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RS250 250cc Insert
56mm Insert for Cougar Head Billet Heads coloured Black, seals included.

For 250cc bikes only.


Volume Info:

Volumes as follows

Unleaded 250 version 11.1cc with 1.0mm squish

AVGAS 250 version 9.5cc with 0.8mm squish

All volumes include the plug hole. Roughly 1.9cc less for true volume, with the plug fitted.

If squish width is changed by 0.1mm, this would change volume for 250 insert by 0.25cc roughly, and for the 300 insert it would roughly be 0.3cc



Special clause for parts made by Cougar Red: These parts or kits are designed and manufactured for competition use and are sold "as-is without warranty". The entire risk as to performance and quality is with the with the buyer. It is a condition of our making these parts available that it is solely the decision of each individual, rider, team member or team whether they choose to use any parts supplied and in doing so this absolves The Tuning Works & Cougar Red of any claims including and not exclusively for; inconvenience, damage to equipment and/or injury to personnel irrespective of how caused. Parts are sold strictly for motorsport use. Use on road may violate local laws and parts are therefore fitted to road going vehicles entirely at the owners risk. If you wish to return this product for a refund you must notify TTW within 7 days of receipt and the parts must be in original unused condition. It is assumed when ordering or fitting these parts that you accept these terms.
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