I think you may have found my problem if you ar right... I am using a shift arm from a kit that I picked up cheap... came with gears, bearings, shafts, pinion adn shift arm for less than the spur gears alone... It hasn't been right since I used it... I think it may have the wrong spring rate in there... I don't know the color of the spring, but the spare springs it came with are all silver.I think I'll take it apart and take a look... I still have the original which worked well so it may go back in there.. I haven't had a chance to run it yet, because I'm getting married again next week and lots to do at the moment... (I must be insane)