HELP! Design freewheel and disc brake sprocket adapters ecosystem

[michaelw]

I need information primarily on:

• sprockets
• freewheels
• sprocket freewheel adapters

This is primarily for my son's MX650 razor, but I can see it being of use for others as well. I'll let you guys know if it works but there's a JT sprocket with an 80mm bolt circle pattern that is only about 1mm off from a common freewheel adapter available and if it works I'll share that info I was currently just going to get it mounted then weld the freewheel in place to eliminate that function. I've upgraded to a 1800watt brushless motor on his razor.

We need kindof an eco system that will allow us to use many sprocket options. I hate the current buy this one sprocket that's expensive, buy this other sprocket that's expensive, hassle. I want to design one or two adapters from a freewheel thread or disc brake mount to a popular sprocket bolt hole pattern.

I'm trying to adapt 420 & 428 motorcycle sprockets. I've attached a plethora of picltures of JT sprocket dimensions to satisfy your curiosity.

• focus on threaded adapter? more robust than disc brake adapter? Worth the extra cost? This would need work on a CNC lathe or mill
• focus on disc brake adapter? This can likely be just laser cut from a thick sheet of aluminum and could be very cheap. sub $10/piece at high enough volume. Can be plasma cut, waterjet cut, lasercut, etc. might even be able to make one myself on a CNC router!
• find current off the shelf solutions and piece them together?

I'm not sure the best way to go but I do know that when I want to order a 60 tooth sprocket I want to be able to get one quickly and cheaply. I don't want the hassle of searching the web for hours.

I'd love your help to figure some good ecosystem out, and to spread the knowledge as far and wide as possible

 

[michaelw]

after extensive searching the best 420 sprocket I've found seems to be:

http://www.jtsprockets.com/catalogue/part/JTR1131/
It's available in upto 65 teeth
it has a huge range of options.

The largest 428 sprocket I've found at 69 teeth seems to be:
http://www.jtsprockets.com/catalogue/part/JTR1135/

poor slection in that style tho.

Best selection sems to be:
http://www.jtsprockets.com/catalogue/part/JTR269/

The problem with the 428 sprockets is there doesn't seem to be a 428 motor sprocket for the my1020 motor

 

[markz]

How big a sprocket you want for 428?
https://www.electricscooterparts.com/sprockets428chain.html
https://www.amazon.com/428-sprocket/s?k=428+sprocket
https://chainboss.com/collections/428-sprockets?page=1&sort_by=price-ascending&view=8

after extensive searching the best 420 sprocket I've found seems to be:

http://www.jtsprockets.com/catalogue/part/JTR1131/
It's available in upto 65 teeth
it has a huge range of options.

The largest 428 sprocket I've found at 69 teeth seems to be:
http://www.jtsprockets.com/catalogue/part/JTR1135/

poor slection in that style tho.

Best selection sems to be:
http://www.jtsprockets.com/catalogue/part/JTR269/

The problem with the 428 sprockets is there doesn't seem to be a 428 motor sprocket for the my1020 motor

 

[michaelw]

How big a sprocket you want for 428?
https://www.electricscooterparts.com/sprockets428chain.html
https://www.amazon.com/428-sprocket/s?k=428+sprocket
https://chainboss.com/collections/428-sprockets?page=1&sort_by=price-ascending&view=8

I saw their slection before but the problem is is a 60 tooth costs $77. Not my cup of tea.
For comparison, JT sprockets has a 69 tooth rear for only $24 USD. JTR1135.69

The only thing is it's difficult to find in the US due to it fitting a model that I don't believe was released here.

but a savings of $50 is pretty substantial in my opinion. And what about when I want to tune my drivetrain by buying more sprockets? $60+ a sprocket isn't going to be an appealing option.

 

[spinningmagnets]

The local expert is ES member "LightningRods"