I would like to custom build a crankset which would like the one I have on my ebike, but with more teeth. My current chainring is 52T, and I would like to go up to 58T. What I have is a four bolt, crankset, with two chain guards. Unfortunately, I am told that it is one piece, forged together somehow, and cannot be taken apart. So, I need to make one myself from parts found in ebay and aliexpress. What I was thinking was buying a 58T chainring, two chainguards, and a 130BCD crankset. Does this make sense? Would it all fit? Are chainrings all metal? Should I worry about plastik? Would it be about the thickness?
Why would I want one? My ebike reaches 30KMH, at which speed I am spinning out... I have 6 gear shimano, but with the motor, I never use anything but the highest gear. I would like at times go faster, pedal assisting the motor, so as to gain few KMH.
The objective is a relatively cheap speed + exercise combination.
I figured out the math that in adding 11.5% (58/52 - 1) to the number of teeth, I could be spinning out at 33 km/h. This is not very much, but it may be cost-effective vs the alternative of changing the motor and controller.
My rear wheel is 20", so the relatively large and not so common chainring does make sense.