I'd save my money if it was me, the RT 180 is a playbike, and isn't really worth throwing more money into, as you'll never get it back. Save the money spent on upgrades, to put towards the purchase of a better bike that offers more performance instead.
It's a friends bike. I suggested he take the money to upgrade the forks, put it in a ziplock bag and duct tape it to the forks. Then the rear suspension, engine etc. When the bike is covered in duct tape, unwrap it and buy a new bike! :laugh: