Gearing 12x2 Kr

[GAZ]

I have a 12X2 kr in my xxx4 g + and when i had it geared at 22/92 it came off boiling hot and the com was burnt so i had it skimed and was told to gear it at about 17/92 and now the com seems to be fine but it doesnt seem that punchy and the brushes are only lasting for one meeting is this normal and is my gearing ok as no one else at my club is running one of these motors or cars so i have no one to look to for help except you guys here.

Thanks for any advice given
Gaz

[super__dan]

I have a 12X2 kr in my xxx4 g + and when i had it geared at 22/92 it came off boiling hot and the com was burnt so i had it skimed and was told to gear it at about 17/92 and now the com seems to be fine but it doesnt seem that punchy and the brushes are only lasting for one meeting is this normal and is my gearing ok as no one else at my club is running one of these motors or cars so i have no one to look to for help except you guys here.

Thanks for any advice given
Gaz

In my opinion somewhere in the middle would be right, if I was running a 12 on a 'normal' size track I would be on a 20t pinion on my G+. However KR's are great but require regular maintenance, you should get more than a meeting if you skim regularly.

I used to skim mine very 2 runs and if the motor had not run too hot the brushes could last up to 2 meetings. If you've not got a lathe, then I strongly suggest you get a decent com stick, the green orion one is my favoured on. Though I do have a lathe I use this if I'm in a rush and setup change is more important between runs.

Also filing the trailing edge of the brush gives less overlap and less burning of the com, I could never be bothered but have been told it works.

Dan