older spec referencing the nipple seat diameter instead of the (nipple slot) ERD, or even a plain old typo.

Consider what's the WORST that could happen. You'll have to buy new spokes for one or even both flanges, and will have wasted the labor of lacing. So, less than 1 hour plus $20.00 or so, which isn't too high a price to pay for the education.

RandomTroll

ARAYA Rims archive from 1960 to 2010

RandomTroll

Hmmmm...

Andrew R Stewart 

We all get testy sometimes. I feel Francis's frustration. I find I have to remind myself about the limitations of this media and that some need more reinforcement then others. Maybe this is why I could never be a school teacher. Andy.

FBinNY 

I wasn't at all frustrated. The maybe we should lace it.... comment was a tongue in cheek response to the continued questions on minor details, and unwillingness to make a decision on his own. The person I was responding to, was the one who made his measurements, ran the calculations, selected the components. He was privy to all the nuances of the process, including exactly how he made those measurements, and I wasn't. So I have less information than he does, and as I said, he has to decide to trust his own work.

At some point birds have to leave the nest and fly. Unfortunately, US culture bolstered by cell phones and the internet, are leading us to a society where every minor decision is made by committee after consultation and deliberation. I'll be in the super market and listen to an obviously educated, affluent adult, maybe a lawyer or doctor pick up a cell phone and call home to find out what size can of stewed tomatoes he's supposed to buy.

I'll bet a beer (crap, a round for all the regulars here) that if we were to poll the regular knowledgeable posters who help on the mechanic forum, we'd find that they all learned by doing, not saying they didn't get help over rough spots, but that they weren't led step by step. Some learned by necessity when stuff broke in the field, or because they couldn't afford to pay others. But they learned to figure things out for themselves because that's how people operated only a few decades ago.

So, yes there's a certain frustration, but it's not with individuals, it's with a culture that doesn't kick people out into the world so they can develop some self confidence and self reliance.

So, my message wasn't intended to be a put down as much as a "you can do this, if only you just try". I might note that I posted that only after I felt that he'd reached the point where it was true.

BigAl36

Hey, I am still in the room!

I have been servicing my own bikes for over 40 years and was attempting to try something outside of my base of knowledge. For some of you, building a set of wheels is muscle memory. For me, its a first. If I wanted someone to build the wheels for me, it would be done by now. I am confident, given enough time, I can get accomplish the task to my personal level of satisfaction.

If I were using rims made in this decade, I would have a higher level of confidence in either trusting the manufacturer or the LBS when it comes to ERD/spoke length. (Wasn't able to get information off of the link to the Araya archives....had everything but ERD)

"So, yes there's a certain frustration, but it's not with individuals, it's with a culture that doesn't kick people out into the world so they can develop some self confidence and self reliance."

I do appreciate advise regarding this wheel build, but I really don't need a life coach.

FBinNY 

You have the rim in hand, so there's no question of needing or trusting anybody else.. It's in your hand, you measured it. Even if you have a published spec, what do you trust more, your own measurement, checked and rechecked, or a published spec that may or may not be right for the rim that you have in your own hand.

I had no intention of being a life coach, but I'd given you all the help possible, and felt you were ready to fly so I tried to kick you out of the nest. You may run into issues during the build and true, but you're at the stage where the only way to confirm the spoke lengths is to buy them and lace the wheel. As I posted earlier the worst that can happen is that you waste some time and $20.00 or so.

RandomTroll

https://sheldonbrown.com/rinard/spocalc.xls has measurements of many Araya ADX rims. Some of Araya's pages have ERDs, not all.

A search of this forum will find many people who build their own wheels who have mis-measured their ERDs. I have. I suspect only Mr FBinNY and a few others can build a wheel in an hour, especially the first time. I take 3-5 and once discovered that my spokes were a mm too long only when finishing, which meant I had to unlace, buy new spokes, do it again. You face the same prospect. Nothing anyone says anywhere can guarantee that you won't have wasted the time and money of building a wheel with wrong-length spokes. I've been in the LBS when a guy brought his bike in to have a flat repaired. We choose how to live our lives.

Don't take people's responses personally. Take what you can use and ignore the rest. There's a lot of great advice here, all of it free, except for the occasional hard feelings.

BigAl36

My points exactly..... I get it may take me hours and I may have to start over and am good with that, I am trying to avoid the mistake of ordering the wrong size, if at all possible.

Bill Kapaun

Just think of it as having spokes for your next build.

FBinNY 

I understood that when I posted earlier. But the ONLY sure way to avoid lacing spokes that are either too long or short is not to build a wheel in the first place. Even with the best information, mistakes happen, and spokes come up off target. It even happens to seasoned builders, the difference is that experienced builders spot the problem early on.

In any case at some point you have to cut or cut bait. You have the best information available in your own measurements and have to rely on it, because nothing is going to change unless you have a trusted friend who can drop by and confirm or correct your work.

So, even though it seems to upset you, I repeat, you can do this if you simply trust yourself and move forward.

Here's one last hint. Spokes generally have 10mm of thread. Look for 12mm nipples with only 7-8mm of thread (sellers don't always know this, but maybe someone here can tell you a brand that conforms to that). With 7-8mm nipple thread, you have 4-5mm latitude in spoke length from 2mm below the top where the 1st thread would show (+1mm if you don't mind a thread showing) to 2-3mm above the top of the nipple before running out of thread. This is only OK with double wall rims.

So, with upto 4-5mm spoke length tolerance, you have a margin for error of 8-10mm in ERD computation, which gives you a decent size target to hit.

So take the old carpenters advice, and measure twice, cut once. You can confirm your own numbers by using 2 different methods.

1- Use 2 spokes threaded to slot and inserted from opposite ends of the rim. Measure from inside the elbow to inside the elbow, and add that to the two spokes to get an ERD.
2- measure overall OD and drop to nipple head, add 1mm to the slot, double and subtract.

Both methods should produce the same value within 1mm (don't forget to use each twice at right angles and average in case the rim is oval). If they do match, consider the odds of getting the same wrong answer by two different methods, and know with confidence that the ERD value is correct.

noglider 

Back in 1978, I worked in a bike shop, and the boss would build wheels by making an educated guess as to length of spoke. Sometimes he was wrong, so he would disassemble the wheel and switch from 3X to 4X or vice versa. Then if that failed, he would try another size. It's not something I recommend, but just bear in mind that life is sometimes like that. In building my wheels, I try to measure as precisely as I can and then hope things work out. I find that spocalc is more precise than I need. Some spokes that "shouldn't" work end up working just fine.

But to put this in perspective, I'm insanely cheap with materials and generous with my time when building my own wheels. Some of my wheels are built from spokes that I've scavenged, and sometimes I even scavenge from more than one wheel. It's pretty disgusting, actually, but I'm still rolling.

BigAl36

Didn't read your follow up after I was done double checking work. From scratch. Started over by re-cutting spokes from method #1 and wound up averaging published numbers for both rims. Spokes ordered..

(I got the 1/8 diameter rod and will prove the work for grins.)

Moving on to finalizing drive train - 52/42 with 13-26 wont get it done for where this will be ridden. The FD has a 14t max ring, RD has 28 max chain wrap and 28t max cog. I want to push both by getting a 13-30 with 48/34. Not worried about the chain wrap as much as getting the 30t to fit. No harm no foul for trying, right.

(This all started out by cleaning the chain. It quickly became a long over-due overhaul. So far there are new/NOS: bars, Brooks, stems and posts, rd/fd, brakes, cranks, hubs and wheels, and a new chain. Most fun you can have with your clothes on!)

BigAl36

Sorry, we are all teacher on here...students as well. This is our school vs one way via YouTube

BigAl36

Laced/unlaced, laced/unlaced, laced/unlaced, laced/got it. Took me a couple times around to get it right. The 10th spoke was not aligned and caused nipples to be too long/short.

speedevil 

For what it's worth, and I know I'm late to the party - I made some measuring sticks out of nipples and spokes.

I hit the spoke threads with a chisel, so that the nipple wouldn't move without some effort, once threaded on. I cut the spoke head off and set the length of both from the bottom of the slot to the end to 230mm.

Put each stick into holes opposite each other and measure the distance between the ends. Move 90 degrees and repeat. Add the distance between the ends + 230mm + 230mm and you have the measured ERD.

Rims are mass-produced, but that doesn't mean they're identical. And, you don't necessarily know how the ERD was measured - it could be to the top of the nipple, it could be to the bottom of the slot, it could be to the eyelet. Granted none of those differences are significant, maybe a mm or two. The "wells" where the eyelets are should be deep enough to handle a couple of mm worth of excess spoke. Of course that's given a good rim tape or veloplugs.

I've only built 3 sets of wheels, which is nothing compared to some folks on this forum. But I wanted to learn how so I read, asked a couple of questions, went ahead and ordered what I thought were the right parts, and built the wheels. They're still rolling and they're still true. Not bad for a wheel-building noob.

ClarkinHawaii

Yeah, Damn Straight!