Glad you figured it out. Personally I'd let him learn without plastic. It can't get broke that way. I had just as much fun riding one with broken plastic growing up. Actually more fun because after it got so bad Dad couldn't tell I'd broke something else.
He made me keep it running good & safe. Some reason he insisted on breaks. That took all the money I could come up with but it also hauled me to my odd jobs that paid for my play. He stopped saying anything about the way it looked after a while.