eBike conversion
03-27-21, 01:37 PM
#1
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eBike conversion
I am think to purchase Bafang 750W conversion kit and they come in different crank size in selection (42T, 44T, 46T, 52T). my question is which crank size should I buy for my bike which has (28/38/48 teeth) triple crank ?
03-27-21, 02:39 PM
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Sounds like you're interested in a mid-drive, and the appropriate chainring is a function of intended use, terrain, wind, your weight etc. I started with a 48 on my BBS02 bike, but now incorporate a 30 tooth since all my riding is off road in very steep territory.
03-27-21, 03:25 PM
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On or off-road?
What is the (pedestrian or motor vehicle) traffic pattern that you will be riding in?
Will you be carrying cargo or heavy items on your bike?
Do you use your current 48t chainring most of the time you ride?
What is the (pedestrian or motor vehicle) traffic pattern that you will be riding in?
Will you be carrying cargo or heavy items on your bike?
Do you use your current 48t chainring most of the time you ride?
03-27-21, 08:41 PM
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Thanks for your inputs (things i need to considered). I use most of time on 48T and on bike lane or street traffic. i think i will buy 48T.
03-27-21, 11:45 PM
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I think mine is a 46T and I kept the 14-28 7 speed freewheel on my bike. 26" tires. I just don't care to ride much over 18 mph so I could have gone down to 44T,
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03-29-21, 12:33 PM
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You need to do a bit more research. If you are swapping in a mid drive you will lose your triple crank. 42 tooth cranks work extremely well with a Bafang middrive. They are by far the most popular choice as well.
You don't want the Bafang steel ring however.
You don't want the Bafang steel ring however.
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03-29-21, 01:34 PM
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Weight, speed, terrain & your desired cadence all make a difference. On my single speed road bike I use a 53t chainring (at 100rpm), but I'm kind of an oddball. Everyone's situation will be a little different.
03-29-21, 07:56 PM
#9
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Unless you get creative with the Bafang software you are going to top out at 45kph regardless of which chainring size you choose. 42 tooth is the best for chainline and speed. You can reach full speed on a 29" with 42 tooth up front and 13 tooth in the rear.
