sdp-si...yikes! Need help picking

[mjp8081]

OK, so I want to build an eMTB, you've probably seen my other posts--thanks

I'm pretty handy, but sdp-si makes me wish I had a mechanical engineering degree. A couple questions:

Can somebody narrow down which belt drive components/specs to look at?--they have tons of different specs. I know I have to do the measurements, I just don't know what to start with

I'm want belt driven but I know chains are more heavy duty. The plastic sprocket looks easier to drill and fit to my MBS hubs (metal)--Belts will work ok, right? Is there a more "heavy duty" belt/sprockets at sdp-si?

Should I reconsider chains?

As always thanks guys for the handholding.

 

[rs4race]

Use their center distance finder if your going with pulleys. I recommend the HTD 5mm. Input your center line spacing and gear ratio. You can change your small pulley, preferably so teeth in mesh isn't red. Then you can click show parts and it will have links to the different pulleys to choose from. There will be different options such as hub, flanges, and belt width.

Make sure the sizes you pick will fit. For example if the small pulley has a 12mm bore it probably wont fit on your motor.

 

[chuttney1]

What rs4race said. Don't worry much about the pulley profile such as HTD or GT2. These are the common pulley profiles this community uses for its shape a curve tooth, but the mechanical aspects are to handle high torque loads depending what your needs are. 5mm HTD will work. Make sure the width of the pulley is adequate. It's better to have a wider belt, but only go as much as you need to. There isn't an more heavy duty part than metal. Generally, metal parts will last longer than plastic and chains will last longer than belt. Some have use plastic pulleys with success.

 

[mjp8081]

Thanks guys--

I will have to click through a few, but man thats cool the way you can render it and download a CAD file

Would you guys go chain or belt? I have a drill press and metal drill bits--should I go metal or polycarbonate?

Now I have to figure out a mount--how should I go about that? Draw up a design? Order aluminum pieces online to bolt together? Is there a site like SDP where I can find generic mounts or brackets and repurpose them?

 

[mjp8081]

One more question: what is the shaft size on the 63mm motors? is it a T indent with set screw? Or do I need the fairlock?

5mm is the belt size?

 

[rs4race]

It is pretty nice that you can download the cad files. If your pretty handy with parts modeling and you have access to a 3d printer you could modify one of their part files and print one out to bolt on. The wheel pulley though, not the one on the motor.

If your not sure about which direction to go I would check out the other mountain board builds on here. You can see what they did as far as chains/belts, motor mounts and how they built everything. I didnt know about this site until after my longboard builds. If I would have been able to look at the builds on this site first I would have nicer boards.

 

[chuttney1]

5mm it the pitch of the pulley or distance between each tooth. A set screw or keyway will work. Press fit works, but do it if you plan to not take the pulley off the motor. The shaft on a 63mm motor is normally an 8mm diameter shaft. Do check...

 

[EBoardBro]

One more question: what is the shaft size on the 63mm motors? is it a T indent with set screw? Or do I need the fairlock?

5mm is the belt size?

5mm is the tooth profile.

Get 6mm+ belt width. Buy extra belts, they inevitably break.

It may vary by Motor, but typically 6mm. You'll want the fairloc hub option and make sure the gears have flanges, or your belt will fall off.

EDIT:8mm shaft NOT 6mm