'lightest.bike' 1.7kg 1000w mid drive

@neptronix the 750W is more like a 1000W motor. Feels like a 1000W motor, easily pulls 1000W and 20A @ 52V.

I'm not changing the mounting of my setup. Dual chainring would be my only option out of clown-pedaling purgatory.
 
You know, based on my experience with the 750W, I bet the 1000W Lightest motor at 1200W feels very, very, close to the mighty BBSHD at 1600W.

In my view, because it is already so loud and conspicuous, I should have just gone with the 1000W config. Damn, I wish I did... just to try it.
 
Doesn't need to change much, you just need to find a way to tip it inwards more to clear another 1-2T. I'm looking at your pictures and seeing room to make it contact the frame.

Does it pull that kind of power when climbing? if so, we effectively have the same power give or take 100-200w, so thermal talk is relevant to both of us.
 
nervagon said:
You know, based on my experience with the 750W, I bet the 1000W Lightest motor at 1200W feels very, very, close to the mighty BBSHD at 1600W.

In my view, because it is already so loud and conspicuous, I should have just gone with the 1000W config. Damn, I wish I did... just to try it.
Click to expand...

BBSHD is estimated to have a net efficiency of 80%, it has more rotating weight, an additional gear reduction, larger gears made of lower quality metals probably, therefore more friction, etc etc..
.. now you have substantially more heat and need more metal to shed that heat to.. and that's how we get about the same power @ 3x the weight of this drive.

Makes the BBSHD look like a relic doesn't.

ps - edit - ebikes.ca motor simulator has a simulation of the BBSHD which puts it at 81-82% efficient from 25-30mph.
Motor Simulator - Tools
 
Last edited:
rivers said:
I have a 250 watt Bikee kit installed on a carbon road bike. The motor noise is horrible; much worse than the nervagon video. The sound is completely unacceptable especially for group riding. I am my second plastic gear after being told that the plastic gears had "tolerance problems" and I should try another. I recently installed the new plastic gear, but the noise is just as bad if not worse. I don't know if I have the patience to ride 300 miles in the hope that the noise goes away.
Click to expand...
I actually can’t imagine taking this motor on a group ride with regular bicycles. It’s way too loud for that. Even on an ebike group ride with people I know, it would be the loudest ebike of the group.
 
Here's something funny..

I was watching some ebike show in Australia from a week or two ago, everyone was showing off their little 250w legal mid drives..
The smallest one was maybe 10% smaller than the 1000w lightest... most of them were a bit bigger.

So.. designed around 2020 and still ahead of the competition 4 years later in power density and probably efficiency too.

I'm impressed!
 
neptronix said:
BBSHD is estimated to have a net efficiency of 80%, it has more rotating weight, an additional gear reduction, larger gears made of lower quality metals probably, therefore more friction, etc etc..
.. now you have substantially more heat and need more metal to shed that heat to.. and that's how we get about the same power @ 3x the weight of this drive.

Makes the BBSHD look like a relic doesn't.
Click to expand...
Let’s make a more fair comparison. BBSHD is a reliable pickup truck with cheap replacement parts and thousands of miles of proven record. This is an Italian sports car that only the dealer in Italy can service with several weird quirks.

The Lightest motor is not shit. It is punching way out of it’s weight category, but some things could be better.
 
Pilot Engineer said:
The larger pinion would make the motor spin slower, but the cadence will always be set by the chainring dimension
Click to expand...
Exactly. My point was that because a larger motor pinion would make the motor spin slower, it would make the top speed higher for offroad use. Also the larger motor pinion would slightly raise the chain and give more clearance for a larger chainring. Maybe it would only be suited to 1000W and/or high torque version.
 
Screenshot 2024-03-27 1957121245.png

I would have to give up my HXR easyshift crankset to get PAS with the dual chain setup. I am not a fan of this PAS device. It is all-in-one at the expensive of f*cking up your q-factor. Not good. A place to mount a PAS sensor could have been designed into the drive-side motor mount, and the magnets could be a 1mm-to-2mm thick 24 point disk hidden behind the chainring. This is yuck. I hope a better solution can be spliced into the plug.
 
Man, an external PAS sensor could have been done so awesome, if they had planned ahead. 2 screw holes and a countersink for the sensor to sit in on the drive side motor mount plate. It would have been invisible. And then magnet disk hidden behind the chainring.
 
..this kind of looks like my ~123mm bottom bracket.. IE the smallest size available.. i think this could work only with the next 1-2 steps up of BB width.

Your bottom bracket is pretty uncommon on bikes.. it's possible you could modify a cheap one both physically and electrically.. these things can be found that are thinner than a penny..

1711598486917.png
 
neptronix said:
..this kind of looks like my ~123mm bottom bracket.. IE the smallest size available.. i think this could work only with the next 1-2 steps up of BB width.

Your bottom bracket is pretty uncommon on bikes.. it's possible you could modify a cheap one both physically and electrically.. these things can be found that are thinner than a penny..

View attachment 350038
Click to expand...

I've looked into it and this isn't really a problem for people with 3d printers. Just buy a right-hand PAS kit (like the one above). They seem to be all 3 wire and nearly universal except for the plug. You then 3D print a custom disk and move the magnets from the old disk to your custom disk. My disk would be press-fit onto a 30mm spindle, be 2mm at the base, and have a small lip that snugs against the inner bearing race.

But @Pilot Engineer would need to confirm that the new firmware will allow me to set the PAS pole count.
 
Here's a thought.
Many people with long term mid drive experience don't like sprockets below 14T because they wear too fast.
But we really need these tiny gears to hit the top speed of the motor and a big chainring..

How about using an IGH to achieve the correct gearing and keep that short mount..
IGH will typically have a 19T or 21T sprocket..

This is good because it will raise your chainline and make it so you can fit a bigger sprocket and reduce that pedaling RPM.



Just read this article: Mid Drive Kits, Dump the Derailleur and get an IGH?

Quick summary.. for the power level of the BBSHD they would recommend a 3 speed.. which sounds funny.. but people with BBSHDs end up using 2-3 gears anyway.. and we have that kind of power..


On my kit with a 48T front, 14T rear, and a 33% increase/decrease possible in the gearing, it'd work out like:
Gear 1 - 16mph
Gear 2 - 23.8 mph
Gear 3 - 31.6 mph

If i swap to a 50T front chainring then my top speed is 33.7mph which may be beyond the continuous limit of the motor.. so there's a lot of headroom to move the gearing now (y)

Some people seem to have success with 8 speed IGH and high power drives. The Shimano Alfine 8 would be next on the list of IGH to consider, but is 3x the cost of a 3 speed IGH.
 
nervagon said:
View attachment 350036

I would have to give up my HXR easyshift crankset to get PAS with the dual chain setup. I am not a fan of this PAS device. It is all-in-one at the expensive of f*cking up your q-factor. Not good. A place to mount a PAS sensor could have been designed into the drive-side motor mount, and the magnets could be a 1mm-to-2mm thick 24 point disk hidden behind the chainring. This is yuck. I hope a better solution can be spliced into the plug.
Click to expand...
I wish we could do that. The fact is that on the drive side we have already the freewheel which takes some space. Adding a PAS in there would impact on the Q factor. On the other side that's not happening.
 
neptronix said:
Here's a thought.
Many people with long term mid drive experience don't like sprockets below 14T because they wear too fast.
But we really need these tiny gears to hit the top speed of the motor and a big chainring..

How about using an IGH to achieve the correct gearing and keep that short mount..
IGH will typically have a 19T or 21T sprocket..

This is good because it will raise your chainline and make it so you can fit a bigger sprocket and reduce that pedaling RPM.



Just read this article: Mid Drive Kits, Dump the Derailleur and get an IGH?

Quick summary.. for the power level of the BBSHD they would recommend a 3 speed.. which sounds funny.. but people with BBSHDs end up using 2-3 gears anyway.. and we have that kind of power..


On my kit with a 48T front, 14T rear, and a 33% increase/decrease possible in the gearing, it'd work out like:
Gear 1 - 16mph
Gear 2 - 23.8 mph
Gear 3 - 31.6 mph

If i swap to a 50T front chainring then my top speed is 33.7mph which may be beyond the continuous limit of the motor.. so there's a lot of headroom to move the gearing now (y)

Some people seem to have success with 8 speed IGH and high power drives. The Shimano Alfine 8 would be next on the list of IGH to consider, but is 3x the cost of a 3 speed IGH.
Click to expand...

Sounds fair. Just one suggestion on that. Since the torque sensor is working releasing and freeing some chain length, it's important to put a chain tensioner along with the IGH, in such a way that the chain length variations of the torque sensor are compensated by the tensioner.
 
neptronix said:
Here's a thought.
Many people with long term mid drive experience don't like sprockets below 14T because they wear too fast.
But we really need these tiny gears to hit the top speed of the motor and a big chainring..

How about using an IGH to achieve the correct gearing and keep that short mount..
IGH will typically have a 19T or 21T sprocket..

This is good because it will raise your chainline and make it so you can fit a bigger sprocket and reduce that pedaling RPM.



Just read this article: Mid Drive Kits, Dump the Derailleur and get an IGH?

Quick summary.. for the power level of the BBSHD they would recommend a 3 speed.. which sounds funny.. but people with BBSHDs end up using 2-3 gears anyway.. and we have that kind of power..


On my kit with a 48T front, 14T rear, and a 33% increase/decrease possible in the gearing, it'd work out like:
Gear 1 - 16mph
Gear 2 - 23.8 mph
Gear 3 - 31.6 mph

If i swap to a 50T front chainring then my top speed is 33.7mph which may be beyond the continuous limit of the motor.. so there's a lot of headroom to move the gearing now (y)

Some people seem to have success with 8 speed IGH and high power drives. The Shimano Alfine 8 would be next on the list of IGH to consider, but is 3x the cost of a 3 speed IGH.
Click to expand...
My Rohloff in 14th gear was equivalent to an 11T cog roughly. It gave me plenty of low end gearing, but didn’t expand the upper end.

Box sells the top 4 gears separately for $16.
boxcomponents.com

Box Three Prime 9 Lockring & Cogs 11T, 13T, 15T, 18T black

Lockring & Cogs replacement for Box Three Prime 9 cassettes
boxcomponents.com boxcomponents.com
 
I was expecting better speed. Photon in unrestricted mode will pull up to ~38 mph on throttle or so on my 26" bike with 42/12 gears and 52v battery. That 12 might be 11t but I don't think so. Of course you can't do this for long or it would overheat. And also, of course, that is just throttle because at this speed you can't really do much if anything with the pedals.

nervagon said:
OK, both tasks done.

Lightest top speed throttle only on flat with 29" wheels and 52V battery: 27.3 mph (via GPS) (Edit: mine is the 750W version)

Test ride on wife's GRIN-based torque sensor bike: totally different feel. The pulse...pulse...pulse feeling is not there like it is on the Bikee. Wife's bike has steady and consistent PAS based on effort. Felt very nice actually. Bikee doesn't compare. I don't know why.
Click to expand...
 
raylo32 said:
I was expecting better speed. Photon in unrestricted mode will pull up to ~38 mph on throttle or so on my 26" bike with 42/12 gears and 52v battery. That 12 might be 11t but I don't think so. Of course you can't do this for long or it would overheat. And also, of course, that is just throttle because at this speed you can't really do much if anything with the pedals.
Click to expand...
That 38mph on the photon is unloaded, right? The lightest kit in my most recent testing did 38mph unloaded and 28-29mph real world on flat terrain. I have trouble believing that the photon achieves 38mph real world on throttle. That is hard for me to achieve on a stock BBSHD.
 
No, not unloaded. Bike with me (200 pounds) on the road, without headwind. It will do it in unrestricted mode. Remember, the Photon in unrestricted will have a higher peak power. But it is temperature limited and will throttle back pretty fast if you try this when the motor is already pretty warm. I don't do this often because I am a pedaler and like the torque assist. But it is good for beating traffic sometimes and other specific situations.

nervagon said:
That 38mph on the photon is unloaded, right? The lightest kit in my most recent testing did 38mph unloaded and 28-29mph real world on flat terrain. I have trouble believing that the photon achieves 38mph real world on throttle. That is hard for me to achieve on a stock BBSHD.
Click to expand...
 
Last edited:
raylo32 said:
No, not unloaded. Bike with me (200 pounds) on the road, without headwind. It will do it in unrestricted mode. Remember, the Photon in unrestricted will have a higher peak power. But it is temperature limited and will throttle back pretty fast if you try this when the motor is already pretty warm. I don't do this often because I am a pedaler and like the torque assist. But it is good for beating traffic sometimes and other specific situations.
Click to expand...

Assuming that is on 52V? Can you share the watts/amps being pulled at those speeds?

And semi-related, can you share the cadence/rpm/cycling comfort and your chainring size? My Lightest motor is outpacing me at 52V.
 
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