I've been running my X - 5 squared almost every weekend since last October. Its been running great. I'm running the front brace across the white bulkhead (info/tech page
), this bulkhead "mod" (really just trimming it so it fits better, info
), and the caster block screws (info
- recommended for both Losi 4wheelers as well).
Not a modification but just a change - going to the larger spurs we've come out with in the last year or so can really help open up the gearing for brushless motors. Going to the 108 tooth or 110 tooth spur gear can let you use not-quite-so-small pinions while maintaining the necessary super-low drive ratios.
Something I've been noticing over the last few months to help the driveline is to take a few minutes and make sure the belt is running centered on the drive and idler pulleys. That is, once the car is together and has electroncis and everything, turn it on, give it some throttle, then turn it back off and carefully take off the top cover. If the belt is running to one side of the drive pulley or the other, adjust the shims on the slipper shaft appropriately - so like if the belt is running on the left of the center pulley (toward the spur gear) take a shim out from between the slipper plate and the left bearing and put it on the right side of the shaft. That will move the drive pulley slightly to the left, and get the belt in the center of the gear. Do the same for the idler pulley (probably easier to do with the bottom cover off).
I'm running SMC lipo's in my X - 5, squeezed in along the right side of the car behind the servo, but unfortunately don't have a camera so I can't snap any pictures. I'll figure out something...
It can take a little bit of careful fiddling to get the driveline working just right, but once it does the X - 5 is just ballistic.