Straight from the world launch in northern Spain, the 2020 EXC model range from KTM sees a whole host of exciting changes to catch the chassis and other things, up with the motocross models. The 450, 500 and 150 get the most action this time round with a special Erzberg model also featuring for 2020.

TPI ENGINE UPGRADES

For 2020, the cylinders are upgraded with fully machined exhaust port windows for improved timing precision. At the same time, a reworked exhaust control valve drive and adjuster produce more precise adjustment and increased efficiency.

A reworked idle system allows more precise idle speed setting via the bypass screw. An enhanced cold start system supplies an increased amount of extra air when opening the bypass.

Oil supplied by the electronically controlled oil pump via an oil intake tube is mixed with the incoming air to lubricate moving engine parts.

An updated version of the digital engine maps improves performance and power delivery of the 2020 TPI engines and works with new cylinder head and air-intakes.

A new and additional ambient air pressure sensor enables the ECU to adapt the injection parameters to fast changes in altitude.

The most exciting update for 2020 sees the popular 150 EXC score TPI, lining it up with the 250 and 300. Having had carburetor issues here in NZ for the last few years, the addition of TPI will change the game for the small-bore 2-stroke. It will also change its price too, increasing around $500 if we had to guess. Small price to pay for a bike that will run clean no matter the conditions.

4-Stroke Engine Updates

The new 250 4T engine features a new cylinder with a 78mm bore carried over from the successful KTM 250 SX-F motocross engine, which, in conjunction with a new cylinder head gasket, raises the compression ratio from 12.8:1 to 13.8:1.

The 350 EXC-F engine has a reworked cylinder head design, saving 200g. New, flow-optimized ports and two overhead camshafts are tuned for enduro specific torque characteristics.

The new head comes with a new cylinder head cover and gasket, a new spark plug and spark plug connector.

The 350’s short cylinder with a bore of 88mm features a reworked cooling system and houses a new, forged bridged box-type piston. Its piston crown geometry is matched to the high-compression combustion chamber with a compression ratio raised from 12.3 to 13.5 for increased power.

A reworked oil feed for MY2020 brings enhanced engine durability, with long crankshaft service intervals to save time, effort and cost.

Updated camshaft timings for improved performance, while a re-designed exhaust flange connects the header pipe more securely

450 & 500 Specific

The 2020 KTM 450 and 500 EXC-F engines are fitted with a new, more compact SOHC, 15mm lower and 500g lighter cylinder head.

Re-designed ports are controlled by a new overhead camshaft which is now closer to the centre of gravity to improve handling. An improved axial mount for the decompressor shaft means more reliable starting and a new, more efficient integrated engine breather system reduces oil losses.

New, 40mm titanium intake valves and 33mm steel exhaust valves are shorter and matched to the new head design. They are activated via rocker arms that have a more rigid design with reduced inertia, guaranteeing more consistent performance across the power range.

A shorter timing chain and new chain guides contribute to a reduction in weight and low friction, while a new spark plug increases combustion efficiency.

The short cylinder with a 95mm bore houses a new, lightweight box-in-box type piston made by König that, in conjunction with a 10% lighter piston pin, improves performance, lowers vibrations and engine speed strength. The compression ratio is also increased from 11.7:1 to 12.75:1.

FRAME

Connecting the cylinder head to the frame, the lateral engine headstays of all models are now made of aluminum, enhancing cornering precision while reducing vibrations KTM says.

Newly designed lateral frame guards feature a non-slip surface texture and the one on the right-hand side also provides heat protection against the silencer.

In the 250/300 EXC frames, the engine is rotated downwards by one degree around the swingarm pivot for improved front wheel traction.

The subframe is made of strong, especially lightweight profiles and now weighs less than 900g. To increase rear fender stability, it has been lengthened by 40mm.

EXHAUST

The 250 and 300cc models feature new heavy duty exhaust pipes made by KTM using an innovative 3D stamping process that makes it possible to provide the outer shells with a corrugated surface.

This renders the pipe a lot more rigid and resistant against rock and debris impacts, while significantly reducing noise KTM claims. At the same time, the exhaust pipes have an oval cross section for increased ground clearance and reduced width.

The 4-stroke models now feature two-piece header pipes for a more user-friendly dismantling, while providing better access to the shock absorber.

The two-stroke silencers with their new profile and new end cap have an increased volume as well as reworked internals developed individually for each model.

New perforated inner tubes and a new, lighter damping wool combine to provide more efficient noise damping and enhanced durability at approximately 200g less weight (on 250/300cc models).

A new, slightly wider aluminum sleeve and end cap result in more compact and shorter main silencers, bringing the weight closer to the center of gravity for increased mass centralization.

While the original XPLOR forks have come into some criticism, the PDS rear shock is great in the bush and when the gong gets tough. It will be interesting to see if the new forks are much better than 2019. Fingers crossed.

2020 KTM EXC Updates:

More efficient, high-performing two-stroke engines including a new ambient air pressure sensor enabling the ECU to adapt the injection parameters to air pressure
250/300 EXC 2T engines pivoted by one degree for improved front-end feel
New frame design for more torsional stiffness
Big capacity four stroke engines upgraded for power, efficiency and re-positioned centre of gravity
New, mid-valve piston in the WP forks to improve damping, plus new upper fork caps with new clicker adjusters
New bodywork and graphics including re-designed, 40mm longer rear subframe
New seat design
New air filter box
New shape fuel tanks
Reworked TPI oil tank with more flexible mountings for enhanced durability
Improved cooling system including 12mm lower radiators
four stroke engines no longer have kickstart or option to fit one as the mechanism is completely removed
All-new exhaust systems, notably the TPI expansion chambers for improved power, strength and reduced noise
Four stroke exhaust header pipes slimmer design because of removed kickstart provision
Fans as standard on 450 and 500 EXC-F models