Good day.
Current project is a fixing up a beater 1975 DT250B for Vintage Cross Country racing.
And I've made a mistake.
I stripped the front wheel to lace up an alloy rim.
I've done many a lace/true over the years, but goofed on this one.
The brake side spokes are obviously different, 9 inners, 9 outers. No issue there.
On the small diameter hub side...all 18 are inners.
On stripping the wheel I put all 18 in a pile to clean them, assuming they were all the same.
I measured them and they are the same length, at least  to my eye.
And the "bend" at the hub end all look similar.
But apparently they are not...there must be 9 of one type, and 9 of another.
Which makes sense (now...) when you see that one row of 9 is just a bit further out then the other.
When I lace up the new rim...just with the initial threading...the rim is considerably offset.
So...NOW I look at a parts diagram...and I see that there are 2 part numbers for 2 distinct small hub-side spoke sets (of 9 each)

My question: I'll strip it again and lay those 18 small hub side spokes out for a BETTER inspection and sort..
Any advice on how to separate the 2 groups of 9?? Any hints on their difference??
As mentioned...they sure look identical to me. But they're obviously not.

As always, thanks for any advice

Not easy to follow exactly on my computer, pic not that clear.
Interesting it lists 10 of each [should be 9] be good if you get one spare of each but not likely.
So i'm guessing there's about 5mm difference--longer ones would go to the lower holes nearer the axle.
Be easy to get caught out by that & thanks for pointing it out as have one of those wheels in my earlier model 360 'rat bike'.

#6
SPOKE SET, OUTER RIGHT (10 PCS)
product number: 3222518990

#5
SPOKE SET, INNER RIGHT (10 PCS.)
product number: 3222517990

www.cmsnl.com/yamaha-dt250-1975-usa_mode.../partslist/E-01.html

Thanks...I did use the cmsnl link you posted.
Funny how they call one set "outers" when all 18 on the (rider's) right are inners.
But they DO have different part #'s.
I can tell you that the length of the 2 MAY be a bit different...not certainly not by much...certainly less the 1 mm.
Trust me...I stacked them all together up against a straight edge.
To my (aging) eye...they looked to be the same.
But something is different or they would have 1 part # for a set of 18.

Moving on...I did manage to true the rim with the rim centered on the hub, and with the wheel in the forks the rim was centered to the lower fork tubes. Took a bit of fiddling.
But all spoke nipples seem to be turned in about the same...no spokes poking through the nipple.
So...for a XC race bike that will seldom go over 40 mph...I think I'm going to go with it.

Moral of the story: When any of you un-lace one of this type of wheel...keep the 2 groups of right hand inners separate!

I usually see a difference in the head angle. Surprised they would be so similar.

That will be a similar arrangement to the TDR 250 i had. As Steve says in the post above,when you look at the fluted end,one is slightly straighter than the other.