Originally Posted by
voodoopapa
tommorrow i'm going to run in my go gx-5r motor. i'm currently using fuel with 9% oil (nitro x hp173). do you think i should add some additional castor oil for run in? i was thinking of adding 40 ml to a litre of hp173. would this be beneficial? ive got coolpower fortified castor oil.
Hi Voodoo - nah, we recommend running in on the same fuel you will be racing with. You will be running on the rich side for the first 12 or so tanks anyway, so it will get plenty of lubrication.
The only time we don't recommend this is if you use 30% fuel. We reckon 30% is a little staunch for a brand new tight motor. The higher % nitro raises the compression ratio a little, which is not what you want with a super tight motor. We still add the .2mm shim for run in to lower the compression ratio, so running 30% would be self defeating. You can change up to 30% after .5 of a gallon or so once things are starting to free up and you have removed the extra .2mm shim.