Motor pulley questions

Hello, I was planning on buying pulleys from [belting online] (, and they offer multiples options but I don’t know wich one to take ? for example 18T 15mm wide I choose a 8mm bore because of my motor and then what ? Should I consider a keyway ? Will they just pierce the pulley or actually give a pulley ? Should I consider grubscrews and if yes what size and how many ? What’s the best : keyway or grubscrew ?

Do you have some other EU pulley sellers ? Thanks.

What motor do you have ?, does it have a keyed shaft ?,…if not get a 3-4mm grub screw on the motor gear’s hub .

Single motor,then go for 15mm wide gears, motor gears are usually between 14-16T, wheel gears can vary depending on wheel size ,…80mm wheel 36T gear is good.

I was looking at these on eBay. They look nice but 9mm wide I think?

I have a SK3 192kv comming soon. I don’t think it has a keyed shaft so you suggest me to put a grubscrew ? Do I have to dremel a small hole where the screw goes ?

Just dremel a flat spot on the shaft around 5mm long so you can move the gear a li

ttle if needed to align the 2 pulleys

Alright perfectn thanks a lot I’ll do that, so no need for keyways

Considering my 36T and 40T wheel pulleys, I’ll buy 15T 15mm, 16T 15mm and 18T 15mm motor pulleys that I will fix on the shaft using grubscrews. What size screws should I buy ? guessing that the grubscrew holes will be in the hub. @Randyc1 are you sure 3-4mm M4 grubscrew will be enough ?

what size wheel you have ??

if you buy from onlinbelting buy metal Motor gear , you will have option when choosing gear , choose Grub screw , the biggest that can fit in the hub, probably 4mm, When installing Gear on flatspotted shaft , do a test fit to know excactly where on the shaft, the Gear needs to go ,… then apply (High Strength Loctite on SHAFT), Insert gear and tighten Grub screw with a small amount of (Med Strength Loctite on Grub screw), Firmy but do not over tighten to damage threads. Mine is done like this , it has never moved !

I might need a small puller to remove Gear if needed though. Applying heat on grub screw if you need to remove will also help.

I’d recommend with a keyway + dual flange + grub screws which fit M4 if possible.

For a regular motor,

You can always shave/file a D shape and fit a key in too. They key does help transmit all the force.

If you don’t do the D shape/key. I’d recommend to use socket cap M3 or M4 bolts as they are more durable than the set screws.