Finding the right electric e-road motor for a limited road rider.
My first choice would be to continue riding my non-motorized road bike. Alas, it has been difficult to do that for the last few months. I start to suffer at a mere 100 beats per minute at the start of a ride, can sustain no more than 110-120 bpm towards the end, and the riding is not enjoyable. Though the legs and brain want to do more, the heart and lungs won't go along. If it cannot be remedied medically I'll move on to an e-bike, which is why I have been educating myself on the options.
My second choice would be a partial assist e-road bike that approximates the look, ride, feel and fit of my current road bike. In early 2021 that narrows the options, aesthetically and functionally, to Ebikemotion X-35, Fuzua Evation and Specialized SL1.1 propelled e-bikes. The system of choice is not a question of which is better (all seem quite good), but which most closely fits my particular needs. Rather than climbing faster at (my former) non-motorized level of effort, my need would be to reduce effort instead.
Senior citizen that I am, keeping the heart rate below the detrimental threshold only allows me to generate 100-125W on a sustained basis, possibly 150W for brief stretches. That calls for compensating assistance on steep climbs (10-15%) that impose slow speeds and cadences, but require substantial power.
Summarized below is my understanding of the three motors' respective response modes and curves. It is grossly assumed that the US plots would adhere to the pattern of the EU curves at the low end of the range, and that although thresholds can be tweaked, the curves as shown remain indicative of the relative levels of response. Pardon the poor graphics control... far from an online wizard.
- X-35 – Relies on speed to determine the amount of assistance. (The chart is a reconstruction of that EBR member Wilier Trestina obtained from Wilier and posted on the EBR forum.)
Given that my climbing speeds can get down to the 4-6 mph (6-10 km/h) at 40-60 rpm, the X35 motor would boost my 125W by 100-175W at peak assistance.
- Fazua Evation – Relies on cadence and rider power/torque input to determine amount of assistance. The charts were adapted from the Fazua site.
The Evation motor would boost my input by 150-250W based on cadence, fully 250W based on 100W of input.
- Specialized SL1.1 – Relies on cadence, and rider power/torque input up to 100% assistance. The information was taken from sites dedicated to Specialized.
The SL1.1 would boost my 125W with a 100% match of 125W. Stronger riders would take better advantage, up to 240W at 70-100rpm.
The above indicates that e-road bikes that use the Fuzua Evation motor, with its quicker and greater supply of assistance, would work best for me and others stuck in the lower cadence, lower power, lower speed regions of road cycling. The sleeker profiles of the x35 and SL1.1 frames are more appealing, but the necessity for superior low end performance takes precedence. Admittedly, I may not be accounting for some synergistic benefits, not reflected in the curves, that might keep even weaker riders higher up the respective scales. Regardless, any of the three appear to work very well for 200W+, 60+rpm, 15+km/h (uphill) riders.
Posting this with three broad intentions:
- To provide some information to others who may have similar needs
- To invite corrections to misinterpretations that make the information more reliable
- To invite feedback and insights from actual users of these motors, to move the information from the hypothetical/theoretical realm, into the real world.
Thanks to PeterG for his past help, and all you readers for your attention and future help.
That's certainly more than typical cyclists need to handle around the shed. I do agree that there's really not much difference in terms of exercise between a regular bike and an ebike. If anything, the ebike is more versatile because you can opt to make the bike as light or as heavy as you need.
