In your opinion what would be the ultimate DIY ebike build for 2024?

As some of you know I am huge fan of buying pre-built ebikes on sale. (Pick up one on sale during winter then sell around 16 months later for a very good price. Wash. Rinse. Repeat every year to maximize your ebike experience per dollar spent)

However, sometimes I like to tinker with that idea of building something with DIY parts to see how these processes compare.

So for 2024 I suppose my ultimate DIY build would include the upcoming Grin fat bike hub with 150 x 15mm spacing for use on the front:


This combined with the Bikee Bike lightest mid drive which promises 175mm Q factor when used with 68mm BB. (I am assuming this is the configuration that has both pedal spindles equal length from the frame center line)


So now you are saying....."Woah wait a minute? You want to combine 150mm x 15mm front hub with a 68mm BB shell?" Yes and I can achieve this by using a Jones Frame and Jones fork set (or complete Jones bike) which is optimized and time tested combination using 150mm x 15mm fork, 68mm BB shell mountain frame and 148mm x 12mm thru axle rear hub:


As far as rims go I would go with the Ryde Andra 29er which we have (at large) previously agreed on as the ultimate ebike rim:


As far as batteries go something from Grin would be my first choice.
Buy a used WattWagons, titanium framed (Cross Tour or Ultimate Commuter) w/ innotrace controller. M620 power. 60 - 70lbs and Street Legal Class 3, w/around 120 - 230nm (though mine is set to run up to 2600watts and 260nm in L 5) depending on the mode you're in and an appreciating asset.
Street legal hub drives all overheat and won't climb hills worth a damn.
 
Hmmm i would wonder about the strength of that ebike cassette/freewheel being able to take 1200w of peak power from the lightest.. people have snapped those on pedal power in many a hub.

The 45mm wide motor would be way more than enough power for any ebike unless you're in it to make speed records. You won't be overheating it on hills... i can run 55mph up a ~7% grade with a 35mm leaf... you'd have a bigger motor than that!
WOW !!! You "can run 55mph up a ~7% grade"??? That's literally unbelievable.
How 'bout a snap shot of your display showing you've been 55mph?
Here's mine showing my M620 powered (w/ 260nm) WattWagon hit 56mph - in Sp L5, going downhill. That's w/ a 52T chainring.

20230902_190714[1].jpg 20240817_101247[1].jpg

I had no idea a Leaf was that fast.

FnF
 
WOW !!! You "can run 55mph up a ~7% grade"??? That's literally unbelievable.
How 'bout a snap shot of your display showing you've been 55mph?
Here's mine showing my M620 powered (w/ 260nm) WattWagon hit 56mph - in Sp L5, going downhill. That's w/ a 52T chainring.

View attachment 363198 View attachment 363199

I had no idea a Leaf was that fast.

FnF
The m620 is still the unbeatable ebike motor IMO. Other technology has not matched it yet.
 
Here's what my ultimate build would be today:

$500 Motobecane Fantom 29er.
Why specifically this bike? it has 20mm longer chainstays than most 29ers and will feel more stable at high speed than most bikes as a result.

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Suspension seat post: your pick; i think a Thudbuster LT would be real nice.
Tires: as thick and heavy as they get
Front fork: $200-$300 air fork that's 20mm taller
Battery: 52v 30ah triangle pack from affordableebikes.ca
Motor: Dual Shengyi SX2 ( 13lbs ) or front Shengyi SX2 + lightest mid drive ( 10.5lbs )

1734586108847.png
 
Dual motor, dual suspension, dual seater. Mid drive (3000w) for climbing hills and hub drive (5000w) for cruising.

30ah battery. With dual battery capabilityZ Plenty of room for cargo. Maybe the rear seat area could have fold up basket sides. Big basket on the front. Belt drive would be good but couldn’t really get it to work with a hub drive unless going single speed for the mid drive gearing. Torque sensing.
 
WOW !!! You "can run 55mph up a ~7% grade"??? That's literally unbelievable.
How 'bout a snap shot of your display showing you've been 55mph?
Here's mine showing my M620 powered (w/ 260nm) WattWagon hit 56mph - in Sp L5, going downhill. That's w/ a 52T chainring.

View attachment 363198 View attachment 363199

I had no idea a Leaf was that fast.

FnF
He doesn't say how long the hill is if it's over a 1/4 mile he is melting down.
 
I went up a 7% grade at 50-55mph for a few miles on a leafbike 1.5kw 4T on 72v RC Lipos in ~2014.
The motor was vented though. Today, you would probably use ferrofluid and hubsinks to achieve the same thing.

The motor seems to get happier the more volts you throw at it.
 
Damn. What can that motor do with a regular e-bike battery, say a 25Ah 14s with 50 amp BMS?

I went up a 7% grade at 50-55mph for a few miles on a leafbike 1.5kw 4T on 72v RC Lipos in ~2014.
The motor was vented though. Today, you would probably use ferrofluid and hubsinks to achieve the same thing.

The motor seems to get happier the more volts you throw at it.
 
I was pulling 70-80 amps continuously, and the fun doesn't start on that motor until you put 60A in it, at least the 4T winding of yore.

A battery like that would give you a good experience at 35-40mph top speed using a 5T winding, but probably won't feel like a rocket at 50A.

I never hit the end of what the leaf was capable of because at 50mph, that extra large downhill full suspension frame started to get skittish and indicate that we need a bigger wheelbase. Hitting 60mph on a bike was cool, but i wouldn't do it again ^_^
 
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So which is best for pulling a load? 3.5T or 5T

Keep in mind there is no 3.5T for leaf bike.

Also something to note is that Leaf bike now has both hand wound and machine wound versions of the 1500w Hub and the difference between those two is pretty large in terms of Kv.


"Leaf uses winding machines but also hand-winds some motors, which is why they offer more than just the standard 3T, 4T, and 5T speeds. The hand-wound motors have higher speeds. For example, according to Leaf, a hand-wound 4T motor is 70 rpm faster than a machine-wound one."
 
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I'm trying to answer the question..."can you build a full suspension street bike capable of 35 mph for under a grand?"

It's looking likely, starting with a good quality 20 year old mountain bike off craiglist ($350 ). Add aTSDZ2 kit( $300 shipped) and a 3d printed dock for a Ryobi 40v yard tool battery (dock, $45, battery, used $60). I splurged on a salvaged 3spd SA drum brake laced with 18g ss spokes into a double wall rim (complete, shipped, for $125) A pair of used street tires ($50) left me with room to buy an Ebay cafe racer fairing, to tuck away all the wires and cables. First test hit 29 mph pedaling, I need to drop a tooth or two on the rear sprocket, couldn't pedal any faster.
 
Keep in mind there is no 3.5T for leaf bike.

Also something to note is that Leaf bike now has both hand wound and machine wound versions of the 1500w Hub and the difference between those two is pretty large in terms of Kv.


"Leaf uses winding machines but also hand-winds some motors, which is why they offer more than just the standard 3T, 4T, and 5T speeds. The hand-wound motors have higher speeds. For example, according to Leaf, a hand-wound 4T motor is 70 rpm faster than a machine-wound one."
Speed is great and all but I'm asking which winding is best to get a heavy load moving? 3, 4, 5
 
I wouldn't hold my breath trying to get a tsdz2 equipped bike to do 35mph.
Plugging my conditions into the online calculator (with no allowance for the bikini faring and only giving myself a 250 w output and the tzd only 500 w ) I get 33.1 mph.

If I give myself 350 w peak, and the tzd 720w (18a controller x40 v ) I get 37 mph
 
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So which is best for pulling a load? 3.5T or 5T

The higher turn count is better because the 3.5T will take a super high amp output battery pack.

If you want high torque for pulling, you might want to look at the RH212.
It can actually output ~10% more torque per amp than the 35mm leaf 1.5kw in the low to middle-upper RPM range.
All thanks to the additional poles and diameter.
And a little lighter too.

For high speed and absolute best efficiency, the leaf wins.
For torque, the RH212 wins where it matters most ( low to mid RPM )

A leaf would be great in a <26" wheel though. RH212's torque advantage is more useful in 26" and larger wheels.
 
The higher turn count is better because the 3.5T will take a super high amp output battery pack.

If you want high torque for pulling, you might want to look at the RH212.
It can actually output ~10% more torque per amp than the 35mm leaf 1.5kw in the low to middle-upper RPM range.
All thanks to the additional poles and diameter.
And a little lighter too.

For high speed and absolute best efficiency, the leaf wins.
For torque, the RH212 wins where it matters most ( low to mid RPM )

A leaf would be great in a <26" wheel though. RH212's torque advantage is more useful in 26" and larger wheels.
Personally I'm just learning right now. Far as my future camper trailer build I'm leaning toward geared hub motors which I don't think Leaf makes. But I would think the number of turns would effect a geared hub the same as a direct drive. 26x4 tires I expect.

I must admit I am also considering a DD hub motor custom bike before I build my camper trailer. If I were to build a bike first which is kind of likely what's a good seriously high power high volt motor to use? 26x4+ to a 29 possibly
 
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Geared hub motors can be a great option for high torque.

The problem is that they can't shed much heat, so you can only abuse them for so long. Whereas the DD's massive amount of metal acts as a nice heat reservoir & also sheds heat something like >4x faster.

The ebikes.ca motor simulator is the tool i use to pick the ideal motor for the scenario. In using it for a decade, i know that it models real life very well.
 
I'm planning on pulling a cargo weight of 200 to 300 pounds up some short steep hills with two 1500w dd leaf motors. Fed 40a each at 50v is 4000w total, about 5.5hp. I proceed under the assumption that it might work. Afterall that's 3000 ft-lbs. per second.
 
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