Engine Revolutions Per Minute (RPM) can be "safe" at a variety of levels......depending entirely on what the vehicle is doing.
On the HIGH end:
If the question is meant to determine "how fast can my engine rev safely", the answer is, "Anything below the redline (preferably the orange line) drawn on the tachometer by the motorcycle manufacturer.
In the absence of a tach, you'll know by the screaming and wailing of your engine that you should be shifting gears.....NOW.
In these days of high fuel costs, lower RPM is better......notwithstanding the "Need for Speed"...and the desire to not blow up your engine.
On the LOW end:
If the question is meant to determine "how slowly can my engine rev safely", the answer is "As slow as it can without the engine chugging and lurching and possibly stalling....notwithstanding the possible need to accelerate quickly, which would of course require higher RPM.
It's an art and a science....with a little bit of politics thrown in on the side.
around 3000 rpm is a safe bet. It would help if you described the engine ( 4cyl / 6 cyl / 8 cyl.. 2700 - 3000 is safe....
the rpm of a c240 engine is 2000rpm
The highest safe RPM for a 5.8 liter Ford Bronco from 1993 is about 3,800. The engine will rev above that but it can cause damage.
Revolutions Per Minute ( RPM )
The operating range of rpm, for a C 12 Caterpillar diesel engine is 800 RPM to a maximum of 2400 RPM. The engine should be run at no more than 1800 RPM for a long period of time.
Depends on the engine that is turning 1,000 rpm's. A larger engine develops way more horsepower than a small engine at 1,000 rpm's.
Your engine is not running or your "RPM gauge" is broken.
Revolutions Per Minute ( RPM )
If you mean a 32% step up from the motor , it would 909.09 RPM
How to derive Engine RPM from revolution counter reading?
Max rpm / redline (often they are actually different) is not based on the car but on the engine. Prelude S (F22A1 engine) max rpm: 6250-ish Prelude VTEC (H22A engine) Redline: 7200/7600 rpm Max rpm: 7400/8000 rpm Preludes from 92- were delivered with the following engine options F20A, F22A, H23A, H22A.
A typical idle speed for a normal car engine is 600 rpm to 1,000 rpm. It is higher for buses and motorcycles. RPM stands for revolutions per minute.