electricfun
New Member
Hello. Need some buying advice.
I have a stromer st1 platinum step thru and I need to replace the drive train (minus the derailluers). I know I need a 9 speed cassette and chain and 3x crankset.
My question is what kind of free wheel do I need? 9 speed I know that but do I need a specific kind for ebike?
Also when it comes to the bb, I know this is a 73 x 138 square taper BB. My question is does the new BB need to be this exact size? I'm aware the "square tapered" part refers to how to the crank fits to the BB, so thus not completely relevant. I'm assuming the 73 number matters more, so say if I get a 73 x 122.5 would this work?
My current crankset is 50x 39 x30
This is the one I'm considering buying http://www.chainreactioncycles.com/ca/en/shimano-tiagra-4703-triple-10-speed-crankset/rp-prod137766
I have a stromer st1 platinum step thru and I need to replace the drive train (minus the derailluers). I know I need a 9 speed cassette and chain and 3x crankset.
My question is what kind of free wheel do I need? 9 speed I know that but do I need a specific kind for ebike?
Also when it comes to the bb, I know this is a 73 x 138 square taper BB. My question is does the new BB need to be this exact size? I'm aware the "square tapered" part refers to how to the crank fits to the BB, so thus not completely relevant. I'm assuming the 73 number matters more, so say if I get a 73 x 122.5 would this work?
My current crankset is 50x 39 x30
This is the one I'm considering buying http://www.chainreactioncycles.com/ca/en/shimano-tiagra-4703-triple-10-speed-crankset/rp-prod137766
