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.

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.