To do the mods cheap..... (see my review on my website
www.redbikejohn.com )
Decat exhaust and drill. .....free.
Buy kev's mods , fuel and co2. Co2 mod helped stalling on mine.
Filter ? Buy cheap.
Snorkel, remove. Make your own gasket from soil pipe gasket. Fiver.
Tyres, for road work I buy "full bore usa" tyres from my tyres in Germany. 60 for a rear but sometimes cheaper than that. Fine for commuting and road trips.