For 2014 the host of engine changes witnessed for the 2013 model, which included a new connecting-rod material and design matched to a new piston, featuring ‘bridged box’ constrution with altered material densities in key areas giving less deflection at high rpm’s for greater performance and durability, matched to a revised DLC coated gudgeon pin, a new clutch basket with a friction reducing coating and new clutch plates, a new oil pump with modifcations to the oil galleries, revised ECU settings with mapping changes to suit the new engine characteristics and a new wiring loom, continue on to the 2014 model but with some alterations in key areas. After having another 12 months of testing at the highest levels of competition in the MX and Enduro World Championships the latest updates to the 250Fi engines come from development of the TM Factory Racing Teams. The 2014 engine will continue with the well proven 2013 alterations but now receive another new piston design (still box bridged) with an all new crown design, this allows for better burn control, power output and efficiency when combined with the new cylinder head shape with altered volumes. New EFI mapping settings for both ignition timing control and fuel injection control work in tune with the new head and piston arrangement to increase power and torque for a large part of the rev range, and these changes are different for both MX and Enduro variants too. Both the MX and Enduro engines have unique pistons and head profile variants to give the performance required for each discipline, on the MX engine a new inlet camshaft profile and a new larger diameter throttle body feature increase the performance values even further to suit the ‘harsher’ nature of Motocross, whilst the Enduro engine retains the smaller throttle body and ‘relaxed’ camshaft profiling to give a smother, broader power output better suited to the required conditions found in Enduro competition events. Other changes include new suspension settings with the new KYB fork fitted as standard, a new triple clamp design and a fresh new look featuring new decals and a new seat cover.
TM Racing ‘Factory’ rear shock absorber, Kayaba 48mm forks, billet machined aluminium hubs laced to anodised Excel rims, billet machined aluminium triple clamps with oversize taper handlebars, oversize ‘wave’ braking discs, switchable twin map ignition system, HGS ‘bomb’ exhaust system and a full lighting system EU compliant for road use.
Engine, single cylinder water cooled 4 stroke, twin camshafts driving 4 independent finger followers operating titanium valves, dry sump with twin rotor oil pump for recovery and distribution, Electronic fuel injection with 44mm throttle body, billet connecting rod with forged piston, electric starter with conventional kick.