




It's a sunringle Duroc sd37 rim and these are pictures of the two eyelets opposite of the valve hole near the seam. The rim is supposed to be reinforced there but the layers are starting to separate. I don't know if this is an issue or not
by HaarigerHarri
2 Comments
> these are pictures of **the two eyelets opposite of the valve hole** near the seam. The rim is supposed to be reinforced there but the layers are starting to separate.
There rim *is* reinforced there and that reinforcement *was always separated*. The reinforcement is a “pin”, a flat piece of aluminum that friction-fits into both open ends of the extrusion, but is not otherwise bonded to either of the walls of the extrusion.
I don’t believe I see anything other than the two walls of the extrusion and the pin, all with some swarf from when the holes were drilled. Is there something in the photos you believe I missed? Because I believe these are pinned and welded rims, but the weld is just on the outer face of the extrusion, the pins are never welded.
Hmm interesting.
Are you sure that’s SD37 rim? Search shows this internal structure. Without any additional ribs inside.
This also visible on real photos on some random site, check 5th photo: [https://gbr.grandado.com/products/sunringle-duroc-sd37-27-5-29-inch-dh-bike-tubeless-rims-28-32-hole-mountain-bicycle-aluminum-alloy-disc-29er-welded-seam-rims?variant=UHJvZHVjdFZhcmlhbnQ6Mzc2MTEwODcz](https://gbr.grandado.com/products/sunringle-duroc-sd37-27-5-29-inch-dh-bike-tubeless-rims-28-32-hole-mountain-bicycle-aluminum-alloy-disc-29er-welded-seam-rims?variant=UHJvZHVjdFZhcmlhbnQ6Mzc2MTEwODcz)
https://preview.redd.it/vrks4oadmaig1.jpeg?width=474&format=pjpg&auto=webp&s=844a62c95593551b785befb68a119311ffa48477