Not sure how you're spinning out at 26mph with 42x10 gearing. My limiter is set at 32mph and I can hit it with a 36x11.The whole "28mph" designation is a bit of a misnomer because without a gear ratio that allows for attaining that speed, on level ground, as a base, it will not be attainable anyway except when there is some gravity involved. Certainly not on any sort of uphill gradient.
I have a Bafang M620 bike that has no restrictor and is capable of 1500w, 52vx30A, with a 42t x 10t gear and it maxes out on level ground spun out at 26mph. Up a paved hillclimb it is capable of the low 20's in the highest assist level. On trails it is restricted to rider ability and common sense.
Then there is the issue of wh/mi usage at speeds over 20 mph where air resistance become a factor? Yesterday I had to go into town to retrieve my van from the mechanic. The route I took was paved with some elevation gain, then a rough trail descent to flat paved road mostly with a tailwind total of 11.7 miles. I didn't dally and made it there in 37 minutes average speed of a bit over 18mph but on the flat paved section in I was pretty much spun out for half the mileage. I ended up using 29 wh/mi.
That Santa Cruz with the Fazua and the other advertised 28mph bikes using EU spec motors will be hard pressed to achieve 28mph much less stay there for any length of time with their small batteries. It is possible to make a road type bike that can but in reality eMTB"s are self restricted to around 20mph no matter what unless as my first post alludes to. If you have to ride much road to get to the trails there is no doubt that running up against a restrictor can be a PITA but that's the way it is.
Your supposed to be riding a bike not clowning around going at those speeds, but a moped. Ffs.The whole "28mph" designation is a bit of a misnomer because without a gear ratio that allows for attaining that speed, on level ground, as a base, it will not be attainable anyway except when there is some gravity involved. Certainly not on any sort of uphill gradient.
I have a Bafang M620 bike that has no restrictor and is capable of 1500w, 52vx30A, with a 42t x 10t gear and it maxes out on level ground spun out at 26mph. Up a paved hillclimb it is capable of the low 20's in the highest assist level. On trails it is restricted to rider ability and common sense.
Then there is the issue of wh/mi usage at speeds over 20 mph where air resistance become a factor? Yesterday I had to go into town to retrieve my van from the mechanic. The route I took was paved with some elevation gain, then a rough trail descent to flat paved road mostly with a tailwind total of 11.7 miles. I didn't dally and made it there in 37 minutes average speed of a bit over 18mph but on the flat paved section in I was pretty much spun out for half the mileage. I ended up using 29 wh/mi.
That Santa Cruz with the Fazua and the other advertised 28mph bikes using EU spec motors will be hard pressed to achieve 28mph much less stay there for any length of time with their small batteries. It is possible to make a road type bike that can but in reality eMTB"s are self restricted to around 20mph no matter what unless as my first post alludes to. If you have to ride much road to get to the trails there is no doubt that running up against a restrictor can be a PITA but that's the way it is.
For Shimano certified OEMs like us here at LaMere Cycles, where we build high end carbon eMTB bikes, we can set the EP801 motors to any speed limit up to 28mph. We ship bikes all over the world and there are different regulations in every country, and different regulations all around the USA even, so we talk to the customer and make sure they know what the rules are on the local trails they will be riding and as long as they are in compliance we sell them what they order.
Using that calculator a 29x2.7 running 34x10 would hit 28mph near enough at 95rpm.Obviously I am wrong and others are right....I'll leave this for reference however.
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