TSP Yamaha YZ250 and YZ250X 1999-on Billet Head

Select your desired compression ratio from the drop down menu. All designs will work with stock base gaskets and cylinder heights and offer significant improvements over stock heads.

LOW COMPRESSION: This Low comp design is the same comp ratio as the stock 250X model head but with a much better design. It gives much better bottom/mid and much better part throttle response. It is the design we normally suggest for the X model at sea level.

MEDIUM COMPRESSION: This Med design is the same as we have been selling for the standard MX model for years. It is actually lower compression than stock but gives much better throttle response and smoother, crisper power delivery. It is suited the the standard YZ250 model at sea level and for high level MX where the engine is revved hard.

HIGH COMPRESSION: This new design is roughly the same compression ratio as the stock YZ250 head but with a much better design. It gives much more bottom/mid power than stock, plus higher peak power. It doesn’t rev out as far as the Medium design. It is best suited to trail-riding, off-road racing and MX where the rider wants max bottom/mid.

Our new TSP Billet cylinder heads are machined from solid 6061 T6 stock and offer improved performance, reliability and fuel economy. They are the best bolt on mod you can buy for your bike! Our design offers better heat dissipation than many other 2 piece designs due to the large lower section which incorporates the combustion chamber… this allows heat from combustion to disperse over a larger area than other 2 piece designs for improved heat transfer to the coolant.

These Billet machined 2 piece heads feature TSP’s proven combustion chamber designs and are a MUST HAVE mod for most current model offroad bikes. Our combustion chamber designs have been used by hundreds of happy customers and have been extensively dyno tested… the gains are consistent and include: increased power throughout the rev range (especially bottom/mid), improved fuel economy, greatly reduced risk of detonation, increased top end life in many models, and much SMOOTHER power delivery.

The unique Billet design has been 100% developed, machined and tested in-house at TSP.

These Billet heads will bolt onto your standard cylinder and are designed to work with standard base gaskets. If you are unsure of your current base gasket thickness we can advise the correct thickness to achieve the necessary cylinder height and squish clearance.

We can also advise baseline jetting specs to go with your new Billet head. The customer takes all responsibility for ensuring that jetting is appropriate for their riding style and conditions.

Below is this head in action on a YZ250, paired with our scalvini expansion chamber: