[AaronR]

Originally Posted by jimmy

Hiya mate, the belts you need are the 369mm ones - part no.53987

I did a lil write up on the big pulley stuff here: http://www.oople.com/rc/photos/cars/501x/bigbelts/

The rear belt will likely be loose from the setting Tamiya gives you in the new sheets. http://www.oople.com/forums/showthread.php?t=6157 Make sure the belts are tight and you should have no issues.

Jimmy has a link to his big belt conversion above, but do not forget to purchase the eccentric belt tensioners also! The standard bearing posts will not work with the new center pulleys.