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  • Based on the R2104 engine with improvements
  • Performance is improved by adopting a new mould of the crankcase
  • By changing the crankshaft, the counterweight from φ4 to φ4.5 and optimizing the weight balance, the feeling in the mid-low speed range is improved
  • Cylinder liner - adopts 9 ports that have a good reputation in R2104. The shape has been changed to match the new crankcase
  • Outerhead has been changed from conventional black colour to polished silver with clear coating
  • Cover plate - a well-established thrust plate, the same as that of B2104 is adopted

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    OS Engines Speed R2105 .21 On Road Engine Only, No Longer Available

    SKU: OSM1D900
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    The O.S. Speed R2105 Engine is a factory-tuned engine developed for 1/8 racing competitions. It is based on its predecessor, the R2104 engine, and has been further improved to have an easy-to-handle feeling that can be used on any course.

    $579.99
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    OS Engines Speed R2105 .21 On Road Engine Only, No Longer Available

    SKU: OSM1D900
    $579.99
    Loading...
    Loading...

    The O.S. Speed R2105 Engine is a factory-tuned engine developed for 1/8 racing competitions. It is based on its predecessor, the R2104 engine, and has been further improved to have an easy-to-handle feeling that can be used on any course.

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