I got these off a old mtb trail bike my mate was going to throw away because I found them unusual and interesting. They have drum brakes, single speed rear sprocket, im unsure but the front wheel hub also looks like a geared hub. What really stood out to me was the rims have no hole for a air valve stem which I never seen. Tyres are solid I'm guessing but they have a psi rating of 50 which is confusing as I'm unsure if solid tyres have a psi rating on them. Any ideas what I got? Are they unusual or rare? Any info would be appreciated. Thanks
by Technical_Pie667