Input needed... 30mph cruise and 40-45mph top speed ebike

bakaneko

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Well, I sold the motorcycle and now I only have my 500W 1.2kWh ebike, which is great and fun but a bit too slow at 22-23 mph top speed, 17 mph cruise, 50 mile+ range. I want to go a bit faster so 40-45 mph top speed, 30 mph cruise, and still 50 miles+ range (at 25-30 mph). I am on a tight budget and maybe some of these requirements can be flexible.

Also, I like to stick with the scooter pack batteries 36V 4.4aH 20A max cont, 35A peak. I mean I don't trust these batteries to do 35A peak so lets just say 20A is peak and I will try to stay around 15A or lower. And, I am still planning to do a 25cc weedwacker generator or DYI friction drive on the rear rack area as a back up.

Here is what I am thinking in terms of a budget build options. Also, I cannot afford the 3000W+ rear hub wheels.

A. Fat tire bike - 3000W SBP Cyclone mid drive kit, iBiky 26" fat tire bike, 72V 24-26aH battery (scooter packs in series). This will cost me about $700. I like this build because there is a free wheel on the mid drive which will allow me to bike without cogging (magnet resistance). However, the issue here is since the batteries are not great I am limited to 20A max which is ~1500W with maybe 2000W burst. Will the bike still be able to get up to 40mph with this limit and a light rider with a windshield. I know 1000W gets you to 30mph but its not linear to 40mph.

B. Scrap fat bike - 1500W rear hub kit, 36V 50-52aH, 1500W step up converter (36V into 52V), new Schalbe Marathon tires, and existing 26" mountain bike. This will cost me about $450. It wont take me to 40mph maybe in a tuck but I should be able to maintain a 30mph cruise. Also, there will be cogging from the magnets and since the step up max is 1500W and the motor probably peaks 2000W I wont get that peak power for 40mph?

C. Super budget - 1000W rear hub kit, 36V 50-52aH, 1500W step up converter, new Schalbe Marathon tires, and existing mountain bike. This will cost me $400. Max speed will be 30 mph but I should be able to use full conversion on the 1500W step up converter.

D. Original hybrid idea - BBR tuning frame, cannibalize iBiky fat tire bike for tires, stem, fork, bars, gears, 750-1000W rear hub motor, no new batteries, 1500W converter, 49cc HS-142F with mounting plate and throttle, and reverse rotation pocket bike gear reduction box. This will cost $800. I don't even know if the BBR Tuning frame can fit a fat tires and a multigear cassette? Here I would use the peddle assist to take off with the strong 1000W rear hub and then open up the throttle on the HS 142-F.

Yeah, I dunno. The biggest concern with best option fat tire bike and cyclone mid drive is the battery wont be strong enough to utilize full power of the engine, which probably peaks at 4000W. So, it might just be a waste. I really like the look of fat tire bikes. It has such a wow factor.

Here is my current bike, the proposed fat bike look (modeled after Ducati Panigale italian flag decals), and a video of some fun on fat tire ebikes. :love: Damn I wish Frankenstein is here to look. :cry:

 

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Street Ryderz

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How much weight in batteries are you carrying?Your first option should get the speed you want but not likely the range as the cyclone tends to draw 12-15 amps at part throttle and around 20 at wot, leaving the 40 amp peak of the controler as a buffer zone for two up acceleration and hills from a stop and such situations that the motor sees extra load.if your batteries cant handle the current draw required every thing will run hot and that will lead to issues as well.I know good batteries are not cheap but they are well worth it in the long run,just in weight and space savings alone is huge.
 

bakaneko

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Each battery pack 36V 16aH weighs about 5.5lbs. So, I was hoping to get like 3x of these so ~17 lbs in total for 72V 24aH. The batteries are on a very small bike frame atm so I don't know if the fat tire bike frame will be bigger. But, if the fat tire bike frame is bigger, I might be able to squeeze in another 4.4aH on the top tube pack and maybe one in the mid pack so in total maybe I can get a 72V 32aH pack made up of the scooter batteries.

Also, because the scooter packs will be in series (72V 4.4 aH) and then put into a parallel array does this greatly increased my max constant current draw. The original pack specifications are

Max. discharging current: 30amp
Max Continuous Discharging Amperage: 20 Amps
Rated Discharging Amperage: 15 Amps

So, in the parrallel configuration I should have much better discharge ratings than the original 36V pack specifications? I think this is the case but I don't know what is the exact change. Here is what I am thinking of in terms of the battery bank design.

Yea, I like Tora and his Juiced Bikes but I am on a tight budget and want to use existing batteries and also make bikes that are tributes to motorcycle and car designers. This one will be Italian flag Ducati.
 

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bike4life

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Each battery pack 36V 16aH weighs about 5.5lbs. So, I was hoping to get like 3x of these so ~17 lbs in total for 72V 24aH. The batteries are on a very small bike frame atm so I don't know if the fat tire bike frame will be bigger. But, if the fat tire bike frame is bigger, I might be able to squeeze in another 4.4aH on the top tube pack and maybe one in the mid pack so in total maybe I can get a 72V 32aH pack made up of the scooter batteries.

Also, because the scooter packs will be in series (72V 4.4 aH) and then put into a parallel array does this greatly increased my max constant current draw. The original pack specifications are

Max. discharging current: 30amp
Max Continuous Discharging Amperage: 20 Amps
Rated Discharging Amperage: 15 Amps

So, in the parrallel configuration I should have much better discharge ratings than the original 36V pack specifications? I think this is the case but I don't know what is the exact change. Here is what I am thinking of in terms of the battery bank design.

Yea, I like Tora and his Juiced Bikes but I am on a tight budget and want to use existing batteries and also make bikes that are tributes to motorcycle and car designers. This one will be Italian flag Ducati.
When batteries or capacitor like things are in parrell, you get better discharge ratings i think, so your correct. Personally, just get a tailgate generator and have that attached to your bike and have that run an ac induction motor. I would doubt those 4000w specs. Thats around 5hp, which is too much juice for a little tiny bike motor. Plus wattage depends on speed and torque. Thats my opinion tho, which might not be the best option for you.
 

LewieBike

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Why not use the Sick Bike Parts 1350 watt motor, it takes a smaller, lighter mount, also by doubling your voltage, you effectively are quadrupling your power consumption with the same drive motor.


You'll need a much bigger speed controller.

So what was once drawing 20 amps will be drawing 80 or more amps. That's welder amperage territory and not something I'd want to have on my E-bike.
 

bakaneko

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Why not use the Sick Bike Parts 1350 watt motor, it takes a smaller, lighter mount, also by doubling your voltage, you effectively are quadrupling your power consumption with the same drive motor.


You'll need a much bigger speed controller.

So what was once drawing 20 amps will be drawing 80 or more amps. That's welder amperage territory and not something I'd want to have on my E-bike.
I dont see that motor on their page? Err, I am following the power convention that if you want to cruise at 30 mph you won't buy a motor that maxes at 30 mph (1000W) but you would get one that max at 40-45 mph (3000W) so that you can comfortably cruise at 30 mph without straining the motor, controller, or batteries. Yeah, I am not keen on such power (close to 2kWh+) in such a small space but I mean if I want 30 mph cruise, 40-45 peak, and 50 mile range this seems to be necessary.
 

LewieBike

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Locally we have a guy who's DIY'd an E-bike using the SBP 3000 watt drive He's over voltage-ing it so it's actually putting out 5000+ watts.

It is lunatic realm fast, but his battery packs are old, recycled DIY laptop mixed bag stuff and I keep expecting to read about him in the local paper having an electrical fire while buzzing around downtown.

The programmable E-controller that SBP and other suppliers carry has a power limiting function. But, you're running gangs of MOSFET's at or above their partial on switching amperage saturation point, when using them on a 40 to 80 percent duty cycle and they will heat up drastically.

If there's not enough heatsink cooling and mass and (or) not enough of them to keep their heating manageable you could burn up your speed control catastrophically.

I've seen this with model electric helicopters being run at higher amps than the controller will handle.
 

bike4life

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Realize that 72x24 is like 1.8kw and 1 gallon of gas has 33.8kw of energy. So yeah. I don't get how you guys say its 5000+watts. That's the equivalent of an aorconditoner or welder or bogged table saw.My DC welder works great off 1800w r u saying your motor draws 3x my welder?? At 72v, that's 70amps of current which will FRY ANY MOTOR. Even at like 140v which is overvolting, it's still a lot of juice, 35a. Am I missing something, there literally now way these ratings are accurate.
 

Street Ryderz

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Realize that 72x24 is like 1.8kw and 1 gallon of gas has 33.8kw of energy. So yeah. I don't get how you guys say its 5000+watts. That's the equivalent of an aorconditoner or welder or bogged table saw.My DC welder works great off 1800w r u saying your motor draws 3x my welder?? At 72v, that's 70amps of current which will FRY ANY MOTOR. Even at like 140v which is overvolting, it's still a lot of juice, 35a. Am I missing something, there literally now way these ratings are accurate.
Totaly accurate their are motors that can draw 100 amp at 102v so 10.2k in watts witch is not that high atm where there are people using 30k in bike's right now,that is with hub motor then their are folks using delta/wye setups that draw huge current and produce serious hp.
 
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