Can a tire size change enable me to drop about 500 rpm?

[Davek80514]

I'm running about 3300 rpm in 5th gear at about 78-79 mph. Is there a tire I can safely change to that could drop that RPM under 3000

[Red Ron]

I am running a 195x60x16 and it dropped mine some but I can't remember how much. Next time out I will see what my rpm is at that speed.

[Davek80514]

I am running a 195x60x16 and it dropped mine some but I can't remember how much. Next time out I will see what my rpm is at that speed.

Thanks! If I'm careful on the twist on a long ride I can get 42mpg. I'm hoping by dropping under 3000rpm I can get better than that.

[Red Ron]

I am running a 195x60x16 and it dropped mine some but I can't remember how much. Next time out I will see what my rpm is at that speed.

Thanks! If I'm careful on the twist on a long ride I can get 42mpg. I'm hoping by dropping under 3000rpm I can get better than that.

Just got back from a ride. At the speed you mention (79 or 80) I am doing right at 3400 rpm even with my big tall 60 series. My speed was measured by gps. So if you are only doing 3300 at that speed you may want to stick with that tire. Mind you my tire has over 15k on it so that might make it a little less tall. But, it looks like it has another 15k left on it.

[mweddy@gmail.com]

I had a 180/70/16 tire on mine for a few thousand miles. There aren't a lot of choices in that size, but it does help a little. Not 500 RPM though. I could get 70 MPH at 3000 RPM. The bad part is that it was a Shinko, and it failed at around 6000 miles. It would be nice if there were more 70 series tires available. I am back to a stock 60 series tire, since I wanted to go back to a Bridgestone, and I don't think it was available in the 180/70/16.

[Dusty Boots]

I've run different sized tires (car and moto tires) on my 1500 that resulted in a 500 rpm drop between the shortest tire (175/60-16) and the tallest (175R-16) and there was no appreciable difference in gas mileage

Where there was a difference was in throttle response. With the taller tire, it was 'twist n wait' as throttle response was sluggish. With the smaller tire it was 'twist n GONE'!!!!

Because the wing is as aerodynamic as a barn door, once you get over 55 mph, the engine has to overcome these aerodynamic drag forces, which means using more power (ie fuel) to do so. The faster you go, the harder your engine has to work, burning more fuel!
You want better fuel economy? .... slow down!!

[702scottc]

42 mpg is quite respectable, how much more do you expect to get? A 500 rpm reduction isn't possible by simply replacing the rear tire. The engine was designed to run at those rpm' s with the recommended tire size. The performance would suffer especially when pulling your trailer and 2 up. Mine gets 40 mpg pretty consistently even running 80 plus mph. My 1500 would drop into the low 30's mpg running at those speeds. Take Dustys advice and slow down a bit to get better mileage,a few cents at the pump when filling up isn't worth the performance loss.

[Wingsconsin]

I've run different sized tires (car and moto tires) on my 1500 that resulted in a 500 rpm drop between the shortest tire (175/60-16) and the tallest (175R-16) and there was no appreciable difference in gas mileage

Where there was a difference was in throttle response. With the taller tire, it was 'twist n wait' as throttle response was sluggish. With the smaller tire it was 'twist n GONE'!!!!

Because the wing is as aerodynamic as a barn door, once you get over 55 mph, the engine has to overcome these aerodynamic drag forces, which means using more power (ie fuel) to do so. The faster you go, the harder your engine has to work, burning more fuel!
You want better fuel economy? .... slow down!!

TRUTH !

[Davek80514]

I'd like to say thanks to all of you for your opinions and suggestions. It's people just like all of you that make this the greatest country in the world, by being willing to share your knowledge, experiences & opinions to help others for no other reason but to be a helping hand to others. I'm thankful & proud to be a member here.

From myself & my family here in Colorado, I hope you & your families and have a safe & fun Independence day.
My God bless us all.
Dave K.

[DCTruncale]

www.tiresize.com has a ton of useful calculators for what happens to speed, rpm, etc. when you change tire sizes. Check it out!