I recently purchased a 1975 CB750K5 with 25k miles. Compression good at 150 across all four cylinders. Carbs were cleaned and there are no leaks. Runs strong. The mechanic that worked on it mentioned that due to its 33 year age, that I should not rev it to the 8,000 rpm redline; rather keep it below 6,000 rpm. Is there any reason other than age not to run it to the 8,000 rpm redline occasionally?
