Creating some of the lightest ‘ready to ride’ machines in their class has been a main-stay of TM Racing’s bikes. For 2018 TM promises a host of little changes, which add up to greater engine performance from all two-stroke models, improved handling from chassis changes and suspension revisions, combined with real ‘wet’ weight reductions and improved centralised mass.
The two-stroke bikes get the biggest amount of attention, though chassis changes to move the engine position slightly and changes to the way the frames are cast is common across all 2018 bikes.
The 125cc and 144cc two-strokes get plenty of attention for 2018. The engines get new cylinder configurations and port timing, along with new cylinder heads.
A new exhaust system plus new CDI programming and carburettor settings maximise performance alongside the TMEES electronically controlled exhaust valve.
Overall this gives better response with a gain in power and torque at the lower range, while strengthening the mid / top end performance.
The main focus of both the 250cc and 300cc engines for 2018 is the power delivery and performance. Both get a new gear position sensitive ignition, working alongside the TMEES exhaust valve with a new pulley arrangement and revised ECU programming.
Like the 125 and 144cc, the bigger two-strokes have revised cylinder ports and port timing, plus a new exhaust system for 2018 models to improve power output and delivery.
The 250 and 300 have optional ‘handlebar mounted’ twin ignition map switch means the power delivery for both models can be switched on track.
With the system adjusting itself depending on gear selection and valve position, the new developments work hard to get the best power delivery and traction at all times.
A 12-litre fuel tank on the two-stroke machines is an option for enduro models too. It does however reduce the intake size of the ‘Fresh Air’ system if fitted, so that option needs to be specified when you order your bike.
Four stroke changes
Changes to the 2018 four-stroke engines are minimal on the back of bigger changes in 2017 (including the successful 300 4T model), which included a stronger ‘box-bridge’ piston and a revised crown for higher compression ratios.
The 2018 four-stroke engines continue with the ‘reverse’ layout, which sees the fuel tank positioned under the seat, with air intake and filter above the engine. This allows the four-stroke engine to breathe cleaner air with a much more direct air feed into the Fi throttle body, improving performance.
Chassis changes to the 2018 models
Tailoring each chassis to model engine allows TM Racing to design and build each machine for minimal weight, compactness and better handling characteristics.
For 2018 overall weight is reduced across the enduro range with suspension revisions specific to each.
As mentioned, the engine position changes slightly on all 2018 models to tweak feel and performance, and there’s a change to the way frames are cast.
KYB 48mm twin chamber forks (50mm DLC coated Marzocchi on SMX models) get a friction reduction coating and have also been revised to improve response.
The TM Racing shock absorber, made in-house, adopts the latest ‘sealing’ system to reduce the frictional losses and increase shock performance.
This combined with 2017’s update to swing-arm length, linkage components and larger rear spindle diameter to limit flex, allows for a more progressive feel giving improved stability and traction.
The CNC machined billet aluminium wheels hubs, in anodized Excel rims, feature a new spoke arrangement for 2018.
A ‘tapering’ profile in a new stronger material treated to increase corrosion resistance, larger spoke nipples now feature on the front wheel also for added strength but reduced unsprung weight.
The ES abbreviation on any TM denotes ‘electric start’ and it’s powered by a new, lightweight, Lithium Ion battery that is recharged when the engine is running on all Fi Enduro models and Road models, but is also available as an option on Fi MX and SMX variants.