Building a 1/8 off-road vehicle with belt drive has been a dream project of mine for some time now. At first the idea was a buggy with a custom CF chassis (which I would lay myself), but later it turned out it would be a truggy - a
conversion of the XTM Mammoth ST Pro.
This truggy kit went on sale at Hobby People for clearance and was priced at
$100, a deal which no mortal human being in my position should pass on

. The box sat in my garage for a while until I realized the front/rear bulkheads on my XTM XLB (the Mammoth ST's buggy-sister) would be optimum for fitment of pulleys/belts.
For a random guy like myself, this is a huge undertaking considering a restrictive budget (prototype=production). To achieve the project goals, anything which requires customization or special fitment has to be done by my two hands.
To put things into perspective: there are NO belts/pulleys designed for 1/8 off-road, so wherever there is a pulley on my truck keep in mind that it had to be specially selected and designed
around or modified for the intended purpose.
For starters here is what it takes to turn a specially-selected standard pulley to fit a regular 1/8 off-road diff (a Jammin' diff in this case):


Pulley straight from the manufacturer, with a notch cut in it.


Removing the majority of the pulley's flanges to better fit within the bulkhead (the pulley is pinned to that shaft).

Removal of the pulley hub using a bimetal hole saw with a 1/4" drill bit in the arbor.

Checking fitment of pulley inner diameter to outer diameter of diff cup.