sh**meister

Hi all, first post............ I bought an unmoded chassis off the 'bay' and have done the bush mod, taken the flanges of the bushes down to around the 0.25mm mark, but now when i run it it sounds horrendous. very pronounced gear grumble, and that was running it on my outdoor layout. I am wondering if the worm gear is now riding up the gear wheel. Anyone any ideas?? Ta all meister