Brushes are easy to get.....some of the springs are the hard thing right now.
The KR can be tricky, but its a GREAT motor. Most people gear it wrong and over/under time it.
Try this, 16-18 degrees timing, use the 729/766(both the same compound, just one is standup). The stock spring tension is pretty much is great for most tracks....you can try 767s, but I tend to loosen up the spring tension JUST a tad on more open tracks and increase it just a tad on tighter tracks when I use them. Mainly I stick to the 729s though.
Gearing wise, just gear UP 2-3 teeth from whatever you were using with the D5. That seems to be the ticket with them.
Not sure if you have ever checked out Big Jims forums over at www.rccars.com
, but its a GREAT site for motor tuning tips. Jim can get an ego sometimes, but he knows motors. They have a great KR tuning thread....lots of tips.
And to stay on topic, I should get my new Fukuyama pack for snowbirds.
Did you guys get any new sick packs done? I still need a couple of crazy runtime 4 cell packs.