Changing a class 2 to a class 3

[larry_says]

Hi, I'm new to the forum and would like to say hello to everyone first of all
I recently bought a Mukkpet 48v 13ah 750w brushless geared hub motored ebike. I was told it can do 28 mph when I bought it. Well I have found out that it will do 20 - 21 mph tops. Other then me losing 50 lbs. in weight to make it go a bit faster, is there a way to turn it into a class 3? From what I been told class 3 should go 28+ mph. Basically I just want it to go a little bit faster. 28 mph would be great. Any ideas for me? I'm on a budget. Times are hard 8)

 

[E-HP]

Hi, I'm new to the forum and would like to say hello to everyone first of all
I recently bought a Mukkpet 48v 13ah 750w brushless geared hub motored ebike. I was told it can do 28 mph when I bought it. Well I have found out that it will do 20 - 21 mph tops. Other then me losing 50 lbs. in weight to make it go a bit faster, is there a way to turn it into a class 3? From what I been told class 3 should go 28+ mph. Basically I just want it to go a little bit faster. 28 mph would be great. Any ideas for me? I'm on a budget. Times are hard 8)

28mph for class 3 is with pedaling. So are you not able to pedal because of motor resistance (what are the symptoms)? Since it's geared, you should be able to pedal up to 28mph, but without assistance (without the motor fighting you).

 

[larry_says]

Well the bike functions fine and rides well. I weigh 235 lbs. and I know it's most likely a strong factor but I'm thinking the battery may have been cycled to many times and is getting weak. My range is about 25 miles while using throttle and pas together which seems resonable to me. Let's see, what else... I do get resistance at roughly 20 mph and if I pedal real hard I can get it up to 22 mph on flat road. When I'm going downhill it can go about 23 mph with pas, about same on flat road but if I get up to speed then let it coast downhill it will actually go faster coasting vs peddling. What else... Using throttle only it will go roughly 18, 19 mph max. I'm thinking I need a new battery with higher voltage like 52v but I'm not sure what controller and display to use. So maybe a brand new 48v battery with more amp hours then what I have now but I'm not sure if that will make it go a bit faster. I just don't have enough experience to know how to make the bike perform better or the money to learn by trial and error. Anyways, so what you think? I can afford to go 52v, controller and display but I don't know what to get.

 

[amberwolf]

Is it this bike?
https://www.amazon.in/Mukkpet-Electric-Folding-Removable-Commuter/dp/B08RF1KKW4
Some of the details aren't accessible on that page for some reason, but there are a few pertinent ones:

can reach max speed 28mph under e-bike mode and 24 mph under pedal assist mode.14V 13AH Lithium Battery,4-6 hours battery life,suitable kinds of terrains,Longer trips,climb angle achieve 15°

The Net weight is 75lbs.

I would guess "e-bike mode" is the max assist level, but it might be a setting within the display menus instead.

Well the bike functions fine and rides well. I weigh 235 lbs. and I know it's most likely a strong factor but I'm thinking the battery may have been cycled to many times and is getting weak.

This you can test for by watching the voltage sag on either a voltmeter or whatever battery meter the system may have on it's display (if it has one), when accelerating hard or climbing a hill, etc. If there is a lot of sag (voltage drops a lot under load, recovers back to where it was before when load is removed) then the pack is unable to supply the power needed for the load, either because it aging or because it was never capable to start with.

Using throttle only it will go roughly 18, 19 mph max.

If you flip the bike upside down or otherwise get the driven wheel offground, then use throttle or PAS to get wheel to full speed, what speed does it say it is going in each case?

If the max it will go is the same as the on-road speed, the problem is likely a controller limit (which might be changeable in the display menus).

If the max it will go is a lot higher than the on-road speed, the problem may be battery unable to supply enough current (the voltage sag problem noted above), or controller unable to supply enough current to sustain the load (if no significant voltage sag under load).



Regarding hills, what is the worst-case slope and length you have to deal with, and what speed do you need to maintain on them? That plus the system weight (yours plus bike plus anything you carry) can be used to determine approximate power required to do the job, to figure out if what you have *could* do it, and/or figure out what you will have to change.

The http://ebikes.ca/tools/simulator.html can help with this sort of thing, too.

 

[999zip999]

On some controllers there's a Euro speed limiter that happens to be a jst SM 2 pin but it only has one wire it is usually the wire is white if you unplug that wire it could go faster not saying that your battery can take it or your motor could take it without melting up.
I tried to reread my post before I sent it but it's a little too sunny out here
Of course maybe is a big word

 

[larry_says]

Thanks guys for all the input, I really do appreciate it. It turned out to be the battery after all. I'm not sure exactly why it malfunctioned but when i replaced it with a new 48v 20ah battery the problem no longer existed.

Now for the other situation, I wanted to make the bike go a little bit faster and if it goes above 28mph I wont be upset.

Correct me if I'm wrong but this is how I understand this.

If you go sensor less (no hall sensors) providing you have a dual mode controller and remove the display entirely and adding an
on/off button instead then the coding that restricts your speed is removed.

One last thing, if I have a geared motor then the top speed is limited to the motors rpm and the planetary gears ratio.

Have I got my understandings inline with any truth here?
or
Is it wiser to just go with a bigger battery, controller and display. Maybe even an off-road controller and display?

EDIT: As it is right now my bike will do 25 to 26mph. It still seems slow to me. I just want it to go a little bit faster then the average e-bike so I can be the Boss. lol.
Any input is appreciated. Thanks guys

 

[E-HP]

I’d suggest enjoying the bike as is and have fun. You need to go up in voltage to achieve higher speeds, but you’ll never be the boss on that thing no matter what you do.

 

[docw009]

You never said which Mukpet bike you bought, but I think they only sell a 20" fat tire folder and a 26" fat tire, I believe either will run 24-26 mph on 48V, throttle only. They're all basically similar generic geared motors and probably 20A controllers. Upright seating, no aerodynamics. inaccurate speedometers and cheap tires. I've owned both types of ebikes, and that's my experience, although I bought good tires.

Consider smooth tires if you have fat tires. Better for pavement anyway and quieter, Probably faster, I don't think it's worth further changes.

Get a second 26" regular bike with good brakes. Put a cheapo Voilamart direct drive motor on it with a capable battery, You could probably even use the ones you own with another cradle, I hear those do over 30 mph routinely.

Used to be, those 1000W kits were as low as $150 USD, Thought about it, but for me it would be a one trick bike, so I never tried them,

 

[Chalo]

I had a bike of that brand in my stand a few days ago. The mechanical disc brakes were so bad (not worn out or broken, just crappy) that there wasn't anything I could do to make them work acceptably. I ordered the very cheapest replacement calipers I could get, like $16 full retail per caliper. They were a massive upgrade from original equipment.

Such shoddy me-too chumpcycles were designed to resemble e-bikes (they don't especially resemble bicycles), but they're definitely not set up to do the work of being an e-bike. By the time you set one in good running order, you'll have spent more on it than whatever you saved by not getting a better bike to begin with, and lots more than if you built your own.

If you can squeeze 25 or 26 mph out of your bike, count yourself lucky. I advise against going that fast with the original brakes.

 

[99t4]

Now for the other situation, I wanted to make the bike go a little bit faster and if it goes above 28mph I wont be upset.

Important Question: What were the results from the test amberwolf requested you do in post #4 above?

If you flip the bike upside down or otherwise get the driven wheel offground, then use throttle or PAS to get wheel to full speed, what speed does it say it is going in each case?

If the max it will go is the same as the on-road speed, the problem is likely a controller limit (which might be changeable in the display menus).

 

[larry_says]

I'm sorry I left you guys hanging like that. It's been a while since i been online here. To answer the last question, there is no telling what my speedometer reads when I just let the tire spin. My display screen went black on me shortly after my rear axle spun out a quarter turn in the dropout.
So at this point my original dilemmas are no longer of concern. Today I have newer dilemmas. I bought a used hub motor RMG60750 and I bought a new display and controller. And I'm trying to make it a true class 3 but this controller or display gives me no option to turn off its cruise control. So I'm wanting to buy something different.
So today I would like to ask what controller & display would be best for a throttle-less class 3 pedal-assist only set up for my newly bought used RMG60750 motor?

 

[larry_says]

You never said which Mukpet bike you bought, but I think they only sell a 20" fat tire folder and a 26" fat tire, I believe either will run 24-26 mph on 48V, throttle only. They're all basically similar generic geared motors and probably 20A controllers. Upright seating, no aerodynamics. inaccurate speedometers and cheap tires. I've owned both types of ebikes, and that's my experience, although I bought good tires.

Consider smooth tires if you have fat tires. Better for pavement anyway and quieter, Probably faster, I don't think it's worth further changes.

Get a second 26" regular bike with good brakes. Put a cheapo Voilamart direct drive motor on it with a capable battery, You could probably even use the ones you own with another cradle, I hear those do over 30 mph routinely.

Used to be, those 1000W kits were as low as $150 USD, Thought about it, but for me it would be a one trick bike, so I never tried them,

Its a mukkpet suburban 26" fat tire

 

[E-HP]

The Phaserunner has a good reputation in that power range and is very flexible.

Phaserunner - Grin Products - Product Info

The Phaserunner was our first major controller partnership with ASI to bring their high performance field-oriented controller platform into a form factor and connector standard that worked well with ebike systems. It can support up to 72V nominal batteries and works well with systems running...

ebikes.ca

 

[larry_says]

I’d suggest enjoying the bike as is and have fun. You need to go up in voltage to achieve higher speeds, but you’ll never be the boss on that thing no matter what you do.

Oh really now? Seeing is beleiving.

 

[E-HP]

Why did you go with the G60 if you already have a 750W hub motor?
750W, G60 at 48V with a 20A controller, looks like 22.2 mph. With a 40A controller, 22.3mph. Is that enough to be the boss?

 

[larry_says]

Why did you go with the G60 if you already have a 750W hub motor?
750W, G60 at 48V with a 20A controller, looks like 22.2 mph. With a 40A controller, 22.3mph. Is that enough to be the boss?

View attachment 367592

I'm running a fardriver with field weakening. The used motor was affordable and it has way less miles on it. Also have a total of 82Ah's

 

[larry_says]

Anyways all is well for me now. Thank you all for your time. Sorry if I missed some questions along the way. Take care