All

Falcon is correct in assuming that neighbors will try to be “ the smart parent “ , and will likely try to “ save” your child. Better to keep it as private as possible, maybe a backyard with a fence would be better. This is incredibly sad for me to write, and I will tell you why…… Bought my child , at 3 years old a 4 wheeler. He was riding on his own, in my ( unfenced ) yard, when a female neighbor was jogging past, and she literally charged at me screaming about child safety , parents setting...

I agree with Marty1028 about the neighbors. It won't be noise that pisses someone off; it will be dust, or the idea that you are allowing your own kid to do something they dislike or feel is too dangerous. In any case, pretty much all kids' playbikes are about the same noise level: quiet.

I know you said you would like to start with the gas bikes first, but i think the electric KTM/Husky e50 models have been on the market long enough that you could score a good deal on a second hand unit. Stock form pretty much all 50s are the same. Id doubt you'd piss off a neighbor. But its 2025 and someone would see your kid just having fun and they'd get mad. I wouldn't really worry about noise.

I have one of these. Takes a beating. https://eboxelectric.com/ebox-2-v2-electric-bikes

best bet is starting him off on a stacyc, graduating to a KTM/GasGas/Husky "E2" model, and then go gas. You're wasting time putting him on a bigger bike than he can ride. I had my kid riding as soon as he could walk on a stacyc with training wheels, tried a PW50 when it was time for a dirtbike before trying anything else and it was too big. Went to the "E2" at 3 years old, he's on an e5 now with a lowering kit and just turned 5. This worked well for us.

Check for burrs and try to look at the threads best you can. This is a weird one.

Chase the threads and get a new bolt/washer.