Madmods Underpowered

[dhdallas]

I originally had my Madmods Scrambler in Florida and it was great; 30mph easy...but Florida is flat as can be. I have it in Pennsylvania now and it is woefully underpowered. At 30 amps & 100% power I have to gear down and pedal hard to get up even moderate hills. It definitely needs a more powerful motor. I have tinkered with all the advanced settings to no avail. I wonder if a Bafang 1500w mid drive would fit? Other than that, I may try a 1000w Bafang geared rear hub motor if the spindle width will work. I wish Sonders would offer a motor upgrade.

 

[m@Robertson]

I originally had my Madmods Scrambler in Florida and it was great; 30mph easy...but Florida is flat as can be. I have it in Pennsylvania now and it is woefully underpowered. At 30 amps & 100% power I have to gear down and pedal hard to get up even moderate hills. It definitely needs a more powerful motor. I have tinkered with all the advanced settings to no avail. I wonder if a Bafang 1500w mid drive would fit? Other than that, I may try a 1000w Bafang geared rear hub motor if the spindle width will work. I wish Sonders would offer a motor upgrade.

Don't waste your time with a hub motor upgrade. The motor change will do nothing., You need an upgraded controller to pump out more amps... but you are already at 30 and if I remember right that bike is something like 95 lbs... Forget improvements with a hub. You are already almost at the peak of where you can go as it is. Mid drive is the only path upward that will give you more hill power. I don't know anyone who has done an HD on one though.

 

[dhdallas]

I thought about upping it to a 52v battery too but I doubt it could be rebuilt into the existing battery pack keeping the same dimensions. There is also the controller to consider going from 48v to 52v. And about the weight; the bike weighs approximately 140 pounds & then you add my 190 pounds & anyone (especially Sondors) would know it would not have enough oomph! Thanks for the input.

 

[m@Robertson]

All controllers running at 52v are just 48v controllers. A 48v system fully charged is 54.6v. A 52v system is 58.8v. Very little difference and pretty much all 52v bikes are running 48v hardware. 52v is about gaining more usable volts (range) and not top speed, as you will drain down into 48v territory pretty quick. But still, you won't get much of a boost from it and you are right it would take a custom build to redo your pack.

 

[dhdallas]

I originally had my Madmods Scrambler in Florida and it was great; 30mph easy...but Florida is flat as can be. I have it in Pennsylvania now and it is woefully underpowered. At 30 amps & 100% power I have to gear down and pedal hard to get up even moderate hills. It definitely needs a more powerful motor. I have tinkered with all the advanced settings to no avail. I wonder if a Bafang 1500w mid drive would fit? Other than that, I may try a 1000w Bafang geared rear hub motor if the spindle width will work. I wish Sonders would offer a motor upgrade.

Update: I got a MadMods when I was in Florida (for the intro price of $1500) & it is great there because of the lack of any hills. Now I am in PA and it struggles with me pedaling hard to barely get up a steep hill. I am going to put in a Bafang BBSHD 1000 watt mid-drive with a 120BB width, leave the rear wheel & original drive system intact with a separate battery for the BBSHD. I can then switch back & forth or maybe even use the existing hub drive to enhance the power of the BBSHD while at the same time reducing the strain on the chain drive of the BBSHD. All the measurements look good & this will be my 3rd Bafang Mid-Drive install so I have the tools & know how. It will need some spacers on the drive side and an offset 44T chainring for decent alignment. I will post some photos of the project & start as soon as the BBSHD kit arrives.

 

[m@Robertson]

The BBSHD could conceivably tear that rear hub apart. After all the drive side motor cover is just a thin casing secured by IIRC 8 M3 bolts. The cassette is secured with small bolts to that motor cover. Even normal hubs have issues when subjected to a 160 Nm mid drive like a BBSHD. I have seen it done before on a Super73-style bike but its strictly a hack. You'd be better off writing this thing off and starting over with a proper mid drive build. Unless you can find a 24" rim and build a wheel in back with maybe some inexpensive but robust Novatec hubs or similar. Something with a steel cassette body, ideally.

 

[dhdallas]

Thanks for the warning. I will check out the hub closer and decide. I never thought of that problem.

 

[dhdallas]

I checked out the hub and it is 1/8" aluminum plate where the spokes attach and the entire hub casing is aluminum. What with the large hub flange, the short spokes, and a smaller chainring than the original, I think I will be ok (famous last words) if I don't do anything really dumb like jump starting with full power or climbing a steep hill in 7th gear! If the hub/wheel fails there are replacement 24x4 rear wheels available with a traditional style hub but wow, are they expensive, $200 & up. Plus I think they only take a freewheel and not a cassette. I will cross my fingers and post my results. I don't like the way any of the 20" wheel moped/bikes feel nor do I want a Fat bike with 26" fat tires. I also have a Giant XTC Seven MTB with a Bafang BBSHD & 26x2.35 tires and it is wicked fast and powerful (but it stays in Florida at my winter house). I have had zero problems in the 3 past years except for replacing a chain and chainring.

Thanks again for the warning.