The 2008 XB31-B 250 is an all new design replacing the Hummer 250-07. Using the same proven ZONGSHEN air-cooled four stroke engine, but with a vastly improved fully cradled seamless high strength steel chassis, no more separate bash plate for even greater strength. The rear swing arm has also been improved by increasing its length to accommodate the larger 18" rear wheel. Rear lower suspension points now use superior greaseable needle roller bearings coupled to a quality SHOWA rebound adjustable hydraulic shock that responds immediately to adjustment. Front suspension has also received a boost in the form of fully adjustable compression and rebound adjustable quality SHOWA USD forks that feel just fantastic. Improvements don't stop there, brakes have had an improvement in the form stainless steel braided hoses which offer, better brake feel. The front wheel is now 21" to fall in line with the 18" rear wheel making the XB31-B meet and equal international standards and get away from the 19"- 16" sizes frequently used on the Hummer models. Seat length has been increased providing a greater level of comfort. Drive chain is now a higher quality KMC brand offering better wear characteristics. The Air-Filter is a Australian made sponge, sports filter specially made for Zuma, this was required as the standard air filter is inadaquate.Turning circle has been improved 50% over the Hummer 250 making tight trail work a breeze. The XB31-B is now the best 250cc dirt bike in its class and are selling like hot cakes for under $2000, so get in and grab yourself the best there is complete with 3 months warranty and Zuma's garrenteed full spares back up.