Really interesting and I think a viable idea, but I have some reservations. What have you suggested for installation? I am wondering about affixing them into the bars. Is there any other procedure than whacking them into the ends?
I could conceive of a critical failure if one came loose for any reason while riding especially a motorbike! At minimum I think you would need additional all temperature epoxy or pin them through the bars or create a quill type arrangement that's tightened from the end but thats more complicated.
In the end something to consider is the coefficient of expansion btw the two materials. Delrin is probably pretty stable within a wider temp range than steel tubing....If you live in a temperature stable climate you might never be at risk but a wider cold to hot climate could potentially work them loose.
Safety First!
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