Short answer, yes it can go a bit faster but I would recommend the beta motor or a better gearing system then the bike chain.
I have exactly what you are asking about. It was a lyman v2, then I put a filastruder style barrel, filastruder electronics and melt filter. The back is still the wiper motor with the sprocket/chain system. I began to turn up the speed, getting to about 8rpm and then the metal link in the bike chain snapped. Its repaired now but the chain system is now a bit misaligned.
I am still going to experiment with this system. I think with a set of new gears it actually could work but probably at 5-6 rpm. This matches the beta motor so its why I would recommend that. It will just be easier and probably more reliable. I assume I will eventually snap a plastic gear.
Pros of the wiper motor, its silent. The loudest part of that system is the fan. I think theres a reason Lyman moved away from the wiper motor to get better speeds in his v3-v5 extruders though. If you still want to try it send me a message and I will help design gears or something better then the sprocket system.
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