Upgrading to a BBSHD on a BBS02 based e bike

The limiting factor is the three speed. The heavy duty five speed for cargo bikes will not hold up to an HD. It is designed for Euro builds of motor plus rider. https://www.sturmey-archer.com/en/products/detail/rx-rk5. The three speed in the forest, pulling a deer with the HD will disintegrate. Those dropouts should also be reinforced. I dealt with a cracked dropout this week.
I think the easiest solution might be to limit the BBSHD to 750w with the programming cable?

I’m not looking for high speed or blinding acceleration. With my disability, I need total reliability. That’s why I’m replacing the BBS02.

Of course I realize now that it would have been easier and far cheaper to just keep the BBS02 and get a smaller rear cog for the SA IGH, but Rambo, the hunting e bike company, recommended a larger front sprocket instead if I wanted higher speeds for road use, and said changing out the rear sprocket was more complicated. They didn’t warn me about overheating the BBS02.

After a lot of research I realize that was hogwash - they sold larger front sprockets (more expensive) but not rear cogs (which are cheap), so they recommended the former, not the latter.
 
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By the second time you swap out a rear cog, it is no big deal. I use 16-T on most builds. 20 for elderly in the hills and I always keep a cog selection because as you said, they are inexpensive. Check out this new chain! I am having three shipped for $54 including tax. They will be delivered on this Tuesday.
 
By the second time you swap out a rear cog, it is no big deal. I use 16-T on most builds. 20 for elderly in the hills and I always keep a cog selection because as you said, they are inexpensive. Check out this new chain! I am having three shipped for $54 including tax. They will be delivered on this Tuesday.
I wear this one on Saturday nights when I hit the club

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Warning! Not bike related.
Culturally, when someone is jailed, supposed illegit gains in the form of cash are confiscated. But jewelry is 'personal property' that is retuned upon exit. So, it is a way of maintaining wealth for those who know they may be jailed or are culturally influenced to this effect. King Tut was also influential in the late 70's. I don't know how to Ride like an Egyptian.
 
I think the easiest solution might be to limit the BBSHD to 750w with the programming cable?
What you'll need to do is find the current setting and reduce it from whatever it is (probably 25 or 30) to something a lot less, like ... 15? What that does is reduce the oomph (torque) the BBSHD applies to the rear hub. So you'll lose the benefit of having the BBSHD except for one: The motor will be running well below its rated capacity and essentially will never heat up and probably never wear out. I am a big fan of doing this myself although I do it via other means; mostly related to pedal assist. Leaving full throttle power ability there is just a bomb waiting to go off on you with your hardware so may as well dial it back.
 
What you'll need to do is find the current setting and reduce it from whatever it is (probably 25 or 30) to something a lot less, like ... 15? What that does is reduce the oomph (torque) the BBSHD applies to the rear hub. So you'll lose the benefit of having the BBSHD except for one: The motor will be running well below its rated capacity and essentially will never heat up and probably never wear out. I am a big fan of doing this myself although I do it via other means; mostly related to pedal assist. Leaving full throttle power ability there is just a bomb waiting to go off on you with your hardware so may as well dial it back.
I push 58v 25amps through my SA 3 speed hub and it eats it up. Key was to turn the start current setting all the way down to value 1
 
I push 58v 25amps through my SA 3 speed hub and it eats it up. Key was to turn the start current setting all the way down to value 1
This is something I have near-zero experience with. I did have a 3-speed Shimano IGH on a Luna fixed with a Gates belt, but thats a low-power bike and other than knowing I loved belts from owning that bike, pretty much nothing translates to the rest of the bike world. Only thing is I have read of plenty of these things blowing up the rear hubs. I suspect you have to have all of your ducks in a row in terms of knowing how to ride a mid drive and then you can get a lot more out of it vs. someone who just lights up the throttle. For a beginner... I'd still dial it down until that rider learns the ropes. The consequences of overconfidence could be severe.
 
My adrenaline is beginning to settle. Coming back from all you can eat sushi, I had just finished talking to a friend on a trail and launched my bike when a guy on an electric Cannondale shouted, "Overtaking on your left." I chased him down and beat him on my three-speed. That was fun! It reminds me of when I saw a wild peregrine eat an escaped parakeet.
 

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My adrenaline is beginning to settle. Coming back from all you can eat sushi, I had just finished talking to a friend on a trail and launched my bike when a guy on an electric Cannondale shouted, "Overtaking on your left." I chased him down and beat him on my three-speed. That was fun! It reminds me of when I saw a wild peregrine eat an escaped parakeet.
My adrenaline is beginning to settle. Coming back from all you can eat sushi, I had just finished talking to a friend on a trail and launched my bike when a guy on an electric Cannondale shouted, "Overtaking on your left." I chased him down and beat him on my three-speed. That was fun! It reminds me of when I saw a wild peregrine eat an escaped parakeet.
Too bad the parakeet didn't know any mocking birds... Might not have saved his life but the would have had his back.


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This article claims the three speed SA IGH, specifically the second gear of the SA 3sp, is stronger than any of the other common and affordable multi speed IGHs, due to the construction :

 
Seconds ago I was watching crows divebomb a red tail hawk that was hunting for gophers from the top of a redwood. When they do this the crows almost bark the word Hawk, Hawk. Only 20% of squirrels make it one year. We don't think of them this way but they are killers with razor sharp claws. They eat baby birds.
 
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