multiple valve holes on a CR16 rim? Or what are the extra holes?
 

I bought some 24” wheels off Ebay since they were significantly cheaper than I could have built them. New wheels- Deore hubs, Sun CR16 rims, basic spokes for $60 total.
I hadn’t heard of CR16 rims, and based on CR18 rims I figured the width is 16mm which is hardly ideal for a 2.1” MTB tire, but they mount fine so why not.

The rims are drilled for Schrader valves, but the rim has 3 spots(equidistant) also drilled for what looks like Presta valves. The Schrader hold is drilled where it should be(opposite the logo) so its not like that was added later or something.
Also, the double walls are drilled to different diameters on the 3 holes. The inner wall is wider than the outer wall.

Could anyone tell me why(or guess why) there are 3 holes in the rims? And no, they arent spoke holes. Ill close em up so water and junk doesn’t get into the rim, and im sure they will more than support a 24” MTB plus kid, just curious what the deal is.

Here is an image where you can see 2 of the holes in addition to the sticker which is across from the schrader hole.
https://farm1.staticflickr.com/677/3...856b499a_k.jpg

I think those rims were originally meant for wheelchair wheels, and that those are the mounting holes for the hand ring.

Bad programming skills. And then, somebody was snoozing when the robot started doin it's thing.

That is a possibility in which case they are most likely 540 mm bsd, (24 x 1 3/8) not the more common 507 mm.

I picked up a pair of CRT 16's (CRT16II?) 4 years ago that supposedly had been stored for "years" waiting to be built. The labels have partially "fallen off".
These are 622mm, but no extra holes.

This rim would be considered "narrow" for standard 24" "mountain" tires.

Thank you for the suggestion. I figured theybwwrw the standard 24" rim, and double checked. They are 507.
So normal size rim.

Yes, its a narrow rim. 2.1s mounted without issue though and itll be a light rider so i am betting they wont roll laterally from weight/stress.