Here’s what I’m thinking: When I was a kid, we would use a clothespin + a playing card and attach to the bike, which would make it feel EXACTLY like riding a motorcycle. Machines should drop these kits randomly so you can choose an “upgraded” bicycle with something like a 2% speed increase but the annoying sound attracts more enemies.
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This brings back childhood memories! We used to tie a string from the handlebar to the clothespin so you could change the angle of the pin which would change the noise from the card, like you reving your “motorcycle”
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Strapping something to your bike wheel, so that it generates sound, to imitate motorcycle, is still a thing even today. 
(I wonder why.)
Though, adding additional item to the wheel(s) shouldn’t increase the bike speed. Since it creates additional drag and should instead reduce the bike speed. 
But it would be a good lure for machines with the additional sound it generates.
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I love the idea and even though i agree with @Aesyle’s statement about drag, i think both me and Aesyle should just put a sock in it and enjoy the wroom wroom! 
Another option would be to use a knallert addon-motor (with a roller that transmits the power directly to the front tire, think bottle dynamo, but the opposite… )
I can definitely see this happening; a knallert bike-upgrade schematic requiring a lawnmower-motor (or whatever), the experimental version includes som food-grade nitrus by fitting a cream whipper to the carburettor to create the 6*ludicrous-mode 
Knallert mopeds were quite popular in sweden in the decades before -89 and its construction is pretty much a beefed up bicycle with a addon power-unit consisting of motor, roller and gastank on top of the front wheel.
So it would be lore-friendly to have a motor as an upgrade, along the same lines as adding a scope to a gun.
But still, even though its “wrong” (from a physics standpoint), i do favor the card-in-wheel-idea simply because its so easily recognized from practically everyones childhood.
You dont need to add nor subtract a single item from the “equation” (bike+playing card+clothespin=a whole lotta love!) making it a truly elegant solution.
And as Einstein so clearly stated; everything is relative and the perceived speed does increase by a factor of 5(quadrillions!) when accompanied with the sound generated by the playing-card “engine” 
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