Removing the speed limit of 20 miles/hr

[mrgold35]

Re: Speedo and Odometer Calculation

3800/23=165.21

165.21 x 25.65= 4237. actual miles Based on an answer found in another forum. But it seems to mnake sense.

Thanks!

Seems like all Radrovers with 26X4 tires would be off around the same 11.5% amount on the low side? Doesn't really matter in the long run since the 1 year warranty is based on time instead of mileage. Most/all maintenance items would also depend on riding conditions (riding style, road conditions, weather, etc...) compared to mileage anyways.

 

[Vince78]

Here you go in simple terms

 

[tomjasz]

Most motors can do some level of over volt. MAC for example can run 36-60V batteries with the right FET version controller.
I'm having issues with reading this thread since I decided to not engage and ignore. What motor does the OP wants to improve speeds on, and what are the controller specs?

 

[AZOldTech]

I just broke brought home my brand-new, 4-thousand-dollar Haibike Sduro Trekking 9.5, was so excited but then this same day, easily getting to 20mph (not very fast for me on any standard geared bike) then the motor not only starts cutting out, as expected, but also feels like it’s intentionally “engine-braking “! I wouldn’t mind if it would just let me do my thing which is well over 20 but this is starting to annoy me already making me start to feel ill with buyer’s remorse.

I would totally agree with your assessment. I normally can do easy 25mph on my road bike without any problem with 30+mph peaks. But on my wife's ebike once I get past the motor max speed (something like 21-23mph - and LCD display speed limiter set to 28mph - which I don't think it does much anyway), there is something that prevents me from upping my cadence cause the ebike feels like it weighs a ton. So it is not only that there is cutoff of power to the motor, but it actually feels that it is intentionally engine braking like you said. Anyone care to explain what is going on? Cause I certainly have the legs to push that baby. But something is keeping me from doing it.

EDIT: Just spoke to the company and this is what they said: "The specific hub motors (for ebikes with max speed 20mph (class 2) have internal gears that are not rated much above 20mph. So when you go above 20mph the motor and the gears themselves act similar to a typical "engine break". If you want to go faster you need to buy a ebike that from the factory have a stated max speed of 28mph (class 3)." BTW, Rad Power does not make any bikes with top speed 28mph (class 3). For those you have to look at Juiced bikes (CrossCurrent S/X) or others.

 

[ebikemom]

26 miles each way is quite a commute! I hope you find a bike that works well for you!

 

[harryS]

Just spoke to the company and this is what they said: "The specific hub motors (for ebikes with max speed 20mph (class 2) have internal gears that are not rated much above 20mph. So when you go above 20mph the motor and the gears themselves act similar to a typical "engine break

Nonsense. The speed restriction is in the controller. My fatbike conversion has the same Bafang G.06 motor as the Radrover. I can reach 28 mph on 48V, and a little more on 52V, However, I normally have mine restricted at 16 mph because (a) it's a high profile bike and I ride on some locales where there is a 16 mph speed limit, and (b) the gearing has me spinning the pedals too fast above 18 mph anyway.

 

[AZOldTech]

Just spoke to the company and this is what they said: "The specific hub motors (for ebikes with max speed 20mph (class 2) have internal gears that are not rated much above 20mph. So when you go above 20mph the motor and the gears themselves act similar to a typical "engine break

Nonsense. The speed restriction is in the controller. My fatbike conversion has the same Bafang G.06 motor as the Radrover. I can reach 28 mph on 48V, and a little more on 52V, However, I normally have mine restricted at 16 mph because (a) it's a high profile bike and I ride on some locales where there is a 16 mph speed limit, and (b) the gearing has me spinning the pedals too fast above 18 mph anyway.

Not based on the manufacturer. Your motor will not last long and its life expectancy will severely compromised. I again double confirmed that the limit has to do with BOTH the motor and the controller. Just changing the controller will not do it. The motor also has to also be rated and sustained capable of 28mph.

 

[harryS]

AZtech, I'm really responding to the inference that a geared motor has an "engine brake" that limits its speed. It's an electrical limiter.

Of course one takes a longevity risk when pushing a bike motor to higher speeds. My fatbike will likely last forever. Barely 60 miles this year. It's just not as much fun as a lightweight e-bike.

 

[AZOldTech]

AZtech, I'm really responding to the inference that a geared motor has an "engine brake" that limits its speed. It's an electrical limiter.

Of course one takes a longevity risk when pushing a bike motor to higher speeds. My fatbike will likely last forever. Barely 60 miles this year. It's just not as much fun as a lightweight e-bike.

But the point was since I don't have a higher Amp controller, of why you can not pedal past the limit especially when you can pedal at much higher speeds on a regular bike. Trying to pedal my way to 25mph felt like is pulling a heavier and heavier load behind me the more close I was getting to 25mph (only got to 24mph before I gave up. I did get to 25.4 one day with a +9mph wind pushing me though). So is it the motor that is not letting you go "free" (after all the hub motors are supposed to have a clutch to let you do that) and go faster by just pedaling alone, or the controller or both? I actually disconnected the controller from powering the motor and the same thing happened over 22mph. So IMO it is the motor.

 

[AHicks]

I agree with the motor clutch idea. I don't know how the motor could be of any influence on how fast you can peddle when equipped with the overriding clutch. By definition, that clutch should not allow that motor to slow the bike (that's why regen won't work with them!)?

Be interesting to see what might happen if you were to kill the power/turn the key off. All the magic stops at that point.

 

[tomjasz]

But the point was since I don't have a higher Amp controller, of why you can not pedal past the limit especially when you can pedal at much higher speeds on a regular bike. Trying to pedal my way to 25mph felt like is pulling a heavier and heavier load behind me the more close I was getting to 25mph (only got to 24mph before I gave up. I did get to 25.4 one day with a +9mph wind pushing me though). So is it the motor that is not letting you go "free" (after all the hub motors are supposed to have a clutch to let you do that) and go faster by just pedaling alone, or the controller or both? I actually disconnected the controller from powering the motor and the same thing happened over 22mph. So IMO it is the motor.

No mention of which motor. The Mac with right CONTROLLER will easily ride better than 25mph.

 

[AZOldTech]

This article describes my thoughts exactly:
No One Gives A Rat’s Ass About Your ‘Street Legal’ Ebike : Build Something Awesome

https://electricbike-blog.com/2016/...r-street-legal-ebike-build-something-awesome/

 

[AZOldTech]

No mention of which motor. The Mac with right CONTROLLER will easily ride better than 25mph.

It's a 48V 500W (peaks at 750W) Bafang BFSWX02 geared hub motor with 9 Mos 48V 500W 18A controller. With all limits removed (set to 28mph), with throttle alone no pedaling and a FULL 48V battery that ebike barely tops at 23mph (about 22.9mph). Once it gets to 80% battery, only 22mph, and at 50-60% 21mph. That bike is rated for top speed of 20mph so I should not complain as it actually does better than 20mph by +10%. The same company has a different class 3 rated ebike with a different eMTB 500W Bafang motor and a 12 Mos 48V 500W 25A controller that's rated at 28mph (so probably can do 30-31mph is my guess if the +10% holds true).

 

[tomjasz]

Sightly larger controller would boost a few MPH. Booth devices an create a bottleneck.

 

[harryS]

Might be a bad clutch on your bike, AZoldtech. Coasting down some of the hills we rode in Colorado last year, my wife was holding to the posted speed limit of 26 mph (on rim brakes) on a little 250W Bafang, while locals on regular bikes flew by us. None of my bikes have the gearing to go that fast under my pedal power, but I have not yet come up against a "wall" as you describe.


.

 

[floyd67]

Might be a bad clutch on your bike, AZoldtech. Coasting down some of the hills we rode in Colorado last year, my wife was holding to the posted speed limit of 26 mph (on rim brakes) on a little 250W Bafang, while locals on regular bikes flew by us. None of my bikes have the gearing to go that fast under my pedal power, but I have not yet come up against a "wall" as you describe.


.

I hit the wall issue as described on a Genze e102 at 18mph.

The ‘clutch’ argument indicating that you can exceed 20 mph going downhill or freewheeling does not address the manufacturer explanation of hub internal gearing because the rider is engaged in the rear hub and pushing the bike on the flat going 18-19 mph with motor PAS support ending.

On the Genze e102, which is torque sensing 350W rear hub PAS, ‘the wall’ is absent at 18-20 mph when in ‘throttle only, no PAS’ (mode 0), perhaps because the motor is still assisting to overcome this internal gear drag felt when PAS cuts out as the bike approaches 20 mph on the flat.

I did not feel this issue on a cruiser E-lux Newport
ebike which has active throttle while in PAS modes and throttle boosting and pedalling together, likely for the same reason. Is the RR setup also either/or PAS or throttle like the Genze?

In any case, PAS without throttle active and a potential rear hub drag ‘wall’ sucks enough to negate the whole eBike advantage indeed. If correct mid-drive designs in the US limited to 20 should not suffer this or anything like it, or dongles will be/are the only way to have a PAS-only design here.

 

[Mike Nowak]

Hey Sai, how much do you want for your used RR and how many miles did you put on it? Thanks

Hi Sai, I'm a new member here also. I have a 2017 Rad City that I commute 20 mile round trips to work on. I've not ridden a Rover yet but my City does a good job getting this 63 year old to work and back five days a week. Have you ridden a new Rad City yet? Just wondering if that bike may be a better fit for you. Good luck and have fun. Mike.